Prevent Bluetooth alerts from interrupting modal warnings

Prevent Bluetooth alerts from competing with sheets
Preserve open DMs across Bluetooth settings
2026-07-25 22:05:21 +00:00 · 2026-07-25 23:49:42 +02:00 · 2026-07-25 23:49:42 +02:00 · 2026-07-25 23:49:42 +02:00 · 2026-07-25 23:49:42 +02:00 · 2026-07-25 23:49:42 +02:00
381 changed files with 87839 additions and 11433 deletions
@@ -0,0 +1,30 @@
+name: Dead Code
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+jobs:
+  periphery:
+    name: Periphery scan
+    runs-on: macos-latest
+    timeout-minutes: 30
+    # Advisory, like SwiftLint (#1361): findings annotate the PR but don't
+    # block merges. Drop continue-on-error once the baseline proves stable.
+    continue-on-error: true
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v5
+
+      - name: Install Periphery
+        # homebrew-core formula; the peripheryapp tap lags years behind.
+        run: brew install periphery
+
+      - name: Scan for dead code
+        # Config comes from .periphery.yml; known findings (mostly iOS-only
+        # code invisible to a macOS scan) are suppressed by the committed
+        # baseline. --strict fails the step when NEW dead code appears.
+        run: periphery scan --strict --disable-update-check
@@ -131,10 +131,10 @@ jobs:
            echo "No coverage data found; skipping summary."
          fi

-  # SPM tests above only compile the macOS slice; this job covers the
-  # iOS-conditional code paths (UIKit, CoreBluetooth restoration, etc.).
+  # SPM tests do not link the shipping app targets. This job covers the
+  # iOS-conditional paths and both universal Release link configurations.
  ios-build:
-    name: Build iOS app (simulator)
+    name: Build Release apps (universal)
    runs-on: macos-latest
    timeout-minutes: 15

@@ -143,14 +143,29 @@ jobs:
        uses: actions/checkout@v5

      - name: Build iOS (simulator, no signing)
-        # arm64 only: the vendored arti.xcframework has no x86_64 simulator slice.
+        # Build both simulator architectures so CI validates every vendored
+        # Arti simulator slice and the configuration that ships.
        run: |
          set -o pipefail
          xcodebuild -project bitchat.xcodeproj \
            -scheme "bitchat (iOS)" \
+            -configuration Release \
            -sdk iphonesimulator \
            -destination 'generic/platform=iOS Simulator' \
-            ARCHS=arm64 \
+            ARCHS='arm64 x86_64' \
+            ONLY_ACTIVE_ARCH=NO \
+            CODE_SIGNING_ALLOWED=NO \
+            build
+
+      - name: Build macOS (universal, no signing)
+        run: |
+          set -o pipefail
+          xcodebuild -project bitchat.xcodeproj \
+            -scheme "bitchat (macOS)" \
+            -configuration Release \
+            -destination 'generic/platform=macOS' \
+            ARCHS='arm64 x86_64' \
+            ONLY_ACTIVE_ARCH=NO \
            CODE_SIGNING_ALLOWED=NO \
            build

@@ -0,0 +1 @@
+{"v1":{"usrs":["param-buf-arti_bootstrap_summary(_:_:)-s:3Tor22arti_bootstrap_summary33_954FD7701B4E47ABB5F166D1CF862DC9LLys5Int32VSpys4Int8VG_AEtF","param-dataDir-arti_start(_:_:)-s:3Tor10arti_start33_954FD7701B4E47ABB5F166D1CF862DC9LLys5Int32VSPys4Int8VG_s6UInt16VtF","param-len-arti_bootstrap_summary(_:_:)-s:3Tor22arti_bootstrap_summary33_954FD7701B4E47ABB5F166D1CF862DC9LLys5Int32VSpys4Int8VG_AEtF","param-socksPort-arti_start(_:_:)-s:3Tor10arti_start33_954FD7701B4E47ABB5F166D1CF862DC9LLys5Int32VSPys4Int8VG_s6UInt16VtF","s:13BitFoundation16PeerCapabilitiesV8wifiBulkACvpZ","s:13BitFoundation18KeychainReadResultO18isRecoverableErrorSbvp","s:13BitFoundation23KeychainManagerProtocolP11secureClearyySSzF","s:18bitchatTests_macOS12MockKeychainC11secureClearyySSzF","s:18bitchatTests_macOS20TrackingMockKeychainC11resetCountsyyF","s:18bitchatTests_macOS20TrackingMockKeychainC11secureClearyySSzF","s:18bitchatTests_macOS20TrackingMockKeychainC25totalSecureClearCallCountSivp","s:18bitchatTests_macOS20TrackingMockKeychainC26secureClearStringCallCountSivp","s:18bitchatTests_macOS20TrackingMockKeychainC27_secureClearStringCallCount06_AB6D1M24FD239F2969C82F4108818260LLSivp","s:18bitchatTests_macOS24FailingCacheSaveKeychain33_22380C7A11A569A0B83FA83F34C498A7LLC11secureClearyySSzF","s:18bitchatTests_macOS24MockGeohashPresenceTimer33_483587EFB96650EE130EFB09BBA2A1AALLC7handleryycvp","s:3Tor0A7ManagerC21goDormantOnBackgroundyyF","s:7bitchat10AppRuntimeC24handleScreenshotCaptured33_C8B369AD8BC1D9963A50CEDA77A4332ALLyyF","s:7bitchat10AppRuntimeC33handleDidBecomeActiveNotificationyyF","s:7bitchat10BLEServiceC18logBluetoothStatus33_69191C53E68500C17D98DBCF2BDA7100LLyySSF","s:7bitchat10BLEServiceC20centralRestorationID33_69191C53E68500C17D98DBCF2BDA7100LLSSvpZ","s:7bitchat10BLEServiceC22captureBluetoothStatus33_69191C53E68500C17D98DBCF2BDA7100LL7contextySS_tF","s:7bitchat10BLEServiceC23peripheralRestorationID33_69191C53E68500C17D98DBCF2BDA7100LLSSvpZ","s:7bitchat10BLEServiceC29scheduleBluetoothStatusSample33_69191C53E68500C17D98DBCF2BDA7100LL5after7contextySd_SStF","s:7bitchat10QRScanViewV8isActiveSbvp","s:7bitchat15BLEPeerRegistryV5countSivp","s:7bitchat15KeychainManagerC11secureClearyySSzF","s:7bitchat15PaymentChipViewV7openURL33_10AC50641B1EBCD52E5092A2E521D236LL7SwiftUI13OpenURLActionVvp","s:7bitchat15TransportConfigO29uiBatchDispatchStaggerSecondsSdvpZ","s:7bitchat15TransportConfigO35uiShareExtensionDismissDelaySecondsSdvpZ","s:7bitchat15TransportConfigO38bleBackgroundPendingConnectSlotReserveSivpZ","s:7bitchat17GossipSyncManagerC10persistNowyyF","s:7bitchat17NostrRelayManagerC15InboundEventKey33_E4160FE8A9A2C9D6308EAAD5A8B5CB07LLV7eventIDSSvp","s:7bitchat25LocationNotesDependenciesV3now10Foundation4DateVycvp","s:7bitchat25NWPathReachabilityMonitorC7monitor33_84633C9DBCAF57538179C1E04DB8E015LL7Network0bD0CSgvp"]}}
@@ -0,0 +1,21 @@
+# Periphery dead-code scan configuration (https://github.com/peripheryapp/periphery)
+#
+# CI runs the macOS scheme only (an iOS scan needs a device destination and
+# doubles the build time). macOS-only scans falsely flag iOS-only code —
+# state restoration, screenshot handlers, background BLE sampling — so those
+# findings live in .periphery.baseline.json rather than being "fixed".
+# When auditing by hand, scan BOTH schemes and intersect:
+#   periphery scan --schemes "bitchat (iOS)" -- -destination 'generic/platform=iOS' ARCHS=arm64
+project: bitchat.xcodeproj
+schemes:
+  - bitchat (macOS)
+retain_swift_ui_previews: true
+# Codable properties are (de)serialized via synthesized conformances the
+# indexer doesn't always attribute reads to: PrekeyBundleStore.StoredBundle
+# .noiseKey flaked CI as "assign-only" even while read in loadFromDisk —
+# and slipped past its baselined USR. Retaining Codable properties outright
+# is deterministic; a truly-dead Codable field is a persisted-format change
+# anyway, never a safe mechanical delete.
+retain_codable_properties: true
+relative_results: true
+baseline: .periphery.baseline.json
@@ -2,6 +2,7 @@
 # (CI checkouts are fresh, so this only matters in a working tree).
 excluded:
  - .build
+  - .claude
  - .swiftpm
  - .DerivedData
  - DerivedData
@@ -1,4 +1,4 @@
-MARKETING_VERSION = 1.5.4
+MARKETING_VERSION = 1.7.1
 CURRENT_PROJECT_VERSION = 1

 IPHONEOS_DEPLOYMENT_TARGET = 16.0
@@ -1,165 +1,155 @@
 # bitchat Privacy Policy

-*Last updated: June 2026*
+*Last updated: July 2026*

 ## Our Commitment

-bitchat is designed with privacy as its foundation. We believe private communication is a fundamental human right. This policy explains how bitchat protects your privacy.
+bitchat is designed for private, account-free communication. This policy describes what the app keeps on your device, what it sends when you use mesh or optional internet features, and how long local data can remain.

 ## Summary

- **No personal data collection** - We don't collect names, emails, or phone numbers
- **No accounts or company servers** - Mesh chat works peer-to-peer; optional Nostr features use public or user-selected relays
- **No tracking** - We have no analytics, telemetry, or user tracking
- **Open source** - You can verify these claims by reading our code
+- **No project-operated accounts or messaging servers** — Bluetooth mesh is peer-to-peer; optional internet features use public or user-selected Nostr relays.
+- **No analytics, advertising, telemetry, or tracking** — the app does not contain an analytics or advertising SDK.
+- **No sale of data** — the project does not sell user data or build advertising profiles.
+- **Open source** — the storage, networking, and cryptography described here can be inspected in the source code.

-## What Information bitchat Stores
+## What bitchat Stores on Your Device

-### On Your Device Only
+1. **Identity and cryptographic keys**
+   - Noise, signing, group, prekey, and optional Nostr identity material is generated locally.
+   - Secret keys are stored in the system keychain as device-only items. Public keys are shared when required for messaging, verification, groups, or Nostr events.
+   - Keys remain until they are rotated, removed by the relevant feature, or erased with panic wipe. Because operating-system keychains can outlive an uninstall, bitchat records a non-secret install marker and deletes surviving app keys before use after a later reinstall.

-1. **Identity Keys**
-   - Cryptographic private keys generated on first launch or when optional Nostr identities are created
-   - Stored locally in your device's secure storage
-   - Allows you to maintain "favorite" relationships across app restarts
-   - Private keys never leave your device; public keys are shared when needed for messaging
+2. **Nickname, preferences, and relationships**
+   - Your nickname, settings, favorites, petnames, read-receipt identifiers, and bounded operational metadata are stored locally.
+   - The share extension briefly places content you choose to share in the app-group preferences so the main app can import it.

-2. **Nickname**
-   - The display name you choose (or auto-generated)
-   - Stored only on your device
-   - Shared with peers you communicate with
+3. **Private group state**
+   - Group names, rosters, creator identity, and key epoch are stored as protected files in Application Support.
+   - Current group keys are stored in the keychain. Group state remains until you leave or remove the group, panic-wipe the app, or remove the app.

-3. **Message History** (if enabled)
-   - When room owners enable retention, messages are saved locally
-   - Stored encrypted on your device
-   - You can delete this at any time
+4. **Queued and carried private messages**
+   - An outgoing private message that has not been acknowledged may remain for up to 24 hours in a bounded, encrypted outbox. The outbox is sealed with ChaCha20-Poly1305 and its key is stored in the keychain.
+   - A device acting as a courier may store a bounded opaque end-to-end encrypted envelope for another user for up to 24 hours. The courier cannot read its message content.
+   - A panic wipe deletes both stores.

-4. **Favorite Peers**
-   - Public keys of peers you mark as favorites
-   - Stored only on your device
-   - Allows you to recognize these peers in future sessions
+5. **Recent public mesh messages and notices**
+   - Signed public mesh messages may be kept in a protected local gossip archive for up to 15 minutes so they can cross mesh partitions and survive a short relaunch.
+   - Public bulletin-board posts and deletion tombstones persist until the post's author-selected expiry, at most seven days. Both stores are bounded and panic-wipeable.
+   - These items are public to the mesh or board where they are posted; they are not confidential messages.

-5. **Optional Location Channel State**
-   - Your selected geohash channel, bookmarked geohashes, teleport flags, and bookmark display names
-   - Stored locally on your device so the location-channel UI can restore your choices
-   - Per-geohash Nostr identities are derived locally from a device seed stored in secure storage
-   - Exact latitude and longitude are not persisted by bitchat
+6. **Media attachments**
+   - Voice notes and images you send or receive can be stored under Application Support so they remain playable while referenced by the app.
+   - Incoming media is subject to a 100 MB quota with oldest-file eviction. Media is deleted by panic wipe or app removal; some outgoing media can otherwise remain on disk.

-### Temporary Session Data
+7. **Optional location-channel state**
+   - Your selected geohash channel, bookmarks, teleport flags, and bookmark display names are stored locally so the UI can restore them.
+   - Per-geohash Nostr identities are derived locally from a device seed stored in the keychain.
+   - bitchat does not persist exact latitude or longitude and does not include exact coordinates in mesh or Nostr messages.

-During each session, bitchat temporarily maintains:
- Active peer connections (forgotten when app closes)
- Routing information for message delivery
- Cached messages for offline peers (12 hours max)
- Your current location while optional location channels are enabled, used locally to compute geohash channels and friendly place names
+## Temporary Session Data

-## What Information is Shared
+While running, bitchat maintains active connections, routing state, deduplication state, and bounded in-memory conversation timelines. Closing the app clears the in-memory timelines and active connections, but it does not erase the persistent stores listed above.

-### With Other bitchat Users
+## What Is Shared

-When you use bitchat, nearby peers can see:
- Your chosen nickname
- Your ephemeral public key (changes each session)
- Messages you send to public rooms or directly to them
- Your approximate Bluetooth signal strength (for connection quality)
+### With Nearby Mesh Users

-### With Room Members
+Depending on the feature you use, nearby peers can receive:

-When you join a password-protected room:
- Your messages are visible to others with the password
- Your nickname appears in the member list
- Room owners can see you've joined
+- Your chosen nickname and public Noise/signing identity material.
+- Announce metadata such as supported capability flags and a bounded list of short direct-neighbor identifiers. When the bridge is enabled, an announce can also include its coarse rendezvous geohash cell.
+- Public mesh messages, public notices, and group-control packets you intentionally send.
+- Private ciphertext addressed to them, or opaque courier ciphertext they agree to carry.
+- Radio metadata available to the receiver, such as approximate Bluetooth signal strength.

-### With Nostr Relays (Optional Features)
+Noise identity keys can persist across sessions; do not treat them as anonymous identifiers. Panic wipe rotates local identity state.

-If you enable Nostr-backed features:
- Private fallback messages to mutual favorites are sent as encrypted NIP-17 gift wraps. Relays can see event metadata, but not message content.
- Public location-channel messages, location notes, and presence are scoped with geohash tags. Relays and other participants can see the geohash tag, event kind, timestamp, and public key used for that geohash.
- Exact GPS coordinates are not included in Nostr events by bitchat. The geohash precision you choose can still reveal an approximate area, from region-level to building-level.
- Automatic presence heartbeats are limited to low-precision geohashes (region, province, and city). More precise geohash posts happen only when you use those channels or location notes.
+### With Private Group Members

-## What We DON'T Do
+Private group members receive the group's name, roster, key epoch, and encrypted group traffic needed to participate. Group messages are confidential to devices holding the current group key, subject to the security of those devices and members.

-bitchat **never**:
- Collects personal information
- Sells or shares your exact GPS location
- Stores data on servers we operate
- Sells your data to advertisers or data brokers
- Uses analytics or telemetry
- Creates user profiles
- Requires registration
+### With Nostr Relays and Internet Gateways

-## Encryption
+Internet-backed features are optional. When enabled or used:

-All private messages use end-to-end encryption:
- **X25519** for key exchange
- **AES-256-GCM** for message encryption
- **Ed25519** for digital signatures
- **Argon2id** for password-protected rooms
+- Private fallback messages use BitChat's app-specific encrypted envelopes. This format is not NIP-17, NIP-44, or NIP-59 compatible. Relays can observe the recipient public-key tag, event timing and size, and network metadata, but not the message plaintext or stable sender identity.
+- Public location-channel messages, notes, notices, and presence include a geohash tag, event kind, timestamp, and a public key. A geohash reveals an approximate area; finer precision reveals a smaller area.
+- The optional mesh bridge publishes bridge-enabled public mesh messages and presence to a neighborhood rendezvous cell. Those messages are public to participants and relays for that cell. A per-message “nearby only” choice prevents that message from crossing the bridge.
+- Bridge courier drops contain opaque end-to-end encrypted envelopes and a rotating recipient tag. Relays still observe timing and network metadata.
+- A device with gateway features enabled may relay signed bridge/location traffic or opaque courier envelopes for nearby mesh devices.

-## Your Rights
+Nostr relays are operated by third parties. Their retention, logging, availability, and privacy practices are outside the project's control. Public events and encrypted events may remain on relays according to each relay's policy.

-You have complete control:
- **Delete Local State**: Triple-tap the logo to instantly wipe local keys, sessions, caches, and preferences
- **Leave Anytime**: Close the app and local presence stops; relay-backed presence ages out
- **No Account**: No account record exists for you to delete from us
- **Portability**: Your local state stays on your device unless you send messages, use optional relay-backed features, or export it
+## Location and Apple Services

-## Bluetooth & Permissions
+Location permission is optional and requested as when-in-use access. It is used to compute geohash channels, bridge rendezvous cells, and nearby place labels.

-bitchat requires Bluetooth permission to function:
- Used only for peer-to-peer communication
- Bluetooth is not used for tracking
- You can revoke this permission at any time in system settings
+- Exact coordinates are not included in bitchat mesh or Nostr payloads and are not persisted by bitchat.
+- A selected geohash can still reveal an approximate area to peers and relays.
+- When bitchat asks the operating system for a friendly place name, Apple's `CLGeocoder` service may process the location under Apple's privacy terms.
+- Revoking location permission stops live location sampling. Saved bookmarks remain until you remove them, panic-wipe the app, or remove the app.

-## Location Permission
+## Microphone, Camera, and Media Permissions

-Location permission is optional and is used only for location channels:
- Used to compute local geohash channels and display names
- Requested as when-in-use permission
- Exact coordinates are not shared in messages or stored by bitchat
- Selected and bookmarked geohashes may persist locally until you remove them, use panic wipe, or delete the app
- You can revoke this permission at any time in system settings
+- Microphone access is used only while you record a voice note or actively hold live push-to-talk. The resulting audio is sent to the mesh conversation you selected; public-conversation audio is public to that mesh, while private-conversation audio uses the private transport protections described below.
+- Voice-note and live-audio files can remain in Application Support under the media retention rules above.
+- Camera access is used to scan peer-verification QR codes. Photo-library access is used when you choose an image to send.
+- These permissions can be revoked in system settings. bitchat does not record microphone or camera input while the related capture UI is inactive.
+
+## Cryptography
+
+Private and public features use different protections:
+
+- Mesh private sessions use Noise XX with X25519, ChaCha20-Poly1305, and SHA-256.
+- Private group messages use ChaCha20-Poly1305; group state and relevant mesh packets use Ed25519 signatures.
+- Nostr events use secp256k1 Schnorr signatures. BitChat private envelopes use secp256k1 key agreement, HKDF-SHA256 with a BitChat-specific domain separator, and XChaCha20-Poly1305. The envelope format is proprietary, only interoperates with BitChat clients, and does not provide forward secrecy against later compromise of the recipient's static Nostr private key.
+- The persistent private-message outbox uses ChaCha20-Poly1305 with a key held in the keychain. Some other protected local identity state uses AES-GCM.
+- Public mesh, bridge, geohash, and board content is signed or authenticated as appropriate but is intentionally not confidential.
+
+No cryptographic system can protect content after a recipient reads, copies, screenshots, or exports it.
+
+## Data Retention Summary
+
+- **In-memory chat timelines and active connections:** until the app closes or state is cleared.
+- **Queued outgoing private messages:** until acknowledged, dropped by bounded policy, or 24 hours, whichever comes first.
+- **Opaque courier envelopes:** until handed off, evicted by bounded policy, or 24 hours, whichever comes first.
+- **Recent public mesh gossip:** up to 15 minutes.
+- **Public board posts and tombstones:** until expiry, at most seven days.
+- **Groups, favorites, preferences, identity keys, bookmarks, and media:** until removed by the feature, panic wipe, quota eviction where applicable, or app removal.
+- **Nostr data:** according to the policies of the relays that receive it.
+
+## Your Controls
+
+- **Panic wipe:** Triple-tap the logo to synchronously cancel in-flight media work and clear local keys, sessions, preferences, groups, queues, carried mail, public archives, board data, and media managed by the app.
+- **Feature controls:** Location channels, mesh bridge, internet gateway, and related internet behaviors can be disabled in the app. Some already-published relay data cannot be recalled.
+- **System permissions:** Bluetooth, location, microphone, camera, and photo-library access can be revoked in system settings.
+- **No account:** The project operates no account record for you to request or export.
+
+## What the Project Does Not Do
+
+bitchat does not:
+
+- Operate an account database or project-owned messaging backend.
+- Include advertising, analytics, or tracking SDKs.
+- Sell user data or create advertising profiles.
+- Include exact GPS coordinates in bitchat mesh or Nostr message payloads.

 ## Children's Privacy

-bitchat does not knowingly collect information from children. The app has no age verification because it collects no personal information from anyone.
-
-## Data Retention
-
- **Messages**: Deleted from memory when app closes (unless room retention is enabled)
- **Identity Key**: Persists until you delete the app
- **Favorites**: Persist until you remove them or delete the app
- **Location channel choices**: Selected/bookmarked geohashes persist locally until removed, panic-wiped, or the app is deleted
- **Nostr relay data**: Public geohash events and encrypted gift wraps may be retained by relays according to each relay's policy
- **Everything Else**: Exists only during active sessions
-
-## Security Measures
-
- All communication is encrypted
- No accounts or company servers
- Optional Nostr relays receive only the events needed for Nostr-backed private fallback or public location channels
- Open source code for public audit
- Regular security updates
- Cryptographic signatures prevent tampering
+The project does not knowingly operate a service that collects children's personal data. The app has no account registration or age-verification system. Users and guardians should understand that public mesh, board, bridge, and location-channel posts are visible to other participants and may be relayed.

 ## Changes to This Policy

-If we update this policy:
- The "Last updated" date will change
- The updated policy will be included in the app
- No retroactive changes can make us collect data already held only in your app
+Material behavior changes will be reflected in this document and its “Last updated” date. Updating this policy cannot retroactively retrieve data that remained only on a user's device.

 ## Contact

 bitchat is an open source project. For privacy questions:
- View our source code: [https://github.com/permissionlesstech/bitchat/tree/main](https://github.com/permissionlesstech/bitchat/tree/main)
- Open an issue on GitHub
- Join the discussion in public rooms

-## Philosophy
-
-Privacy isn't just a feature—it's the entire point. bitchat proves that modern communication doesn't require surrendering your privacy. No accounts, no company servers, no analytics. Just people talking freely.
+- View the source: [https://github.com/permissionlesstech/bitchat](https://github.com/permissionlesstech/bitchat)
+- Open an issue on GitHub.

 ---

-*This policy is released into the public domain under The Unlicense, just like bitchat itself.*
+*This policy is released into the public domain under The Unlicense, like the project itself.*
@@ -63,7 +63,11 @@ let package = Package(
                // Only the vector fixture: declaring the whole "Noise"
                // directory would claim its .swift test files as resources
                // and silently drop them from compilation.
-                .process("Noise/NoiseTestVectors.json")
+                .process("Noise/NoiseTestVectors.json"),
+                // Frozen output produced by the released 733098bb private-DM
+                // implementation; proves receive compatibility independently
+                // of the refactored legacy generator.
+                .process("Nostr/Fixtures")
            ]
        )
    ]
@@ -19,7 +19,7 @@ This project is released into the public domain. See the [LICENSE](LICENSE) file
 - **Intelligent Message Routing**: Automatically chooses best transport (Bluetooth → Nostr fallback)
 - **Decentralized Mesh Network**: Automatic peer discovery and multi-hop message relay over Bluetooth LE
 - **Privacy First**: No accounts, no phone numbers, no persistent identifiers
- **Private Message End-to-End Encryption**: [Noise Protocol](https://noiseprotocol.org) for mesh, NIP-17 for Nostr
+- **Private Message End-to-End Encryption**: [Noise Protocol](https://noiseprotocol.org) for mesh, BitChat private envelopes for Nostr fallback
 - **IRC-Style Commands**: Familiar `/slap`, `/msg`, `/who` style interface
 - **Universal App**: Native support for iOS and macOS
 - **Emergency Wipe**: Triple-tap to instantly clear all data
@@ -44,9 +44,50 @@ BitChat uses a **hybrid messaging architecture** with two complementary transpor
 - **Global Reach**: Connect with users worldwide via internet relays
 - **Location Channels**: Geographic chat rooms using geohash coordinates
 - **290+ Relay Network**: Distributed across the globe for reliability
- **NIP-17 Encryption**: Gift-wrapped private messages for internet privacy
+- **BitChat Private Envelopes**: App-specific encrypted private messages over Nostr relays
 - **Ephemeral Keys**: Fresh cryptographic identity per geohash area

+BitChat's private-envelope format is proprietary and is **not** NIP-17,
+NIP-44, or NIP-59 compatible. It uses Nostr as a relay transport but only
+interoperates with BitChat clients. New envelopes use provisional,
+BitChat-specific public kind 1402 (not a formally reserved Nostr kind),
+encrypted inner kinds 1403/1404, and the `bitchat-pm-v1:` content prefix.
+For mixed-version delivery, clients publish both the primary kind-1402
+envelope and a compatibility kind-1059 copy. There is no date-based cutoff:
+kind 1059 must remain enabled until a coordinated iOS/Android release confirms
+that supported older clients have migrated. Receivers subscribe to both kinds
+and deduplicate the authenticated embedded BitChat payload.
+
+Private-envelope migration compatibility:
+
+| Sender | Receiver | Delivery path |
+| --- | --- | --- |
+| New iOS | New iOS | Kind 1402 is primary; the kind-1059 twin is deduplicated |
+| New iOS | Released iOS | Compatibility kind 1059 |
+| New iOS | Current Android | Compatibility kind 1059 |
+| Released iOS | New iOS | Kind 1059 with the released empty inner-tag shape |
+| Current Android | New iOS | Kind 1059 with exactly the authenticated recipient `p` tag |
+
+New kind-1402 envelopes require an empty inner tag list. The Android recipient
+tag exception is intentionally confined to legacy kind 1059 and accepts only
+the exact addressed recipient. Mailbox subscriptions cover the 24-hour
+delivery window plus Android's full 48-hour timestamp randomization and 15
+minutes of clock skew. Recovery uses
+one independent 500-event relay filter per wire kind so either format cannot
+consume the other's result budget.
+
+The two outbound migration copies are admitted to the relay queue as one
+protected batch. Queue pressure evicts ephemeral traffic first, never one copy
+of a private pair; if protected capacity is exhausted, the entire new pair is
+rejected as a whole. User-message rejection becomes a visible failed delivery;
+acknowledgements and favorite notifications retain the exact pair in a
+process-wide 256-entry bounded retry queue. A sustained outage beyond that
+bound evicts the oldest whole control pair with an explicit warning, never half
+a pair.
+If either socket write fails, the same queued pair remains pending and both
+copies are replayed on the replacement connection. A terminal relay target is
+pruned after bounded retries so one dead relay cannot wedge healthy delivery.
+
 ### Channel Types

 #### `mesh #bluetooth`
@@ -80,7 +121,7 @@ Private messages use **intelligent transport selection**:
 2. **Nostr Fallback** (when Bluetooth unavailable)

   - Uses recipient's Nostr public key
-   - NIP-17 gift-wrapping for privacy
+   - BitChat's app-specific private-envelope encryption
   - Routes through global relay network

 3. **Smart Queuing** (when neither available)
@@ -25,7 +25,7 @@ bitchat is a decentralized, peer-to-peer messaging application for secure, priva
 Two transports implement a common `Transport` interface and are coordinated by a `MessageRouter`:

 * **BLE mesh** — every device is simultaneously a GATT central and peripheral, relaying packets in a controlled flood. No infrastructure, pairing, or accounts.
-* **Nostr** — private messages to mutual favorites travel as NIP-17 gift-wrapped events over public relays (over Tor where enabled), bridging separate meshes through the internet.
+* **Nostr** — private messages to mutual favorites travel in BitChat's app-specific encrypted envelopes over public relays (over Tor where enabled), bridging separate meshes through the internet.

 The router prefers a live mesh link, falls back to Nostr, and engages the courier system when neither can deliver promptly.

@@ -78,7 +78,9 @@ Courier envelopes are sealed to the recipient's *static* key with the one-way No

 ### 5.3 Nostr Path

-Private messages to mutual favorites are wrapped per NIP-17/NIP-59: a rumor (kind 14) sealed (kind 13) and gift-wrapped (kind 1059) under a throwaway ephemeral key, so relays learn neither sender nor content.
+Private messages to mutual favorites use BitChat's proprietary private-envelope protocol. An unsigned inner message (kind 1404) is encrypted and placed in a sender-signed seal (kind 1403); that seal is encrypted again inside a public envelope (kind 1402) signed by a one-time key. Kind 1402 is a provisional BitChat-specific assignment, not a formally reserved Nostr kind. Each encrypted content field is `bitchat-pm-v1:` followed by base64url of a 24-byte nonce, XChaCha20-Poly1305 ciphertext, and its 16-byte tag. Keys come from secp256k1 ECDH and HKDF-SHA256 with a BitChat-specific domain separator.
+
+This format is **not NIP-17, NIP-44, or NIP-59 compatible** and interoperates only with BitChat clients. The outer `p` tag exposes the recipient's Nostr public key to relays; the stable sender identity and plaintext remain inside authenticated ciphertext. New-format seal and envelope timestamps are randomized up to 15 minutes into the past, while the actual message timestamp is encrypted. Legacy Android envelopes can carry public-layer timestamps randomized across the preceding 48 hours. The protocol does not provide forward secrecy: compromise of the recipient's static Nostr private key can expose stored envelopes.

 ## 6. Store and Forward

@@ -105,7 +107,11 @@ Public broadcast messages are cached (1000 packets) and reconciled between peers

 ### 6.4 Nostr Mailboxes

-Gift-wrapped messages rest on Nostr relays; clients re-subscribe with a 24-hour lookback on reconnect, covering the both-devices-offline case for mutual favorites whenever either side touches the internet.
+BitChat private envelopes rest on Nostr relays; clients re-subscribe across the 24-hour delivery window plus the full 48-hour timestamp randomization used by deployed Android clients and 15 minutes of clock skew (72 hours 15 minutes total). During the rolling format migration, clients subscribe to both the provisional BitChat-specific kind 1402 and historical kind 1059. Recovery places the kinds in separate filters within one REQ, each with an independent 500-event limit, so traffic in one format cannot starve the other. Each logical payload is published first in the primary kind-1402 format and then as a compatibility legacy copy for older iOS and current Android clients. There is no calendar cutoff: legacy publication and reception remain until a coordinated cross-platform release confirms supported clients have migrated. Bounded dedup of the authenticated embedded payload collapses the migration pair at receivers.
+
+The relay send queue treats those two events as one protected batch. Capacity pressure removes ephemeral events before regular traffic and never evicts only one private-envelope copy. A queue containing only protected batches rejects a new pair as a whole: user messages surface a failed delivery, while acknowledgements and favorite notifications retain the exact pair in one process-wide 256-entry bounded-backoff retry queue shared by account and short-lived geohash transports. Sustained control-payload overflow evicts the oldest whole pair with an explicit warning rather than growing memory or splitting formats. After either socket write fails, the same pair remains pending and both copies are replayed on the replacement connection. Terminal relay targets are pruned after bounded connection retries; a batch that succeeded elsewhere retires normally, while an all-target failure returns to the transport's failure/retry policy. Receive-side dedup suppresses the replay if one copy had already reached the relay.
+
+Released iOS legacy envelopes use an empty inner tag list. Current Android legacy envelopes use exactly one inner `p` tag naming the recipient. The kind-1059 decoder accepts only those two shapes after authenticating the outer recipient and sender-signed seal; alternate recipients, duplicate tags, and extra tags are rejected. Kind 1402 remains strict and permits no inner tags.

 ### 6.5 Delivery Metrics

@@ -127,7 +133,7 @@ Bare local counters (deposits, handovers, sprays, opens, outbox flushes and drop
 * **Flooding abuse** is bounded by TTL clamps, deduplication, per-depositor quotas, connect-rate limits, and announce-rate limiting.
 * **Replay** of public broadcasts is bounded by the 6-hour acceptance window plus deduplication; private payloads are protected by Noise nonces.
 * **Metadata.** BLE proximity is inherently observable; ephemeral IDs and daily-rotating courier tags limit long-term correlation. Nostr traffic can ride Tor.
-* **No forward secrecy for sealed mail** (§5.2) is the main cryptographic trade-off of the offline path.
+* **No forward secrecy for sealed mail or Nostr envelopes** (§5.2–5.3) means compromise of a recipient's static key can expose retained ciphertext addressed to that key.

 ## 9. Future Work

@@ -92,7 +92,8 @@
 		A6E32D232E762EAB0032EA8A /* Exceptions for "bitchatShareExtension" folder in "bitchatShareExtension" target */ = {
 			isa = PBXFileSystemSynchronizedBuildFileExceptionSet;
 			membershipExceptions = (
-				ShareViewController.swift,
+				Info.plist,
+				bitchatShareExtension.entitlements,
 			);
 			target = 57CA17A36A2532A6CFF367BB /* bitchatShareExtension */;
 		};
@@ -258,9 +259,13 @@
 			buildConfigurationList = E4EA6DC648DF55FF84032EB5 /* Build configuration list for PBXNativeTarget "bitchatShareExtension" */;
 			buildPhases = (
 				0A08E70F08F55FD5BA8C7EF3 /* Sources */,
+				7E9B64F63F93443FB7BA12DF /* Resources */,
 			);
 			buildRules = (
 			);
+			fileSystemSynchronizedGroups = (
+				A6E32D212E762EAB0032EA8A /* bitchatShareExtension */,
+			);
 			name = bitchatShareExtension;
 			productName = bitchatShareExtension;
 			productReference = 61F92EBA29C47C0FCC482F1F /* bitchatShareExtension.appex */;
@@ -332,6 +337,7 @@
 				es,
 				ar,
 				de,
+				fa,
 				fr,
 				he,
 				id,
@@ -388,6 +394,13 @@
 				E0A1B2C3D4E5F6012345678E /* relays/online_relays_gps.csv in Resources */,
 			);
 		};
+		7E9B64F63F93443FB7BA12DF /* Resources */ = {
+			isa = PBXResourcesBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
 /* End PBXResourcesBuildPhase section */

 /* Begin PBXSourcesBuildPhase section */
@@ -36,34 +36,12 @@ enum AppEvent: Sendable, Equatable {
 actor AppEventStream {
    private var continuations: [UUID: AsyncStream<AppEvent>.Continuation] = [:]

-    func stream() -> AsyncStream<AppEvent> {
-        let id = UUID()
-        return AsyncStream { continuation in
-            continuations[id] = continuation
-            continuation.onTermination = { [id] _ in
-                Task {
-                    await self.removeContinuation(id)
-                }
-            }
-        }
-    }
-
    func emit(_ event: AppEvent) {
        for continuation in continuations.values {
            continuation.yield(event)
        }
    }

-    func finish() {
-        for continuation in continuations.values {
-            continuation.finish()
-        }
-        continuations.removeAll()
-    }
-
-    private func removeContinuation(_ id: UUID) {
-        continuations.removeValue(forKey: id)
-    }
 }

 /// Identity key for a direct conversation. Equality and hashing use the
@@ -10,6 +10,10 @@ final class AppChromeModel: ObservableObject {
    @Published var showingFingerprintFor: PeerID?
    @Published var isAppInfoPresented = false
    @Published var isLocationChannelsSheetPresented = false
+    @Published var isNoticesSheetPresented = false
+    /// When the sheet is opened for "notes left here" (empty mesh timeline),
+    /// it should land on the geo tab instead of the channel-derived default.
+    @Published var noticesSheetPrefersGeoTab = false
    @Published var showBluetoothAlert = false
    @Published var bluetoothAlertMessage = ""
    @Published var bluetoothState: CBManagerState = .unknown
@@ -17,6 +21,9 @@ final class AppChromeModel: ObservableObject {

    private let chatViewModel: ChatViewModel
    private var cancellables = Set<AnyCancellable>()
+    /// The composer owns capture state above ChatViewModel. ContentView
+    /// installs this hook so both panic entry points synchronously stop it.
+    private var prepareForPanic: (@MainActor () -> Void)?

    /// Bulletin-board coordinator, created on first use of the board sheet.
    private(set) lazy var boardManager = BoardManager(transport: chatViewModel.meshService)
@@ -62,6 +69,11 @@ final class AppChromeModel: ObservableObject {
        isAppInfoPresented = true
    }

+    func presentNotices(geoTab: Bool = false) {
+        noticesSheetPrefersGeoTab = geoTab
+        isNoticesSheetPresented = true
+    }
+
    /// Builds the mesh topology map model from the transport's gossiped
    /// graph plus the live nickname table. Unknown nodes (heard about via a
    /// neighbor claim but never announced to us) fall back to a short ID.
@@ -88,7 +100,12 @@ final class AppChromeModel: ObservableObject {
        showScreenshotPrivacyWarning = true
    }

+    func setPanicPreparation(_ preparation: (@MainActor () -> Void)?) {
+        prepareForPanic = preparation
+    }
+
    func panicClearAllData() {
+        prepareForPanic?()
        chatViewModel.panicClearAllData()
    }

@@ -18,8 +18,6 @@ final class AppRuntime: ObservableObject {
    /// (docs/CONVERSATION-STORE-DESIGN.md). Owned here; the feature models
    /// and `ChatViewModel` observe and mutate it through its intent API.
    let conversations: ConversationStore
-    let peerIdentityStore: PeerIdentityStore
-    let locationPresenceStore: LocationPresenceStore
    let publicChatModel: PublicChatModel
    let privateInboxModel: PrivateInboxModel
    let privateConversationModel: PrivateConversationModel
@@ -28,6 +26,7 @@ final class AppRuntime: ObservableObject {
    let locationChannelsModel: LocationChannelsModel
    let peerListModel: PeerListModel
    let appChromeModel: AppChromeModel
+    let boardAlertsModel: BoardAlertsModel

    private let idBridge: NostrIdentityBridge
    private var cancellables = Set<AnyCancellable>()
@@ -41,7 +40,7 @@ final class AppRuntime: ObservableObject {
    #endif

    init(
-        keychain: KeychainManagerProtocol = KeychainManager(),
+        keychain: KeychainManagerProtocol = KeychainManager.makeDefault(),
        idBridge: NostrIdentityBridge = NostrIdentityBridge()
    ) {
        self.idBridge = idBridge
@@ -50,8 +49,6 @@ final class AppRuntime: ObservableObject {
        let locationPresenceStore = LocationPresenceStore()
        let locationManager = LocationChannelManager.shared
        self.conversations = conversations
-        self.peerIdentityStore = peerIdentityStore
-        self.locationPresenceStore = locationPresenceStore
        self.chatViewModel = ChatViewModel(
            keychain: keychain,
            idBridge: idBridge,
@@ -91,13 +88,34 @@ final class AppRuntime: ObservableObject {
            chatViewModel: self.chatViewModel,
            privateInboxModel: self.privateInboxModel
        )
+        let chatViewModel = self.chatViewModel
+        self.boardAlertsModel = BoardAlertsModel(
+            arrivals: BoardStore.shared.postArrivals.eraseToAnyPublisher(),
+            wipes: BoardStore.shared.didWipe.eraseToAnyPublisher(),
+            dependencies: BoardAlertsModel.Dependencies(
+                isOwnPost: { post in
+                    let key = chatViewModel.meshService.noiseSigningPublicKeyData()
+                    return !key.isEmpty && key == post.authorSigningKey
+                },
+                emitSystemLine: { content, geohash in
+                    if geohash.isEmpty {
+                        chatViewModel.addMeshOnlySystemMessage(content)
+                    } else {
+                        chatViewModel.addGeohashSystemMessage(content, geohash: geohash)
+                    }
+                }
+            )
+        )

+        if chatViewModel.networkActivationAllowed {
            GeoRelayDirectory.shared.prefetchIfNeeded()
+        }
        bindRuntimeObservers()
        NotificationDelegate.shared.runtime = self
    }

    func start() {
+        guard chatViewModel.networkActivationAllowed else { return }
        guard !started else {
            checkForSharedContent()
            return
@@ -136,12 +154,14 @@ final class AppRuntime: ObservableObject {
    }

    func handleDidBecomeActiveNotification() {
+        guard chatViewModel.networkActivationAllowed else { return }
        chatViewModel.handleDidBecomeActive()
        checkForSharedContent()
    }

    #if os(macOS)
    func handleMacDidBecomeActiveNotification() {
+        guard chatViewModel.networkActivationAllowed else { return }
        record(.scenePhaseChanged(.active))
        chatViewModel.handleDidBecomeActive()
        checkForSharedContent()
@@ -160,6 +180,7 @@ final class AppRuntime: ObservableObject {
            didEnterBackground = true

        case .active:
+            guard chatViewModel.networkActivationAllowed else { return }
            record(.scenePhaseChanged(.active))
            chatViewModel.meshService.startServices()
            TorManager.shared.setAppForeground(true)
@@ -202,7 +223,17 @@ final class AppRuntime: ObservableObject {
        chatViewModel.applicationWillTerminate()
    }

-    func handleNotificationResponse(identifier: String, userInfo: [AnyHashable: Any]) {
+    func handleNotificationResponse(
+        identifier: String,
+        actionIdentifier: String = UNNotificationDefaultActionIdentifier,
+        userInfo: [AnyHashable: Any]
+    ) {
+        guard chatViewModel.networkActivationAllowed else { return }
+        if actionIdentifier == NotificationService.waveActionID {
+            chatViewModel.sendMeshWave()
+            return
+        }
+
        if identifier.hasPrefix("private-"), let peerID = PeerID(str: userInfo["peerID"] as? String) {
            record(.notificationOpened(peerID: peerID))
            chatViewModel.startPrivateChat(with: peerID)
@@ -249,6 +280,8 @@ private extension AppRuntime {
        NotificationCenter.default.publisher(for: .TorWillRestart)
            .receive(on: DispatchQueue.main)
            .sink { [weak self] _ in
+                guard self?.chatViewModel.networkActivationAllowed == true
+                else { return }
                self?.record(.torLifecycleChanged(.willRestart))
                self?.chatViewModel.handleTorWillRestart()
            }
@@ -257,6 +290,8 @@ private extension AppRuntime {
        NotificationCenter.default.publisher(for: .TorDidBecomeReady)
            .receive(on: DispatchQueue.main)
            .sink { [weak self] _ in
+                guard self?.chatViewModel.networkActivationAllowed == true
+                else { return }
                self?.record(.torLifecycleChanged(.didBecomeReady))
                self?.chatViewModel.handleTorDidBecomeReady()
            }
@@ -265,6 +300,8 @@ private extension AppRuntime {
        NotificationCenter.default.publisher(for: .TorWillStart)
            .receive(on: DispatchQueue.main)
            .sink { [weak self] _ in
+                guard self?.chatViewModel.networkActivationAllowed == true
+                else { return }
                self?.record(.torLifecycleChanged(.willStart))
                self?.chatViewModel.handleTorWillStart()
            }
@@ -273,6 +310,8 @@ private extension AppRuntime {
        NotificationCenter.default.publisher(for: .TorUserPreferenceChanged)
            .receive(on: DispatchQueue.main)
            .sink { [weak self] notification in
+                guard self?.chatViewModel.networkActivationAllowed == true
+                else { return }
                self?.record(.torLifecycleChanged(.preferenceChanged))
                self?.chatViewModel.handleTorPreferenceChanged(notification)
            }
@@ -289,21 +328,30 @@ private extension AppRuntime {
    }

    func checkForSharedContent() {
-        guard let userDefaults = UserDefaults(suiteName: BitchatApp.groupID),
-              let sharedContent = userDefaults.string(forKey: "sharedContent"),
+        guard chatViewModel.networkActivationAllowed else { return }
+        guard let userDefaults = UserDefaults(suiteName: BitchatApp.groupID) else { return }
+        let clearSharedContent = {
+            userDefaults.removeObject(forKey: "sharedContent")
+            userDefaults.removeObject(forKey: "sharedContentType")
+            userDefaults.removeObject(forKey: "sharedContentDate")
+        }
+
+        guard let sharedContent = userDefaults.string(forKey: "sharedContent"),
              let sharedDate = userDefaults.object(forKey: "sharedContentDate") as? Date else {
+            // A partial or malformed handoff must not linger in the shared
+            // app-group container indefinitely.
+            clearSharedContent()
            return
        }

        guard Date().timeIntervalSince(sharedDate) < TransportConfig.uiShareAcceptWindowSeconds else {
+            clearSharedContent()
            return
        }

        let contentKind = SharedContentKind(rawValue: userDefaults.string(forKey: "sharedContentType") ?? "") ?? .text

-        userDefaults.removeObject(forKey: "sharedContent")
-        userDefaults.removeObject(forKey: "sharedContentType")
-        userDefaults.removeObject(forKey: "sharedContentDate")
+        clearSharedContent()

        switch contentKind {
        case .url:
@@ -327,7 +375,9 @@ private extension AppRuntime {
        let becameConnected = isConnected && !lastNostrRelayConnectedState
        lastNostrRelayConnectedState = isConnected

-        guard started, becameConnected else { return }
+        guard chatViewModel.networkActivationAllowed,
+              started,
+              becameConnected else { return }

        let isInitialConnection = !didHandleInitialNostrConnection
        didHandleInitialNostrConnection = true
@@ -349,12 +399,12 @@ private extension AppRuntime {
            TorManager.shared.isAutoStartAllowed() {
            chatViewModel.torStatusAnnounced = true
            chatViewModel.addGeohashOnlySystemMessage(
-                String(localized: "system.tor.starting", defaultValue: "starting tor...", comment: "System message when Tor is starting")
+                String(localized: "system.tor.starting", comment: "System message when Tor is starting")
            )
        } else if !TorManager.shared.torEnforced && !chatViewModel.torStatusAnnounced {
            chatViewModel.torStatusAnnounced = true
            chatViewModel.addGeohashOnlySystemMessage(
-                String(localized: "system.tor.dev_bypass", defaultValue: "development build: Tor bypass enabled.", comment: "System message when Tor bypass is enabled in development")
+                String(localized: "system.tor.dev_bypass", comment: "System message when Tor bypass is enabled in development")
            )
        }
    }
@@ -225,8 +225,25 @@ final class Conversation: ObservableObject, Identifiable {
        guard let current else { return false }
        if current == new { return true }

+        // Never downgrade to a weaker delivery state. Ordering of certainty:
+        // sending < sent < carried < delivered < read. A late `.sent` write
+        // (e.g. the optimistic stamp after routing) must not clobber the
+        // `.carried` the router already set when it handed a copy to a
+        // courier/bridge, nor a `.delivered`/`.read` ack. A late asynchronous
+        // failure is weaker than a confirmed recipient receipt too, so it may
+        // not replace `.delivered`/`.read`. Same for the
+        // `.sending` stamp a pre-handshake resend emits asynchronously: it
+        // can land after the message already reached `.sent`, and "Sent" was
+        // already truthful. (`.failed` → `.sending` stays allowed so a real
+        // failure retry is visible.)
        switch (current, new) {
-        case (.read, .delivered), (.read, .sent):
+        case (.read, .delivered), (.read, .carried), (.read, .sent), (.read, .sending), (.read, .failed):
+            return true
+        case (.delivered, .carried), (.delivered, .sent), (.delivered, .sending), (.delivered, .failed):
+            return true
+        case (.carried, .sent), (.carried, .sending):
+            return true
+        case (.sent, .sending):
            return true
        default:
            return false
@@ -796,16 +813,6 @@ extension ConversationStore {
        return messageIDs
    }

-    /// Removes every direct conversation (panic clear).
-    func removeAllDirectConversations() {
-        let directIDs = conversationIDs.filter { id in
-            if case .direct = id { return true }
-            return false
-        }
-        for id in directIDs {
-            removeConversation(id)
-        }
-    }
 }

 // MARK: - Diagnostics support
@@ -12,6 +12,10 @@ final class ConversationUIModel: ObservableObject {
    @Published private(set) var currentNickname: String
    @Published private(set) var isBatchingPublic = false
    @Published private(set) var canSendMediaInCurrentContext = true
+    @Published private(set) var legacyPrivateMediaConsentRequest: LegacyPrivateMediaConsentRequest?
+    /// Who is talking live in the public mesh channel right now (floor
+    /// courtesy: the composer mic tints "busy" while someone holds the floor).
+    @Published private(set) var activeLiveVoiceTalker: String?

    private let chatViewModel: ChatViewModel
    private let privateConversationModel: PrivateConversationModel
@@ -150,6 +154,24 @@ final class ConversationUIModel: ObservableObject {
        chatViewModel.sendVoiceNote(at: url)
    }

+    func resolveLegacyPrivateMediaConsent(requestID: UUID, approved: Bool) {
+        chatViewModel.resolveLegacyPrivateMediaConsent(
+            requestID: requestID,
+            approved: approved
+        )
+    }
+
+    /// Capture backend for the mic gesture: live PTT when the current DM
+    /// peer can hear it now, classic voice note otherwise.
+    func makeVoiceCaptureSession() -> VoiceCaptureSession {
+        chatViewModel.makeVoiceCaptureSession()
+    }
+
+    /// Whether this message is a live voice burst still streaming in.
+    func isLiveVoiceMessage(_ message: BitchatMessage) -> Bool {
+        chatViewModel.liveVoiceCoordinator.isLiveVoiceMessage(message)
+    }
+
    func cancelMediaSend(messageID: String) {
        chatViewModel.cancelMediaSend(messageID: messageID)
    }
@@ -175,6 +197,14 @@ final class ConversationUIModel: ObservableObject {
            .receive(on: DispatchQueue.main)
            .assign(to: &$isBatchingPublic)

+        chatViewModel.$activePublicVoiceTalker
+            .receive(on: DispatchQueue.main)
+            .assign(to: &$activeLiveVoiceTalker)
+
+        chatViewModel.$legacyPrivateMediaConsentRequest
+            .receive(on: DispatchQueue.main)
+            .assign(to: &$legacyPrivateMediaConsentRequest)
+
        conversations.$activeChannel
            .receive(on: DispatchQueue.main)
            .sink { [weak self] channel in
@@ -1,4 +1,3 @@
-import BitFoundation
 import Combine
 import Foundation

@@ -17,7 +16,6 @@ final class LocationChannelsModel: ObservableObject {
    private let manager: LocationChannelManager
    private let network: NetworkActivationService
    private let gateway: GatewayService
-    private var cancellables = Set<AnyCancellable>()

    init(
        manager: LocationChannelManager? = nil,
@@ -102,10 +100,6 @@ final class LocationChannelsModel: ObservableObject {
        network.setUserTorEnabled(enabled)
    }

-    func setGatewayEnabled(_ enabled: Bool) {
-        gateway.setEnabled(enabled)
-    }
-
    func refreshMeshChannelsIfNeeded() {
        guard case .mesh = selectedChannel,
              permissionState == .authorized,
@@ -7,45 +7,146 @@ final class LocationPresenceStore: ObservableObject {
    @Published private(set) var geoNicknames: [String: String] = [:]
    @Published private(set) var teleportedGeo: Set<String> = []

+    private let teleportedGeoCapacity: Int
+    private var teleportedGeoOrder: [String] = []
+    private let geoNicknameCapacity: Int
+    private var geoNicknameOrder: [String] = []
+
+    init(
+        teleportedGeoCapacity: Int = TransportConfig.geoTeleportedParticipantsCap,
+        geoNicknameCapacity: Int = TransportConfig.geoNicknameParticipantsCap
+    ) {
+        self.teleportedGeoCapacity = max(0, teleportedGeoCapacity)
+        self.geoNicknameCapacity = max(0, geoNicknameCapacity)
+    }
+
    func setCurrentGeohash(_ geohash: String?) {
-        currentGeohash = geohash?.lowercased()
+        let normalized = geohash?.lowercased()
+        if currentGeohash != normalized {
+            // Presence markers are scoped to the active geohash channel.
+            clearTeleportedGeo()
+            clearGeoNicknames()
+        }
+        currentGeohash = normalized
    }

    func setNickname(_ nickname: String, for pubkeyHex: String) {
-        geoNicknames[pubkeyHex.lowercased()] = nickname
+        guard geoNicknameCapacity > 0 else {
+            clearGeoNicknames()
+            return
+        }
+
+        let key = pubkeyHex.lowercased()
+        if geoNicknames[key] != nil {
+            geoNicknames[key] = nickname
+            return
+        }
+
+        while geoNicknameOrder.count >= geoNicknameCapacity, let oldest = geoNicknameOrder.first {
+            geoNicknameOrder.removeFirst()
+            geoNicknames.removeValue(forKey: oldest)
+        }
+
+        geoNicknames[key] = nickname
+        geoNicknameOrder.append(key)
    }

    func replaceGeoNicknames(_ nicknames: [String: String]) {
-        geoNicknames = Dictionary(
-            uniqueKeysWithValues: nicknames.map { key, value in
-                (key.lowercased(), value)
+        guard geoNicknameCapacity > 0 else {
+            clearGeoNicknames()
+            return
        }
-        )
+
+        var seen: Set<String> = []
+        var ordered: [String] = []
+        var normalized: [String: String] = [:]
+        for (key, value) in nicknames {
+            let lower = key.lowercased()
+            guard seen.insert(lower).inserted else { continue }
+            ordered.append(lower)
+            normalized[lower] = value
+        }
+        if ordered.count > geoNicknameCapacity {
+            let kept = Array(ordered.suffix(geoNicknameCapacity))
+            ordered = kept
+            normalized = Dictionary(uniqueKeysWithValues: kept.compactMap { key in
+                normalized[key].map { (key, $0) }
+            })
+        }
+        geoNicknameOrder = ordered
+        geoNicknames = normalized
    }

    func clearGeoNicknames() {
        geoNicknames.removeAll()
+        geoNicknameOrder.removeAll()
+    }
+
+    func retainGeoNicknames(keeping pubkeys: Set<String>) {
+        let allowed = Set(pubkeys.map { $0.lowercased() })
+        geoNicknameOrder = geoNicknameOrder.filter { allowed.contains($0) }
+        geoNicknames = geoNicknames.filter { allowed.contains($0.key) }
    }

    func markTeleported(_ pubkeyHex: String) {
-        teleportedGeo.insert(pubkeyHex.lowercased())
+        guard teleportedGeoCapacity > 0 else {
+            clearTeleportedGeo()
+            return
+        }
+
+        let key = pubkeyHex.lowercased()
+        guard !teleportedGeo.contains(key) else { return }
+
+        while teleportedGeoOrder.count >= teleportedGeoCapacity, let oldest = teleportedGeoOrder.first {
+            teleportedGeoOrder.removeFirst()
+            teleportedGeo.remove(oldest)
+        }
+
+        teleportedGeo.insert(key)
+        teleportedGeoOrder.append(key)
    }

    func clearTeleported(_ pubkeyHex: String) {
-        teleportedGeo.remove(pubkeyHex.lowercased())
+        let key = pubkeyHex.lowercased()
+        teleportedGeo.remove(key)
+        teleportedGeoOrder.removeAll { $0 == key }
    }

    func replaceTeleportedGeo(_ pubkeys: Set<String>) {
-        teleportedGeo = Set(pubkeys.map { $0.lowercased() })
+        guard teleportedGeoCapacity > 0 else {
+            clearTeleportedGeo()
+            return
+        }
+
+        var seen: Set<String> = []
+        var ordered: [String] = []
+        for key in pubkeys.map({ $0.lowercased() }) where !seen.contains(key) {
+            seen.insert(key)
+            ordered.append(key)
+        }
+        if ordered.count > teleportedGeoCapacity {
+            ordered = Array(ordered.suffix(teleportedGeoCapacity))
+        }
+        teleportedGeoOrder = ordered
+        teleportedGeo = Set(ordered)
+    }
+
+    func retainTeleportedGeo(keeping pubkeys: Set<String>) {
+        let allowed = Set(pubkeys.map { $0.lowercased() })
+        teleportedGeoOrder = teleportedGeoOrder.filter { allowed.contains($0) }
+        teleportedGeo = teleportedGeo.intersection(allowed)
    }

    func clearTeleportedGeo() {
        teleportedGeo.removeAll()
+        teleportedGeoOrder.removeAll()
    }

    func reset() {
        currentGeohash = nil
        geoNicknames.removeAll()
+        geoNicknameOrder.removeAll()
        teleportedGeo.removeAll()
+        teleportedGeoOrder.removeAll()
    }
 }
@@ -0,0 +1,138 @@
+//
+// NearbyNotesCounter.swift
+// bitchat
+//
+// Counts unexpired location notes left at the user's current building-level
+// geohash so the empty mesh timeline can say "📍 3 notes left here". Only
+// subscribes while a view holds it active, and only when location notes are
+// enabled and location permission is already granted (it never prompts).
+// This is free and unencumbered software released into the public domain.
+//
+
+import Combine
+import Foundation
+
+@MainActor
+final class NearbyNotesCounter: ObservableObject {
+    static let shared = NearbyNotesCounter()
+
+    @Published private(set) var noteCount = 0
+    /// Whether an explicit notes act (the empty-timeline "check for notes"
+    /// tap, opening the notices sheet's geo tab, or a successful /drop) has
+    /// unlocked the counter this session. Until then nothing subscribes:
+    /// merely looking at the mesh timeline must not open a building-precision
+    /// relay REQ that leaks location passively.
+    @Published private(set) var revealed = false
+
+    private var manager: LocationNotesManager?
+    private var managerCancellable: AnyCancellable?
+    private var channelsCancellable: AnyCancellable?
+    private var permissionCancellable: AnyCancellable?
+    private var settingCancellable: AnyCancellable?
+    private var activeHolders = 0
+    private let locationManager: LocationChannelManager
+    private let managerFactory: @MainActor (String) -> LocationNotesManager
+    private let releaseManager: @MainActor (LocationNotesManager?) -> Void
+
+    init(
+        locationManager: LocationChannelManager = .shared,
+        managerFactory: @escaping @MainActor (String) -> LocationNotesManager = { LocationNotesPool.shared.acquire($0) },
+        releaseManager: @escaping @MainActor (LocationNotesManager?) -> Void = { LocationNotesPool.shared.release($0) }
+    ) {
+        self.locationManager = locationManager
+        self.managerFactory = managerFactory
+        self.releaseManager = releaseManager
+    }
+
+    /// Whether the empty-timeline "check for notes" hint should render.
+    /// The permission gate matters: `retarget()` never subscribes without
+    /// location authorization, so offering the hint to an unauthorized
+    /// install would be a silent dead-end — tap, `revealed` flips, the hint
+    /// vanishes, and nothing else happens for the session. The hint never
+    /// prompts; it simply stays hidden until permission exists. The caller
+    /// passes its own observed permission state so the hint re-renders when
+    /// authorization changes.
+    func offersRevealHint(permissionState: LocationChannelManager.PermissionState) -> Bool {
+        !revealed && LocationNotesSettings.enabled && permissionState == .authorized
+    }
+
+    /// Marks the one explicit act that lets the counter subscribe. Sticky for
+    /// the rest of the session (the singleton's lifetime); `deactivate()`
+    /// deliberately does not reset it.
+    func reveal() {
+        guard !revealed else { return }
+        revealed = true
+        retarget()
+    }
+
+    /// Begins (or keeps) the notes subscription for the current building
+    /// geohash. Balanced by `deactivate()`; ref-counted so multiple views can
+    /// hold it.
+    func activate() {
+        activeHolders += 1
+        guard activeHolders == 1 else { return }
+        channelsCancellable = locationManager.$availableChannels
+            .receive(on: DispatchQueue.main)
+            .sink { [weak self] _ in self?.retarget() }
+        // CoreLocation can revoke authorization while the view remains
+        // mounted. `availableChannels` deliberately retains its last value,
+        // so permission must be an independent invalidation signal or the
+        // building REQ survives on stale coordinates.
+        permissionCancellable = locationManager.$permissionState
+            .receive(on: DispatchQueue.main)
+            .sink { [weak self] _ in self?.retarget() }
+        // The app-info kill switch must take effect immediately, not on the
+        // next location change or remount.
+        settingCancellable = NotificationCenter.default
+            .publisher(for: LocationNotesSettings.didChangeNotification)
+            .receive(on: DispatchQueue.main)
+            .sink { [weak self] _ in self?.retarget() }
+        retarget()
+    }
+
+    func deactivate() {
+        activeHolders = max(0, activeHolders - 1)
+        guard activeHolders == 0 else { return }
+        channelsCancellable = nil
+        permissionCancellable = nil
+        settingCancellable = nil
+        managerCancellable = nil
+        releaseManager(manager)
+        manager = nil
+        noteCount = 0
+    }
+
+    private func retarget() {
+        guard activeHolders > 0,
+              revealed,
+              LocationNotesSettings.enabled,
+              locationManager.permissionState == .authorized,
+              let geohash = locationManager.availableChannels
+                  .first(where: { $0.level == .building })?.geohash
+        else {
+            managerCancellable = nil
+            releaseManager(manager)
+            manager = nil
+            noteCount = 0
+            return
+        }
+
+        if let manager {
+            guard manager.geohash != geohash.lowercased() else { return }
+            // Pooled managers are shared; never retarget one in place —
+            // release the old cell and acquire the new one.
+            managerCancellable = nil
+            releaseManager(manager)
+            self.manager = nil
+        }
+
+        let fresh = managerFactory(geohash)
+        manager = fresh
+        managerCancellable = fresh.$notes
+            .receive(on: DispatchQueue.main)
+            .sink { [weak self] notes in
+                let now = Date()
+                self?.noteCount = notes.filter { $0.expiresAt.map { $0 > now } ?? true }.count
+            }
+    }
+}
@@ -25,10 +25,6 @@ final class PeerIdentityStore: ObservableObject {
        stablePeerIDsByShortID[peerID] = stablePeerID
    }

-    func replaceStablePeerIDs(_ mappings: [PeerID: PeerID]) {
-        stablePeerIDsByShortID = mappings
-    }
-
    func fingerprint(for peerID: PeerID) -> String? {
        peerFingerprintsByPeerID[peerID]
    }
@@ -94,10 +90,6 @@ final class PeerIdentityStore: ObservableObject {
        invalidateEncryptionCache(for: peerID)
    }

-    func replaceEncryptionStatuses(_ statuses: [PeerID: EncryptionStatus]) {
-        encryptionStatuses = statuses
-    }
-
    func setVerifiedFingerprints(_ fingerprints: Set<String>) {
        verifiedFingerprints = fingerprints
    }
@@ -250,7 +250,7 @@ final class PrivateConversationModel: ObservableObject {
            if let group = chatViewModel.groupStore.group(for: conversationPeerID) {
                displayName = "#\(group.name) (\(group.members.count))"
            } else {
-                displayName = String(localized: "common.unknown", defaultValue: "unknown", comment: "Fallback label for unknown peer")
+                displayName = String(localized: "common.unknown", comment: "Fallback label for unknown peer")
            }
            return PrivateConversationHeaderState(
                conversationPeerID: conversationPeerID,
@@ -265,10 +265,10 @@ final class PrivateConversationModel: ObservableObject {
        let headerPeerID = chatViewModel.getShortIDForNoiseKey(conversationPeerID)
        let peer = chatViewModel.getPeer(byID: headerPeerID)
        let displayName = resolveDisplayName(for: conversationPeerID, headerPeerID: headerPeerID, peer: peer)
-        // Geo DMs are always routed over Nostr (NIP-17); their nostr_ keys
-        // never resolve to a reachable mesh peer, so resolveAvailability would
-        // report .offline. Report .nostrAvailable so the header shows the
-        // globe instead of a misleading "offline" tag.
+        // Geo DMs are always routed through BitChat private envelopes over
+        // Nostr; their nostr_ keys never resolve to a reachable mesh peer, so
+        // resolveAvailability would report .offline. Report .nostrAvailable
+        // so the header shows the globe instead of a misleading "offline" tag.
        let availability = conversationPeerID.isGeoDM
            ? .nostrAvailable
            : resolveAvailability(for: headerPeerID, peer: peer)
@@ -328,7 +328,7 @@ final class PrivateConversationModel: ObservableObject {
            }
        }

-        return String(localized: "common.unknown", defaultValue: "unknown", comment: "Fallback label for unknown peer")
+        return String(localized: "common.unknown", comment: "Fallback label for unknown peer")
    }

    private func resolveAvailability(for headerPeerID: PeerID, peer: BitchatPeer?) -> PrivateConversationAvailability {
@@ -3,7 +3,6 @@ import Combine
 import Foundation

 struct FingerprintPresentationState: Equatable {
-    let statusPeerID: PeerID
    let peerNickname: String
    let encryptionStatus: EncryptionStatus
    let theirFingerprint: String?
@@ -56,10 +55,6 @@ final class VerificationModel: ObservableObject {
        return VerificationService.shared.buildMyQRString(nickname: currentNickname, npub: npub) ?? ""
    }

-    func beginQRVerification(with qr: VerificationService.VerificationQR) -> Bool {
-        chatViewModel.beginQRVerification(with: qr)
-    }
-
    func verifyScannedPayload(_ payload: String) -> VerificationScanOutcome {
        guard let qr = VerificationService.shared.verifyScannedQR(payload) else {
            return .invalid
@@ -110,7 +105,6 @@ final class VerificationModel: ObservableObject {
        }

        return FingerprintPresentationState(
-            statusPeerID: statusPeerID,
            peerNickname: peerNickname,
            encryptionStatus: encryptionStatus,
            theirFingerprint: theirFingerprint,
@@ -186,6 +180,6 @@ final class VerificationModel: ObservableObject {
            }
        }

-        return String(localized: "common.unknown", defaultValue: "unknown", comment: "Label for an unknown peer")
+        return String(localized: "common.unknown", comment: "Label for an unknown peer")
    }
 }
@@ -27,6 +27,66 @@
      "idiom" : "universal",
      "platform" : "ios",
      "size" : "1024x1024"
+    },
+    {
+      "filename" : "mac_16x16.png",
+      "idiom" : "mac",
+      "scale" : "1x",
+      "size" : "16x16"
+    },
+    {
+      "filename" : "mac_16x16@2x.png",
+      "idiom" : "mac",
+      "scale" : "2x",
+      "size" : "16x16"
+    },
+    {
+      "filename" : "mac_32x32.png",
+      "idiom" : "mac",
+      "scale" : "1x",
+      "size" : "32x32"
+    },
+    {
+      "filename" : "mac_32x32@2x.png",
+      "idiom" : "mac",
+      "scale" : "2x",
+      "size" : "32x32"
+    },
+    {
+      "filename" : "mac_128x128.png",
+      "idiom" : "mac",
+      "scale" : "1x",
+      "size" : "128x128"
+    },
+    {
+      "filename" : "mac_128x128@2x.png",
+      "idiom" : "mac",
+      "scale" : "2x",
+      "size" : "128x128"
+    },
+    {
+      "filename" : "mac_256x256.png",
+      "idiom" : "mac",
+      "scale" : "1x",
+      "size" : "256x256"
+    },
+    {
+      "filename" : "mac_256x256@2x.png",
+      "idiom" : "mac",
+      "scale" : "2x",
+      "size" : "256x256"
+    },
+    {
+      "filename" : "mac_512x512.png",
+      "idiom" : "mac",
+      "scale" : "1x",
+      "size" : "512x512"
+    },
+    {
+      "filename" : "mac_512x512@2x.png",
+      "idiom" : "mac",
+      "scale" : "2x",
+      "size" : "512x512"
    }
  ],
  "info" : {
@@ -8,9 +8,6 @@

 import SwiftUI
 import UserNotifications
-#if DEBUG
-import BitLogger
-#endif

@main
 struct BitchatApp: App {
@@ -43,14 +40,10 @@ struct BitchatApp: App {
                .environmentObject(runtime.locationChannelsModel)
                .environmentObject(runtime.peerListModel)
                .environmentObject(runtime.appChromeModel)
+                .environmentObject(runtime.boardAlertsModel)
                .onAppear {
                    appDelegate.runtime = runtime
                    runtime.start()
-                    #if DEBUG
-                    // Arm the opt-in UDP log sink from persisted config (no-op
-                    // until a collector host is set in the App Info sheet).
-                    LogNetworkSink.shared.reloadConfiguration()
-                    #endif
                }
                .onOpenURL { url in
                    runtime.handleOpenURL(url)
@@ -111,13 +104,21 @@ final class NotificationDelegate: NSObject, UNUserNotificationCenterDelegate {

    func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {
        let identifier = response.notification.request.identifier
+        let actionIdentifier = response.actionIdentifier
        let userInfo = response.notification.request.content.userInfo

+        // Complete only after the response is handled: for a background
+        // action (👋 wave) the system may suspend the app the moment the
+        // completion handler runs, which would drop the queued send.
        Task { @MainActor in
-            self.runtime?.handleNotificationResponse(identifier: identifier, userInfo: userInfo)
-        }
+            self.runtime?.handleNotificationResponse(
+                identifier: identifier,
+                actionIdentifier: actionIdentifier,
+                userInfo: userInfo
+            )
            completionHandler()
        }
+    }

    func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
        let identifier = notification.request.identifier
@@ -0,0 +1,472 @@
+//
+// AudioSessionCoordinator.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import AVFoundation
+import BitLogger
+import Foundation
+
+/// The raw audio-session calls the coordinator makes, abstracted so the
+/// state machine is unit-testable with a mock (and compiles on the macOS
+/// test host, where `AVAudioSession` doesn't exist).
+///
+/// Calls arrive on the coordinator's private serial queue — never the main
+/// thread. `setCategory`/`setActive` block on IPC to the audio server
+/// (observed >1 s under contention on device, tripping the system gesture
+/// gate), and Apple explicitly recommends activating the session off the
+/// main thread.
+protocol SessionApplying: Sendable {
+    func setCategory(_ category: AudioSessionCoordinator.Category) throws
+    func setActive(_ active: Bool, notifyOthersOnDeactivation: Bool) throws
+}
+
+/// Sole owner of `AVAudioSession` category/activation for voice features.
+///
+/// Talk-over means capture (push-to-talk) and playback (inbound bursts,
+/// voice notes) can be live simultaneously; letting each engine configure
+/// the shared session directly made them stomp each other's category and
+/// route mid-flight (the AURemoteIO -10851 dead-input class). Instead every
+/// client acquires a `Token` and the coordinator:
+///
+/// - reference-counts activation: `setActive(true)` only on the first
+///   holder, `setActive(false, notifyOthersOnDeactivation:)` only when the
+///   last one releases — no client can deactivate another's session;
+/// - keeps one escalating category: playback-only holders get `.playback`,
+///   any capture holder escalates to `.playAndRecord`, and the category is
+///   never downgraded while anyone still holds a token (capture ending must
+///   not yank the route out from under live playback);
+/// - fans out `onInterrupted` on system interruptions and when the active
+///   route's device disappears (no auto-resume: bursts are transient, the
+///   next press or burst simply re-acquires). The escalating category change
+///   fans out separately as `onCategoryEscalated` — the session stays live,
+///   so holders that can rebuild their engine against the new configuration
+///   keep playing (talk-over is bidirectional); holders that don't provide
+///   it fall back to `onInterrupted`.
+///
+/// Threading: all state lives on a private serial queue, which both
+/// serializes rapid acquire/release pairs and keeps the blocking session IPC
+/// off the main thread (`acquire` is `async` for exactly that hop; `release`
+/// is fire-and-forget onto the queue). Holder callbacks always run on the
+/// main actor.
+///
+/// Microphone *permission* queries stay with their callers; this type owns
+/// only category and activation.
+///
+/// `@unchecked Sendable`: every mutable property is confined to `queue`.
+final class AudioSessionCoordinator: @unchecked Sendable {
+    enum Use {
+        case playback
+        case capture
+    }
+
+    /// The session category the coordinator has applied (the `SessionApplying`
+    /// adapter maps these to concrete `AVAudioSession` category/mode/options).
+    enum Category {
+        case playback
+        case playAndRecord
+    }
+
+    /// Opaque handle for one client's hold on the session. Release exactly
+    /// once when done (extra releases are ignored).
+    ///
+    /// `@unchecked` because the stored callbacks are `@MainActor`-isolated
+    /// closures (non-Sendable as stored types). Lifecycle state is protected
+    /// by `stateLock`, and callbacks are only ever invoked on the main actor.
+    final class Token: @unchecked Sendable {
+        fileprivate enum CallbackKind: Sendable {
+            case interrupted
+            case categoryEscalated
+        }
+
+        /// A callback snapshot is only valid for the lifecycle epoch in which
+        /// it was captured. `release` advances the epoch synchronously before
+        /// its queue work, so a callback already headed to the main actor can't
+        /// reach a client that has since released this token and reacquired a
+        /// different one.
+        fileprivate struct CallbackTicket: Sendable {
+            let token: Token
+            let kind: CallbackKind
+            let lifecycleEpoch: UInt64
+        }
+
+        private enum Lifecycle {
+            /// Registered on the session queue, but `acquire` has not yet
+            /// returned into the client's main-actor call frame.
+            case acquiring
+            case ready
+            case released
+        }
+
+        fileprivate let onInterrupted: @MainActor () -> Void
+        fileprivate let onCategoryEscalated: (@MainActor () -> Void)?
+        private let stateLock = NSLock()
+        private var lifecycle = Lifecycle.acquiring
+        private var lifecycleEpoch: UInt64 = 0
+        /// A terminal event that lands while the token is registered but not
+        /// yet handed off invalidates the acquire before its caller can start.
+        private var terminalEventPendingHandoff = false
+
+        fileprivate init(
+            onInterrupted: @escaping @MainActor () -> Void,
+            onCategoryEscalated: (@MainActor () -> Void)?
+        ) {
+            self.onInterrupted = onInterrupted
+            self.onCategoryEscalated = onCategoryEscalated
+        }
+
+        /// Records an event at the same linearization point at which the
+        /// coordinator snapshots its holders. An acquiring token cannot safely
+        /// receive a callback yet: terminal events invalidate the acquire,
+        /// while category escalation needs no callback because its engine will
+        /// start against the already-escalated configuration.
+        fileprivate func record(_ kind: CallbackKind) -> CallbackTicket? {
+            stateLock.withLock {
+                switch lifecycle {
+                case .acquiring:
+                    switch kind {
+                    case .interrupted:
+                        terminalEventPendingHandoff = true
+                    case .categoryEscalated:
+                        break
+                    }
+                    return nil
+                case .ready:
+                    return CallbackTicket(token: self, kind: kind, lifecycleEpoch: lifecycleEpoch)
+                case .released:
+                    return nil
+                }
+            }
+        }
+
+        /// Completes the main-actor ownership handoff if no terminal event
+        /// invalidated it. Because `acquire` itself is main-actor isolated, a
+        /// successful handoff returns directly into the caller without another
+        /// actor hop; no callback can interleave before the caller stores the
+        /// returned token.
+        fileprivate func completeHandoff() -> Bool {
+            stateLock.withLock {
+                guard lifecycle == .acquiring,
+                      !terminalEventPendingHandoff
+                else { return false }
+                lifecycle = .ready
+                return true
+            }
+        }
+
+        /// Marks the token dead synchronously, before the asynchronous holder
+        /// removal. Returns false for an already-released token.
+        fileprivate func markReleased() -> Bool {
+            stateLock.withLock {
+                guard lifecycle != .released else { return false }
+                lifecycle = .released
+                lifecycleEpoch &+= 1
+                terminalEventPendingHandoff = false
+                return true
+            }
+        }
+
+        /// Revalidates a queue snapshot at the main-actor delivery boundary.
+        /// The lock is deliberately released before invoking client code: real
+        /// callbacks commonly call `release` on this same token.
+        @MainActor
+        fileprivate func deliver(_ ticket: CallbackTicket) {
+            let isLive = stateLock.withLock {
+                lifecycle == .ready && lifecycleEpoch == ticket.lifecycleEpoch
+            }
+            guard isLive else { return }
+            switch ticket.kind {
+            case .interrupted:
+                onInterrupted()
+            case .categoryEscalated:
+                (onCategoryEscalated ?? onInterrupted)()
+            }
+        }
+    }
+
+    /// Deterministic suspension points for lifecycle race tests. Production
+    /// instances use the nil defaults; the hooks never move session calls off
+    /// the coordinator queue or callback execution off the main actor.
+    struct TestingHooks: Sendable {
+        let beforeAcquireHandoff: (@Sendable () async -> Void)?
+        let beforeCallbackDelivery: (@Sendable () async -> Void)?
+
+        init(
+            beforeAcquireHandoff: (@Sendable () async -> Void)? = nil,
+            beforeCallbackDelivery: (@Sendable () async -> Void)? = nil
+        ) {
+            self.beforeAcquireHandoff = beforeAcquireHandoff
+            self.beforeCallbackDelivery = beforeCallbackDelivery
+        }
+    }
+
+    static let shared = AudioSessionCoordinator(session: SystemAudioSession())
+
+    private let session: SessionApplying
+    private let testingHooks: TestingHooks
+    /// Confines all mutable state, serializes whole acquire/release
+    /// operations (two rapid presses can't interleave their category and
+    /// activation calls), and hosts the blocking session IPC off main.
+    private let queue = DispatchQueue(label: "chat.bitchat.audio-session", qos: .userInitiated)
+
+    // Queue-confined state.
+    private var holders: [ObjectIdentifier: Token] = [:]
+    private var currentCategory: Category?
+    private var sessionActive = false
+    /// Written once in init, read in deinit — never touched concurrently.
+    private var observers: [NSObjectProtocol] = []
+
+    init(session: SessionApplying, testingHooks: TestingHooks = TestingHooks()) {
+        self.session = session
+        self.testingHooks = testingHooks
+        observeSystemNotifications()
+    }
+
+    deinit {
+        for observer in observers {
+            NotificationCenter.default.removeObserver(observer)
+        }
+    }
+
+    /// Configures + activates the session for `use` and registers the caller
+    /// as a holder. The blocking `AVAudioSession` calls run on the session
+    /// queue — the caller suspends instead of stalling its thread (a PTT
+    /// press used to block main >1 s in `setActive`, tripping the system
+    /// gesture gate). `onInterrupted` fires (on the main actor) when the
+    /// client must stop using the session: a system interruption began or
+    /// its route's device went away. The client should stop its engine,
+    /// finalize any artifacts, and release — resuming means acquiring again.
+    ///
+    /// `onCategoryEscalated` fires instead when the session category
+    /// escalated underneath the holder (a capture client joined): the session
+    /// stays active, so a holder that can rebuild its engine against the new
+    /// configuration should restart and keep going. Holders that pass `nil`
+    /// get `onInterrupted` for escalation too. Escalation is delivered before
+    /// `acquire` returns, so the new holder starts its engine strictly after
+    /// existing ones were told to rebuild. Main-actor isolation is also the
+    /// ownership handoff boundary: if interruption or route loss lands after
+    /// queue registration but before that boundary, the provisional holder is
+    /// removed and `acquire` throws `CancellationError` instead of returning a
+    /// token whose callback already fired.
+    @MainActor
+    func acquire(
+        _ use: Use,
+        onInterrupted: @escaping @MainActor () -> Void,
+        onCategoryEscalated: (@MainActor () -> Void)? = nil
+    ) async throws -> Token {
+        let token = Token(onInterrupted: onInterrupted, onCategoryEscalated: onCategoryEscalated)
+        let reconfigured: [Token.CallbackTicket] = try await withCheckedThrowingContinuation { continuation in
+            queue.async {
+                do {
+                    continuation.resume(returning: try self.activateOnQueue(use, registering: token))
+                } catch {
+                    continuation.resume(throwing: error)
+                }
+            }
+        }
+
+        // Escalating playback -> playAndRecord reconfigures the hardware
+        // route; engines started against the old configuration must restart.
+        if !reconfigured.isEmpty {
+            SecureLogger.info("AudioSession: category escalated to playAndRecord with \(reconfigured.count) live holder(s)", category: .session)
+            await deliver(reconfigured)
+        }
+        if let beforeAcquireHandoff = testingHooks.beforeAcquireHandoff {
+            await beforeAcquireHandoff()
+        }
+        guard token.completeHandoff() else {
+            // A call/Siri interruption or route loss landed after registration
+            // but before ownership handoff. Remove the provisional holder and
+            // fail instead of starting a client engine after the stop event.
+            release(token)
+            throw CancellationError()
+        }
+        return token
+    }
+
+    /// Drops one holder. Deactivates the session (notifying other apps) only
+    /// when the last holder releases. Safe to call more than once, from any
+    /// thread (including `deinit` paths): the work is fire-and-forget onto
+    /// the session queue, so the blocking deactivation IPC never runs on the
+    /// caller.
+    func release(_ token: Token) {
+        guard token.markReleased() else { return }
+        queue.async {
+            self.releaseOnQueue(token)
+        }
+    }
+
+    // MARK: - Queue-confined core
+
+    /// Returns callback tickets for pre-existing live holders whose engines
+    /// must restart because this acquire escalated the category.
+    private func activateOnQueue(_ use: Use, registering token: Token) throws -> [Token.CallbackTicket] {
+        let target: Category = (use == .capture || currentCategory == .playAndRecord) ? .playAndRecord : .playback
+        let categoryChanged = target != currentCategory
+        let previousCategory = currentCategory
+        if categoryChanged {
+            try session.setCategory(target)
+            currentCategory = target
+        }
+        if !sessionActive {
+            do {
+                try session.setActive(true, notifyOthersOnDeactivation: false)
+            } catch {
+                // Activation failed (e.g. a phone call owns the hardware):
+                // with no holder registered, an escalated category recorded
+                // here would stick and pin later playback-only acquires to
+                // .playAndRecord. Existing holders keep the category the
+                // hardware really has.
+                if categoryChanged, holders.isEmpty {
+                    currentCategory = previousCategory
+                }
+                throw error
+            }
+            sessionActive = true
+        }
+
+        let reconfigured = categoryChanged
+            ? holders.values.compactMap { $0.record(.categoryEscalated) }
+            : []
+        holders[ObjectIdentifier(token)] = token
+        return reconfigured
+    }
+
+    private func releaseOnQueue(_ token: Token) {
+        guard holders.removeValue(forKey: ObjectIdentifier(token)) != nil else { return }
+        guard holders.isEmpty else { return }
+        currentCategory = nil
+        guard sessionActive else { return }
+        sessionActive = false
+        do {
+            try session.setActive(false, notifyOthersOnDeactivation: true)
+        } catch {
+            SecureLogger.error("AudioSession: deactivation failed: \(error)", category: .session)
+        }
+    }
+
+    private func onQueue<T: Sendable>(_ body: @escaping @Sendable () -> T) async -> T {
+        await withCheckedContinuation { continuation in
+            queue.async {
+                continuation.resume(returning: body())
+            }
+        }
+    }
+
+    @MainActor
+    private func deliver(_ tickets: [Token.CallbackTicket]) async {
+        guard !tickets.isEmpty else { return }
+        if let beforeCallbackDelivery = testingHooks.beforeCallbackDelivery {
+            await beforeCallbackDelivery()
+        }
+        for ticket in tickets {
+            ticket.token.deliver(ticket)
+        }
+    }
+
+    // MARK: - System events (internal so tests can drive them directly)
+
+    /// A system interruption began: the session is already deactivated by the
+    /// OS, so just mark it inactive and tell every ready holder (on the main
+    /// actor) to stop. A provisional acquiring holder is invalidated instead.
+    /// No auto-resume — the next acquire re-activates.
+    func handleInterruptionBegan() async {
+        let tickets = await onQueue { () -> [Token.CallbackTicket] in
+            self.sessionActive = false
+            return self.holders.values.compactMap { $0.record(.interrupted) }
+        }
+        await deliver(tickets)
+    }
+
+    /// The active route's input/output device disappeared (e.g. BT headset
+    /// off): ready holders' engines are wedged against a dead route — stop
+    /// them; invalidate a holder whose acquire has not returned yet.
+    func handleRouteDeviceUnavailable() async {
+        let tickets = await onQueue {
+            self.holders.values.compactMap { $0.record(.interrupted) }
+        }
+        await deliver(tickets)
+    }
+
+    /// Test hook: suspends until every session operation enqueued before this
+    /// call — including fire-and-forget `release`s — has completed.
+    func drain() async {
+        await onQueue {}
+    }
+
+    private func observeSystemNotifications() {
+        #if os(iOS)
+        let center = NotificationCenter.default
+        observers.append(center.addObserver(
+            forName: AVAudioSession.interruptionNotification,
+            object: AVAudioSession.sharedInstance(),
+            queue: .main
+        ) { [weak self] note in
+            guard let raw = note.userInfo?[AVAudioSessionInterruptionTypeKey] as? UInt,
+                  AVAudioSession.InterruptionType(rawValue: raw) == .began,
+                  let self
+            else { return }
+            SecureLogger.info("AudioSession: interruption began", category: .session)
+            Task { await self.handleInterruptionBegan() }
+        })
+        observers.append(center.addObserver(
+            forName: AVAudioSession.routeChangeNotification,
+            object: AVAudioSession.sharedInstance(),
+            queue: .main
+        ) { [weak self] note in
+            guard let raw = note.userInfo?[AVAudioSessionRouteChangeReasonKey] as? UInt,
+                  AVAudioSession.RouteChangeReason(rawValue: raw) == .oldDeviceUnavailable,
+                  let self
+            else { return }
+            SecureLogger.info("AudioSession: route device became unavailable", category: .session)
+            Task { await self.handleRouteDeviceUnavailable() }
+        })
+        #endif
+    }
+}
+
+// MARK: - Production adapter
+
+#if os(iOS)
+private struct SystemAudioSession: SessionApplying {
+    func setCategory(_ category: AudioSessionCoordinator.Category) throws {
+        let session = AVAudioSession.sharedInstance()
+        switch category {
+        case .playback:
+            try session.setCategory(.playback, mode: .spokenAudio, options: [.mixWithOthers])
+        case .playAndRecord:
+            // allowBluetoothHFP is not available on iOS Simulator
+            #if targetEnvironment(simulator)
+            try session.setCategory(
+                .playAndRecord,
+                mode: .default,
+                options: [.defaultToSpeaker, .allowBluetoothA2DP, .mixWithOthers]
+            )
+            #else
+            try session.setCategory(
+                .playAndRecord,
+                mode: .default,
+                options: [.defaultToSpeaker, .allowBluetoothA2DP, .allowBluetoothHFP, .mixWithOthers]
+            )
+            #endif
+        }
+    }
+
+    func setActive(_ active: Bool, notifyOthersOnDeactivation: Bool) throws {
+        try AVAudioSession.sharedInstance().setActive(
+            active,
+            options: notifyOthersOnDeactivation ? [.notifyOthersOnDeactivation] : []
+        )
+    }
+}
+#else
+/// macOS has no app-level audio session; the coordinator still runs its
+/// bookkeeping so client code is identical across platforms.
+private struct SystemAudioSession: SessionApplying {
+    func setCategory(_ category: AudioSessionCoordinator.Category) throws {}
+    func setActive(_ active: Bool, notifyOthersOnDeactivation: Bool) throws {}
+}
+#endif
@@ -0,0 +1,175 @@
+//
+// PTTAudioCodec.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import AVFoundation
+import BitLogger
+import Foundation
+
+/// Streaming PCM -> AAC-LC encoder for live voice. Stateful (the AAC encoder
+/// carries a bit reservoir across frames); one instance per burst.
+/// Not thread-safe — confine to one queue.
+final class PTTFrameEncoder {
+    private let converter: AVAudioConverter
+    private var pendingInput: [AVAudioPCMBuffer] = []
+
+    init?() {
+        guard let pcm = PTTAudioFormat.pcmFormat,
+              let aac = PTTAudioFormat.aacFormat,
+              let converter = AVAudioConverter(from: pcm, to: aac)
+        else { return nil }
+        converter.bitRate = PTTAudioFormat.bitRate
+        self.converter = converter
+    }
+
+    /// Feeds PCM (16 kHz mono float) and returns every complete AAC frame the
+    /// encoder produced. Frames come out ~130 bytes each at 16 kbps.
+    func encode(_ buffer: AVAudioPCMBuffer) -> [Data] {
+        pendingInput.append(buffer)
+        return drainConverter()
+    }
+
+    private func drainConverter() -> [Data] {
+        var frames: [Data] = []
+        while true {
+            let output = AVAudioCompressedBuffer(
+                format: converter.outputFormat,
+                packetCapacity: 8,
+                maximumPacketSize: max(converter.maximumOutputPacketSize, 1)
+            )
+            var error: NSError?
+            let status = converter.convert(to: output, error: &error) { [weak self] _, outStatus in
+                guard let self, let next = self.pendingInput.first else {
+                    outStatus.pointee = .noDataNow
+                    return nil
+                }
+                self.pendingInput.removeFirst()
+                outStatus.pointee = .haveData
+                return next
+            }
+            if status == .error {
+                SecureLogger.error("PTT encode failed: \(error?.localizedDescription ?? "unknown")", category: .session)
+                return frames
+            }
+            frames.append(contentsOf: Self.extractPackets(from: output))
+            // .haveData means the output buffer filled and more may be ready;
+            // anything else means the converter wants more input.
+            if status != .haveData { return frames }
+        }
+    }
+
+    private static func extractPackets(from buffer: AVAudioCompressedBuffer) -> [Data] {
+        guard buffer.packetCount > 0, let descriptions = buffer.packetDescriptions else { return [] }
+        var frames: [Data] = []
+        frames.reserveCapacity(Int(buffer.packetCount))
+        for index in 0..<Int(buffer.packetCount) {
+            let description = descriptions[index]
+            guard description.mDataByteSize > 0 else { continue }
+            let start = buffer.data.advanced(by: Int(description.mStartOffset))
+            frames.append(Data(bytes: start, count: Int(description.mDataByteSize)))
+        }
+        return frames
+    }
+}
+
+/// Streaming AAC-LC -> PCM decoder for live voice. Stateful; one instance per
+/// inbound burst. Not thread-safe — confine to one queue/actor.
+final class PTTFrameDecoder {
+    private let converter: AVAudioConverter
+    private let pcmFormat: AVAudioFormat
+    private let aacFormat: AVAudioFormat
+
+    init?() {
+        guard let pcm = PTTAudioFormat.pcmFormat,
+              let aac = PTTAudioFormat.aacFormat,
+              let converter = AVAudioConverter(from: aac, to: pcm)
+        else { return nil }
+        self.converter = converter
+        self.pcmFormat = pcm
+        self.aacFormat = aac
+    }
+
+    /// Decodes one raw AAC frame to PCM. Returns nil for malformed input or
+    /// while the decoder is still priming (the first frame of a stream).
+    func decode(_ frame: Data) -> AVAudioPCMBuffer? {
+        guard !frame.isEmpty, frame.count <= 8 * 1024 else { return nil }
+
+        let input = AVAudioCompressedBuffer(format: aacFormat, packetCapacity: 1, maximumPacketSize: frame.count)
+        frame.withUnsafeBytes { raw in
+            guard let base = raw.baseAddress else { return }
+            input.data.copyMemory(from: base, byteCount: frame.count)
+        }
+        input.byteLength = UInt32(frame.count)
+        input.packetCount = 1
+        input.packetDescriptions?.pointee = AudioStreamPacketDescription(
+            mStartOffset: 0,
+            mVariableFramesInPacket: 0,
+            mDataByteSize: UInt32(frame.count)
+        )
+
+        guard let output = AVAudioPCMBuffer(
+            pcmFormat: pcmFormat,
+            frameCapacity: PTTAudioFormat.samplesPerFrame * 2
+        ) else { return nil }
+
+        var consumed = false
+        var error: NSError?
+        let status = converter.convert(to: output, error: &error) { _, outStatus in
+            if consumed {
+                outStatus.pointee = .noDataNow
+                return nil
+            }
+            consumed = true
+            outStatus.pointee = .haveData
+            return input
+        }
+        guard status != .error else {
+            SecureLogger.debug("PTT decode failed: \(error?.localizedDescription ?? "unknown")", category: .session)
+            return nil
+        }
+        return output.frameLength > 0 ? output : nil
+    }
+}
+
+/// Sample-rate/channel converter from the microphone's native format to the
+/// 16 kHz mono processing format. Stateful; not thread-safe.
+final class PTTInputResampler {
+    private let converter: AVAudioConverter
+    private let outputFormat: AVAudioFormat
+    private let ratio: Double
+
+    init?(inputFormat: AVAudioFormat) {
+        guard let pcm = PTTAudioFormat.pcmFormat,
+              let converter = AVAudioConverter(from: inputFormat, to: pcm)
+        else { return nil }
+        self.converter = converter
+        self.outputFormat = pcm
+        self.ratio = PTTAudioFormat.sampleRate / inputFormat.sampleRate
+    }
+
+    func resample(_ buffer: AVAudioPCMBuffer) -> AVAudioPCMBuffer? {
+        let capacity = AVAudioFrameCount(Double(buffer.frameLength) * ratio) + 64
+        guard let output = AVAudioPCMBuffer(pcmFormat: outputFormat, frameCapacity: capacity) else { return nil }
+
+        var consumed = false
+        var error: NSError?
+        let status = converter.convert(to: output, error: &error) { _, outStatus in
+            if consumed {
+                outStatus.pointee = .noDataNow
+                return nil
+            }
+            consumed = true
+            outStatus.pointee = .haveData
+            return buffer
+        }
+        guard status != .error else {
+            SecureLogger.debug("PTT resample failed: \(error?.localizedDescription ?? "unknown")", category: .session)
+            return nil
+        }
+        return output.frameLength > 0 ? output : nil
+    }
+}
@@ -0,0 +1,84 @@
+//
+// PTTAudioFormat.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import AVFoundation
+import Foundation
+
+/// Shared audio parameters for live push-to-talk: AAC-LC, 16 kHz, mono,
+/// ~16 kbps — deliberately identical to `VoiceRecorder`'s voice-note settings
+/// so a burst's finalized `.m4a` and its live frames sound the same.
+enum PTTAudioFormat {
+    static let sampleRate: Double = 16_000
+    static let channelCount: AVAudioChannelCount = 1
+    static let bitRate = 16_000
+    /// AAC-LC frame size is fixed by the codec: 1024 samples = 64 ms at 16 kHz.
+    static let samplesPerFrame: AVAudioFrameCount = 1024
+    static var frameDuration: TimeInterval { Double(samplesPerFrame) / sampleRate }
+
+    /// Uncompressed processing format (deinterleaved float PCM).
+    static var pcmFormat: AVAudioFormat? {
+        AVAudioFormat(standardFormatWithSampleRate: sampleRate, channels: channelCount)
+    }
+
+    /// Compressed wire format.
+    static var aacFormat: AVAudioFormat? {
+        var description = AudioStreamBasicDescription(
+            mSampleRate: sampleRate,
+            mFormatID: kAudioFormatMPEG4AAC,
+            mFormatFlags: 0,
+            mBytesPerPacket: 0,
+            mFramesPerPacket: samplesPerFrame,
+            mBytesPerFrame: 0,
+            mChannelsPerFrame: channelCount,
+            mBitsPerChannel: 0,
+            mReserved: 0
+        )
+        return AVAudioFormat(streamDescription: &description)
+    }
+
+    /// Voice-note container settings for the finalized `.m4a`, mirroring
+    /// `VoiceRecorder.startRecording()`.
+    static var voiceNoteFileSettings: [String: Any] {
+        [
+            AVFormatIDKey: kAudioFormatMPEG4AAC,
+            AVSampleRateKey: sampleRate,
+            AVNumberOfChannelsKey: Int(channelCount),
+            AVEncoderBitRateKey: bitRate
+        ]
+    }
+}
+
+/// Builds ADTS-framed AAC so a receiver can persist a burst progressively:
+/// unlike `.m4a` (whose moov atom only exists after close), an ADTS `.aac`
+/// stream is playable at any prefix — a partially received burst is still a
+/// replayable voice note.
+enum ADTSFramer {
+    private static let headerSize = 7
+    /// MPEG-4 sampling frequency index for 16 kHz.
+    private static let samplingFrequencyIndex: UInt8 = 8
+    private static let channelConfiguration: UInt8 = 1
+
+    /// Wraps one raw AAC-LC frame in an ADTS header.
+    static func frame(_ aacFrame: Data) -> Data {
+        let frameLength = aacFrame.count + headerSize
+        var data = Data(capacity: frameLength)
+        // Syncword 0xFFF, MPEG-4, layer 00, no CRC.
+        data.append(0xFF)
+        data.append(0xF1)
+        // Profile AAC-LC (audio object type 2 -> bits 01), frequency index,
+        // private bit 0, channel config high bit.
+        data.append((0b01 << 6) | (samplingFrequencyIndex << 2) | ((channelConfiguration >> 2) & 0x1))
+        data.append(((channelConfiguration & 0x3) << 6) | UInt8((frameLength >> 11) & 0x3))
+        data.append(UInt8((frameLength >> 3) & 0xFF))
+        data.append(UInt8((frameLength & 0x7) << 5) | 0x1F)
+        // Buffer fullness 0x7FF (VBR), one AAC frame per ADTS frame.
+        data.append(0xFC)
+        data.append(aacFrame)
+        return data
+    }
+}
@@ -0,0 +1,509 @@
+//
+// PTTBurstPlayer.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+@preconcurrency import AVFoundation
+import BitLogger
+import Foundation
+
+/// The engine operations behind live-burst playback, abstracted so the
+/// player's lifecycle (jitter start, category-escalation restart, stop) is
+/// unit-testable without real audio hardware.
+@MainActor
+protocol PTTPlaybackEngine: AnyObject {
+    /// The object `AVAudioEngineConfigurationChange` notifications are posted
+    /// for (nil for mocks — no observer is registered).
+    var configChangeObject: AnyObject? { get }
+    func start() throws
+    func play()
+    func stop()
+    func schedule(
+        _ buffer: AVAudioPCMBuffer,
+        completionType: PTTPlaybackCompletionType,
+        completionHandler: @escaping @Sendable (PTTPlaybackCompletionEvent) -> Void
+    )
+}
+
+/// The lifecycle point requested from `AVAudioPlayerNode` for a scheduled
+/// buffer. `dataConsumed` only means the node no longer needs the bytes; it
+/// may arrive before the render pipeline has made the audio audible.
+enum PTTPlaybackCompletionType: Equatable, Sendable {
+    case dataConsumed
+    case dataPlayedBack
+}
+
+enum PTTPlaybackCompletionEvent: Equatable, Sendable {
+    case dataConsumed
+    case dataPlayedBack
+    /// AVAudioPlayerNode invokes the requested callback when the node is
+    /// stopped too. That is not audible completion and must remain replayable.
+    case playbackStopped
+}
+
+/// One `AVAudioEngine` + `AVAudioPlayerNode` pair. Created fresh per (re)start:
+/// an engine instantiated against an earlier audio-session configuration keeps
+/// rendering to the stale route (same class of failure as the capture side's
+/// fresh-engine-per-press rule).
+@MainActor
+private final class SystemPTTPlaybackEngine: PTTPlaybackEngine {
+    private let engine = AVAudioEngine()
+    private let node = AVAudioPlayerNode()
+
+    init(format: AVAudioFormat) {
+        engine.attach(node)
+        engine.connect(node, to: engine.mainMixerNode, format: format)
+    }
+
+    var configChangeObject: AnyObject? { engine }
+
+    func start() throws {
+        engine.prepare()
+        try engine.start()
+    }
+
+    func play() {
+        node.play()
+    }
+
+    func stop() {
+        node.stop()
+        engine.stop()
+    }
+
+    func schedule(
+        _ buffer: AVAudioPCMBuffer,
+        completionType: PTTPlaybackCompletionType,
+        completionHandler: @escaping @Sendable (PTTPlaybackCompletionEvent) -> Void
+    ) {
+        let callbackType: AVAudioPlayerNodeCompletionCallbackType = switch completionType {
+        case .dataConsumed: .dataConsumed
+        case .dataPlayedBack: .dataPlayedBack
+        }
+        let scheduledEngine = engine
+        node.scheduleBuffer(buffer, completionCallbackType: callbackType) { [weak scheduledEngine] callbackType in
+            // The API invokes this callback when the player is stopped as
+            // well. A configuration change can stop the engine before its
+            // notification reaches MainActor, so do not misclassify that
+            // flushed tail as audible playback.
+            guard scheduledEngine?.isRunning == true else {
+                completionHandler(.playbackStopped)
+                return
+            }
+            switch callbackType {
+            case .dataConsumed:
+                completionHandler(.dataConsumed)
+            case .dataRendered:
+                completionHandler(.dataConsumed)
+            case .dataPlayedBack:
+                completionHandler(.dataPlayedBack)
+            @unknown default:
+                completionHandler(.playbackStopped)
+            }
+        }
+    }
+}
+
+/// Completion callbacks arrive off the main actor, while engine rebuilds are
+/// serialized on it. This small lock-backed latch lets a rebuild atomically
+/// claim only buffers whose completion has not already fired — even when the
+/// callback's hop back to the main actor is still queued.
+private final class PTTPlaybackCompletionState: @unchecked Sendable {
+    private enum State {
+        case scheduled
+        case completed
+        case retired
+    }
+
+    private let lock = NSLock()
+    private var state: State = .scheduled
+
+    /// Returns true exactly once when playback completion wins the race with
+    /// an engine rebuild or stop.
+    func complete() -> Bool {
+        lock.withLock {
+            guard case .scheduled = state else { return false }
+            state = .completed
+            return true
+        }
+    }
+
+    /// Returns true exactly once when a rebuild or stop claims this
+    /// still-pending schedule. Later callbacks from that engine are stale.
+    func retireIfPending() -> Bool {
+        lock.withLock {
+            guard case .scheduled = state else { return false }
+            state = .retired
+            return true
+        }
+    }
+}
+
+/// Plays one inbound live voice burst with a small jitter buffer.
+///
+/// Frames are decoded and scheduled back-to-back on an `AVAudioPlayerNode`;
+/// an underrun (missing/late packets) simply pauses output until the next
+/// buffer arrives, which self-heals timing without explicit silence
+/// insertion. Playback starts once `TransportConfig.pttJitterBufferSeconds`
+/// of audio is queued or `pttJitterDeadlineSeconds` has elapsed.
+///
+/// Talk-over is bidirectional: when push-to-talk capture starts while this
+/// burst plays, the session category escalates underneath the engine — the
+/// player rebuilds a fresh engine against the new configuration and keeps
+/// streaming instead of dying. Real interruptions (phone call, route device
+/// gone) still stop it; the burst keeps assembling to file either way.
+@MainActor
+final class PTTBurstPlayer {
+    /// Restart-on-reconfigure ceiling: a burst is at most ~2 minutes, so a
+    /// handful of category/route changes is plenty — beyond it something is
+    /// thrashing and stopping cleanly beats an engine-rebuild loop.
+    private static let maxEngineRestarts = 8
+
+    private let makeEngine: @MainActor () -> PTTPlaybackEngine
+    private var engine: PTTPlaybackEngine
+    private let decoder: PTTFrameDecoder
+    private let coordinator: AudioSessionCoordinator
+    /// Injectable so tests don't fight over the app-wide exclusive-playback
+    /// slot (a parallel test's `play()` would stop this player mid-test).
+    private let exclusivity: VoiceNotePlaybackCoordinator
+
+    private var queuedBuffers: [AVAudioPCMBuffer] = []
+    private var queuedDuration: TimeInterval = 0
+    private struct ScheduledBuffer {
+        let id: UInt64
+        let buffer: AVAudioPCMBuffer
+        let completionState: PTTPlaybackCompletionState
+    }
+    /// Buffers handed to the current engine whose completion has not yet
+    /// been processed on the main actor. Keeping the buffers themselves lets
+    /// a category-escalation rebuild replay the unfinished tail in order.
+    private var scheduledBuffers: [ScheduledBuffer] = []
+    private var nextScheduledBufferID: UInt64 = 0
+    /// Bumped on every engine rebuild or stop so completion tasks from a
+    /// torn-down engine cannot mutate the current generation's pending list.
+    private var engineGeneration = 0
+    private var engineRestarts = 0
+    private var engineStarted = false
+    private var finished = false
+    /// Latched off (internal read so tests can await the async failure path).
+    private(set) var stopped = false
+    /// A session acquire is in flight (it suspends off-main for the blocking
+    /// session IPC); gates `startIfReady` against double acquisition.
+    private var acquiringSession = false
+    private var deadlineTask: Task<Void, Never>?
+    private var sessionToken: AudioSessionCoordinator.Token?
+    /// Reserved before the session acquire suspends. Activation succeeds only
+    /// if no newer playback request claimed the floor in the meantime.
+    private var playbackReservation: VoiceNotePlaybackCoordinator.Reservation?
+    private var configChangeObserver: NSObjectProtocol?
+
+    private(set) var isPlaying = false
+
+    /// Fires exactly once when the player stops for good (drain-out, cancel,
+    /// interruption, failure). `ChatLiveVoiceCoordinator` uses it to unpark
+    /// the draining player it keeps alive after the assembly — the player's
+    /// only long-lived owner — is discarded on burst END.
+    var onStopped: (() -> Void)?
+
+    init?(
+        coordinator: AudioSessionCoordinator? = nil,
+        exclusivity: VoiceNotePlaybackCoordinator? = nil,
+        makeEngine: (@MainActor () -> PTTPlaybackEngine)? = nil
+    ) {
+        guard let format = PTTAudioFormat.pcmFormat, let decoder = PTTFrameDecoder() else { return nil }
+        self.decoder = decoder
+        self.coordinator = coordinator ?? .shared
+        self.exclusivity = exclusivity ?? .shared
+        let factory = makeEngine ?? { SystemPTTPlaybackEngine(format: format) }
+        self.makeEngine = factory
+        self.engine = factory()
+
+        deadlineTask = Task { [weak self] in
+            try? await Task.sleep(nanoseconds: UInt64(TransportConfig.pttJitterDeadlineSeconds * 1_000_000_000))
+            self?.startIfReady(force: true)
+        }
+    }
+
+    deinit {
+        // Backstop for an owner dropping the player before it stopped: the
+        // session coordinator retains registered tokens strongly, so a token
+        // leaked here would keep the session active (and pin any escalated
+        // category) for the app's lifetime. `release` is fire-and-forget
+        // onto the coordinator's queue, so it is deinit-safe.
+        if let token = sessionToken {
+            coordinator.release(token)
+        }
+        if let observer = configChangeObserver {
+            NotificationCenter.default.removeObserver(observer)
+        }
+        deadlineTask?.cancel()
+    }
+
+    /// Decodes and queues frames (in burst order). Starts playback when the
+    /// jitter buffer fills.
+    func enqueue(_ frames: [Data]) {
+        guard !stopped else { return }
+        for frame in frames {
+            guard let pcm = decoder.decode(frame) else { continue }
+            if engineStarted {
+                schedule(pcm)
+            } else {
+                queuedBuffers.append(pcm)
+                queuedDuration += Double(pcm.frameLength) / PTTAudioFormat.sampleRate
+            }
+        }
+        startIfReady(force: false)
+    }
+
+    /// The burst ended: stop once everything scheduled has played out.
+    func finishAfterDrain() {
+        finished = true
+        // The complete burst is queued — no jitter left to wait for. This
+        // also matters when END lands while the async session acquire is
+        // still in flight: the queued audio must play out, not be treated
+        // as already drained.
+        startIfReady(force: true)
+        stopIfDrained()
+    }
+
+    /// Immediate stop (cancel, another playback taking over, interruption,
+    /// teardown).
+    func stop() {
+        guard !stopped else { return }
+        stopped = true
+        deadlineTask?.cancel()
+        removeConfigObserver()
+        queuedBuffers = []
+        retireScheduledBuffers()
+        if engineStarted {
+            engine.stop()
+        }
+        isPlaying = false
+        releaseSessionToken()
+        exclusivity.deactivate(self)
+        onStopped?()
+    }
+
+    private func startIfReady(force: Bool) {
+        guard !engineStarted, !acquiringSession, !stopped, !queuedBuffers.isEmpty else { return }
+        guard force || queuedDuration >= TransportConfig.pttJitterBufferSeconds else { return }
+
+        // Acquiring the session suspends for its blocking IPC (off the main
+        // actor); frames arriving meanwhile keep queueing and are flushed
+        // onto the engine once it starts.
+        acquiringSession = true
+        playbackReservation = exclusivity.reserve(self)
+        Task { [weak self] in
+            await self?.acquireSessionAndStart()
+        }
+    }
+
+    private func acquireSessionAndStart() async {
+        let token: AudioSessionCoordinator.Token
+        do {
+            token = try await coordinator.acquire(
+                .playback,
+                onInterrupted: { [weak self] in self?.stop() },
+                onCategoryEscalated: { [weak self] in self?.restartEngine() }
+            )
+        } catch {
+            acquiringSession = false
+            SecureLogger.error("PTT playback session activation failed: \(error)", category: .session)
+            // Playing unregistered would leave the engine exposed: another
+            // holder's last release deactivates the session mid-play, and no
+            // interruption/escalation fan-out ever reaches us. Bail like the
+            // engine-start failure below; the burst still assembles to file.
+            // (stop() also fires onStopped so a parked draining player is
+            // unparked instead of leaking.)
+            stop()
+            return
+        }
+        acquiringSession = false
+        // stop() (cancel, exclusivity, teardown) may have landed while the
+        // session was activating: hand the token straight back.
+        guard !stopped else {
+            coordinator.release(token)
+            return
+        }
+        sessionToken = token
+        guard let playbackReservation,
+              exclusivity.isCurrent(playbackReservation, for: self)
+        else {
+            // The request was superseded while audio-session activation was
+            // suspended. Do not even start the retired engine.
+            stop()
+            return
+        }
+
+        // Observe reconfiguration before starting so nothing lands between.
+        registerConfigObserver()
+        do {
+            try engine.start()
+        } catch {
+            // A capture racing this start can reconfigure the session while
+            // the engine spins up (its escalation fan-out no-ops on a player
+            // that never started): rebuild once against the settled
+            // configuration — counted against the restart cap — before
+            // giving up.
+            SecureLogger.warning("PTT playback engine failed to start (\(error)) — rebuilding once", category: .session)
+            removeConfigObserver()
+            engineRestarts += 1
+            engine = makeEngine()
+            registerConfigObserver()
+            do {
+                try engine.start()
+            } catch {
+                SecureLogger.error("PTT playback engine failed to start: \(error)", category: .session)
+                // stop() removes the observer, hands the token back, and
+                // fires onStopped for any parked draining owner.
+                stop()
+                return
+            }
+        }
+        engineStarted = true
+        guard exclusivity.activate(self, reservation: playbackReservation)
+        else {
+            // A newer user-initiated playback reserved the floor while this
+            // older PTT request was suspended in audio-session activation.
+            // Never let the late completion steal playback back.
+            stop()
+            return
+        }
+        isPlaying = true
+        engine.play()
+
+        let buffered = queuedBuffers
+        queuedBuffers = []
+        queuedDuration = 0
+        for buffer in buffered {
+            schedule(buffer)
+        }
+    }
+
+    /// The audio session was reconfigured underneath the running engine
+    /// (category escalation for talk-over, or an engine configuration
+    /// change): rebuild a fresh engine against the new configuration and
+    /// keep streaming. Buffers already completed stay completed; the
+    /// unfinished scheduled tail is replayed in order on the fresh engine,
+    /// and frames still arriving continue scheduling after it.
+    private func restartEngine() {
+        guard engineStarted, !stopped else { return }
+        engineRestarts += 1
+        guard engineRestarts <= Self.maxEngineRestarts else {
+            SecureLogger.warning("PTT playback: engine reconfigured \(engineRestarts) times in one burst — stopping", category: .session)
+            stop()
+            return
+        }
+
+        removeConfigObserver()
+        // Claim the unfinished tail before stopping the old engine. Stopping
+        // a player node may itself invoke its completion handlers; retiring
+        // the claimed entries first makes those callbacks unambiguously stale.
+        // A completion that fired just before this rebuild wins the latch and
+        // is excluded even if its MainActor task has not run yet.
+        let buffersToReplay = scheduledBuffers.compactMap { scheduled in
+            scheduled.completionState.retireIfPending() ? scheduled.buffer : nil
+        }
+        scheduledBuffers = []
+        engineGeneration += 1
+        engine.stop()
+        engine = makeEngine()
+        registerConfigObserver()
+        do {
+            try engine.start()
+        } catch {
+            SecureLogger.error("PTT playback engine failed to restart after session reconfigure: \(error)", category: .session)
+            stop()
+            return
+        }
+        engine.play()
+        for buffer in buffersToReplay {
+            schedule(buffer)
+        }
+        SecureLogger.info("PTT playback: engine restarted after session reconfigure", category: .session)
+        // If every old buffer completed before the rebuild, a finished burst
+        // can stop now. Otherwise the replayed tail keeps it alive until its
+        // new-generation completions arrive.
+        stopIfDrained()
+    }
+
+    private func registerConfigObserver() {
+        guard let object = engine.configChangeObject else { return }
+        configChangeObserver = NotificationCenter.default.addObserver(
+            forName: .AVAudioEngineConfigurationChange,
+            object: object,
+            queue: .main
+        ) { [weak self] _ in
+            Task { @MainActor [weak self] in
+                self?.restartEngine()
+            }
+        }
+    }
+
+    private func removeConfigObserver() {
+        if let observer = configChangeObserver {
+            NotificationCenter.default.removeObserver(observer)
+            configChangeObserver = nil
+        }
+    }
+
+    private func schedule(_ buffer: AVAudioPCMBuffer) {
+        let id = nextScheduledBufferID
+        nextScheduledBufferID &+= 1
+        let completionState = PTTPlaybackCompletionState()
+        scheduledBuffers.append(ScheduledBuffer(
+            id: id,
+            buffer: buffer,
+            completionState: completionState
+        ))
+        let generation = engineGeneration
+        engine.schedule(buffer, completionType: .dataPlayedBack) { [weak self, completionState] event in
+            guard event == .dataPlayedBack else { return }
+            // Mark completion before hopping to MainActor. A rebuild can then
+            // distinguish already-completed audio from an unfinished tail
+            // even when this task has not run yet.
+            guard completionState.complete() else { return }
+            Task { @MainActor [weak self] in
+                guard let self, self.engineGeneration == generation else { return }
+                self.scheduledBuffers.removeAll { $0.id == id }
+                self.stopIfDrained()
+            }
+        }
+    }
+
+    private func retireScheduledBuffers() {
+        engineGeneration += 1
+        for scheduled in scheduledBuffers {
+            _ = scheduled.completionState.retireIfPending()
+        }
+        scheduledBuffers = []
+    }
+
+    private func stopIfDrained() {
+        guard finished, scheduledBuffers.isEmpty else { return }
+        // Started: everything scheduled has played out. Never started with
+        // nothing queued or in flight (e.g. no decodable frames): nothing
+        // will ever play. Otherwise the engine start is still pending (the
+        // async session acquire) and the queued audio must play out first.
+        guard engineStarted || (!acquiringSession && queuedBuffers.isEmpty) else { return }
+        stop()
+    }
+
+    private func releaseSessionToken() {
+        sessionToken.map(coordinator.release)
+        sessionToken = nil
+    }
+}
+
+extension PTTBurstPlayer: ExclusivePlayback {
+    /// A live stream can't meaningfully pause; yielding the floor stops it.
+    /// The burst keeps assembling to file, so nothing is lost.
+    nonisolated func pauseForExclusivity() {
+        Task { @MainActor [weak self] in
+            self?.stop()
+        }
+    }
+}
@@ -0,0 +1,326 @@
+//
+// PTTCaptureEngine.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import AVFoundation
+import BitLogger
+import Foundation
+
+/// Owns one capture token and returns it even when the capture engine's owner
+/// disappears without reaching its normal stop/cancel path. The coordinator
+/// retains registered tokens strongly, so relying on `Token.deinit` cannot
+/// reclaim an abandoned hold.
+final class PTTCaptureSessionLease: @unchecked Sendable {
+    private let coordinator: AudioSessionCoordinator
+    private let lock = NSLock()
+    private var token: AudioSessionCoordinator.Token?
+
+    init(coordinator: AudioSessionCoordinator) {
+        self.coordinator = coordinator
+    }
+
+    func install(_ token: AudioSessionCoordinator.Token) {
+        let previous = lock.withLock {
+            let previous = self.token
+            self.token = token
+            return previous
+        }
+        previous.map(coordinator.release)
+    }
+
+    func release() {
+        let token = lock.withLock {
+            let token = self.token
+            self.token = nil
+            return token
+        }
+        token.map(coordinator.release)
+    }
+
+    deinit {
+        release()
+    }
+}
+
+/// Monotonic capture identity shared by main-actor lifecycle code and queued
+/// engine callbacks. Removing a notification observer does not cancel a block
+/// already enqueued on the main queue, so every callback must also prove it
+/// still belongs to the current hold before mutating capture state.
+final class PTTCaptureGeneration: @unchecked Sendable {
+    private let lock = NSLock()
+    private var value: UInt = 0
+
+    func begin() -> UInt {
+        lock.withLock {
+            value &+= 1
+            return value
+        }
+    }
+
+    func invalidate() {
+        lock.withLock { value &+= 1 }
+    }
+
+    func invalidate(ifCurrent generation: UInt) -> Bool {
+        lock.withLock {
+            guard value == generation else { return false }
+            value &+= 1
+            return true
+        }
+    }
+
+    func isCurrent(_ generation: UInt) -> Bool {
+        lock.withLock { value == generation }
+    }
+}
+
+/// Captures microphone audio for a live push-to-talk burst, producing both:
+/// - live AAC frames via `onFrames` (called on the capture queue), and
+/// - a finalized `.m4a` voice note on `stop()` — the same artifact
+///   `VoiceRecorder` produces, so the existing voice-note send pipeline
+///   handles delivery to receivers that missed the live stream.
+/// `@unchecked Sendable`: every mutable property is confined to one executor —
+/// the capture `queue` (resampler/encoder/file/counters) or the main actor
+/// (`engine`, `engineStarted`, `sessionLease`, `configChangeObserver`) — so
+/// weak references may cross the `@Sendable` tap/notification closures, which
+/// immediately hop back to the owning executor.
+final class PTTCaptureEngine: @unchecked Sendable {
+    /// Hard cap matching `VoiceRecorder.maxRecordingDuration`: past it the
+    /// engine keeps running (the UI owns the gesture) but stops encoding.
+    private static let maxCaptureDuration: TimeInterval = 120
+
+    /// Recreated on every `start()`: an engine whose input unit was
+    /// instantiated against an earlier (playback-only or inactive) audio
+    /// session keeps reporting a dead 0 Hz / 2 ch input format and fails to
+    /// enable the mic (AURemoteIO -10851, observed on iPhone field tests).
+    private var engine = AVAudioEngine()
+    private let queue = DispatchQueue(label: "chat.bitchat.ptt.capture", qos: .userInitiated)
+    private let coordinator: AudioSessionCoordinator
+    private let sessionLease: PTTCaptureSessionLease
+    private let captureGeneration = PTTCaptureGeneration()
+
+    // Capture-queue-confined state.
+    private var resampler: PTTInputResampler?
+    private var encoder: PTTFrameEncoder?
+    private var file: AVAudioFile?
+    private var fileURL: URL?
+    private var encodedFrameCount = 0
+    private var running = false
+    private var captureStart = Date()
+    /// Whether `engine.start()` succeeded for the current capture
+    /// (see `stopEngineIfStarted`).
+    @MainActor private var engineStarted = false
+    @MainActor private var configChangeObserver: NSObjectProtocol?
+    /// Called on the capture queue with each batch of encoded AAC frames.
+    var onFrames: (([Data]) -> Void)?
+
+    enum CaptureError: Error {
+        case inputUnavailable
+        case audioSetupFailed
+    }
+
+    init(coordinator: AudioSessionCoordinator = .shared) {
+        self.coordinator = coordinator
+        self.sessionLease = PTTCaptureSessionLease(coordinator: coordinator)
+    }
+
+    deinit {
+        sessionLease.release()
+    }
+
+    /// Async because acquiring the session hops its blocking IPC off the main
+    /// actor (a PTT press used to stall main >1 s in `setActive`); the engine
+    /// itself still starts back on main once the session is configured.
+    @MainActor
+    func start(outputURL: URL) async throws {
+        let generation = captureGeneration.begin()
+        let token = try await coordinator.acquire(.capture) { [weak self] in
+            self?.handleInterruption(for: generation)
+        }
+        // The hold ended (stop/cancel) while the session was activating:
+        // starting the engine now would leave a hot mic after release.
+        guard captureGeneration.isCurrent(generation) else {
+            coordinator.release(token)
+            throw CancellationError()
+        }
+        sessionLease.install(token)
+        do {
+            try beginCapture(outputURL: outputURL, generation: generation)
+        } catch {
+            releaseSessionToken()
+            throw error
+        }
+    }
+
+    @MainActor
+    private func beginCapture(outputURL: URL, generation: UInt) throws {
+        // Fresh engine per capture so its input unit binds to the session
+        // that is active *now* (see `engine` doc comment).
+        engine = AVAudioEngine()
+        let inputFormat = engine.inputNode.outputFormat(forBus: 0)
+        guard inputFormat.sampleRate > 0, inputFormat.channelCount > 0 else {
+            SecureLogger.error("PTT: capture input unavailable (input reports \(Int(inputFormat.sampleRate)) Hz, \(inputFormat.channelCount) ch)", category: .session)
+            throw CaptureError.inputUnavailable
+        }
+        guard let resampler = PTTInputResampler(inputFormat: inputFormat),
+              let encoder = PTTFrameEncoder(),
+              let pcmFormat = PTTAudioFormat.pcmFormat
+        else { throw CaptureError.audioSetupFailed }
+
+        let file = try AVAudioFile(
+            forWriting: outputURL,
+            settings: PTTAudioFormat.voiceNoteFileSettings,
+            commonFormat: pcmFormat.commonFormat,
+            interleaved: pcmFormat.isInterleaved
+        )
+
+        queue.sync {
+            self.resampler = resampler
+            self.encoder = encoder
+            self.file = file
+            self.fileURL = outputURL
+            self.encodedFrameCount = 0
+            self.captureStart = Date()
+            self.running = true
+        }
+
+        engine.inputNode.installTap(onBus: 0, bufferSize: 4096, format: inputFormat) { [weak self] buffer, _ in
+            self?.queue.async { self?.process(buffer, generation: generation) }
+        }
+        // Route/category changes reconfigure the engine underneath the tap;
+        // stop and finalize cleanly — the .m4a captured so far still sends.
+        // Registered before start() so no reconfigure lands unobserved
+        // (handleInterruption also validates this capture generation).
+        configChangeObserver = NotificationCenter.default.addObserver(
+            forName: .AVAudioEngineConfigurationChange,
+            object: engine,
+            queue: .main
+        ) { [weak self] _ in
+            Task { @MainActor [weak self] in
+                self?.handleInterruption(for: generation)
+            }
+        }
+        engine.prepare()
+        do {
+            try engine.start()
+        } catch {
+            SecureLogger.error("PTT: capture engine failed to start (input: \(Int(inputFormat.sampleRate)) Hz, \(inputFormat.channelCount) ch): \(error)", category: .session)
+            if let observer = configChangeObserver {
+                NotificationCenter.default.removeObserver(observer)
+                configChangeObserver = nil
+            }
+            engine.inputNode.removeTap(onBus: 0)
+            queue.sync { self.teardown(deleteFile: true) }
+            throw error
+        }
+        engineStarted = true
+        SecureLogger.info("PTT: capture engine running (input: \(Int(inputFormat.sampleRate)) Hz, \(inputFormat.channelCount) ch)", category: .session)
+    }
+
+    /// Stops capture and finalizes the `.m4a`. Returns the file URL and the
+    /// number of encoded AAC frames (each `PTTAudioFormat.frameDuration` long).
+    @MainActor
+    func stop() -> (url: URL?, encodedFrames: Int) {
+        captureGeneration.invalidate()
+        stopEngineIfStarted()
+        let result: (URL?, Int) = queue.sync {
+            let url = fileURL
+            let frames = encodedFrameCount
+            teardown(deleteFile: false)
+            return (url, frames)
+        }
+        releaseSessionToken()
+        return result
+    }
+
+    @MainActor
+    func cancel() {
+        captureGeneration.invalidate()
+        stopEngineIfStarted()
+        queue.sync { teardown(deleteFile: true) }
+        releaseSessionToken()
+    }
+
+    /// Audio session interrupted (call, Siri) or the engine was reconfigured
+    /// mid-capture: behave like `stop()` — finalize the `.m4a` container but
+    /// keep `fileURL`/`encodedFrameCount` so the caller's pending `stop()`
+    /// still returns the note for delivery.
+    @MainActor
+    private func handleInterruption(for generation: UInt) {
+        // Also invalidate a start whose acquire has registered its token but
+        // has not returned to this actor yet. Without this bump the callback
+        // is lost while `engineStarted == false`, and the resumed start can
+        // open the mic after the stop signal.
+        guard captureGeneration.invalidate(ifCurrent: generation) else { return }
+        guard engineStarted else {
+            releaseSessionToken()
+            return
+        }
+        stopEngineIfStarted()
+        queue.sync {
+            running = false
+            // Releasing the AVAudioFile finalizes the .m4a container.
+            file = nil
+            encoder = nil
+            resampler = nil
+        }
+        releaseSessionToken()
+        SecureLogger.info("PTT: capture interrupted — burst finalized early", category: .session)
+    }
+
+    /// Touching `inputNode` on an engine that never started instantiates its
+    /// input unit against whatever session is active and spams AURemoteIO
+    /// errors — a canceled-before-start hold must not touch the engine.
+    @MainActor
+    private func stopEngineIfStarted() {
+        if let observer = configChangeObserver {
+            NotificationCenter.default.removeObserver(observer)
+            configChangeObserver = nil
+        }
+        guard engineStarted else { return }
+        engineStarted = false
+        engine.inputNode.removeTap(onBus: 0)
+        engine.stop()
+    }
+
+    @MainActor
+    private func releaseSessionToken() {
+        sessionLease.release()
+    }
+
+    // MARK: - Capture queue
+
+    private func process(_ buffer: AVAudioPCMBuffer, generation: UInt) {
+        guard captureGeneration.isCurrent(generation),
+              running,
+              Date().timeIntervalSince(captureStart) < Self.maxCaptureDuration,
+              let resampled = resampler?.resample(buffer)
+        else { return }
+
+        do {
+            try file?.write(from: resampled)
+        } catch {
+            SecureLogger.error("PTT capture file write failed: \(error)", category: .session)
+        }
+
+        guard let frames = encoder?.encode(resampled), !frames.isEmpty else { return }
+        encodedFrameCount += frames.count
+        onFrames?(frames)
+    }
+
+    private func teardown(deleteFile: Bool) {
+        running = false
+        // Releasing the AVAudioFile finalizes the .m4a container.
+        file = nil
+        encoder = nil
+        resampler = nil
+        if deleteFile, let url = fileURL {
+            try? FileManager.default.removeItem(at: url)
+        }
+        fileURL = nil
+    }
+}
@@ -0,0 +1,39 @@
+//
+// PTTSettings.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import Foundation
+#if os(iOS)
+import UIKit
+#elseif os(macOS)
+import AppKit
+#endif
+
+/// User preference for live push-to-talk voice. One switch controls both
+/// directions: streaming your holds live, and auto-playing inbound bursts.
+/// Off means voice messages behave exactly like classic voice notes.
+enum PTTSettings {
+    private static let liveVoiceEnabledKey = "ptt.liveVoiceEnabled"
+
+    static var liveVoiceEnabled: Bool {
+        get { UserDefaults.standard.object(forKey: liveVoiceEnabledKey) as? Bool ?? true }
+        set { UserDefaults.standard.set(newValue, forKey: liveVoiceEnabledKey) }
+    }
+
+    /// Autoplay is foreground-only: audio must never start from the
+    /// background.
+    @MainActor
+    static var isAppActive: Bool {
+        #if os(iOS)
+        return UIApplication.shared.applicationState == .active
+        #elseif os(macOS)
+        return NSApplication.shared.isActive
+        #else
+        return true
+        #endif
+    }
+}
@@ -0,0 +1,250 @@
+//
+// VoiceCaptureSession.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import BitFoundation
+import BitLogger
+import Foundation
+
+/// Capture backend behind the composer's hold-to-record gesture.
+/// `VoiceRecordingViewModel` drives one session per press; the concrete type
+/// decides *how* audio leaves the device: `VoiceNoteCaptureSession` records a
+/// note delivered on release (today's behavior), `PTTLiveVoiceSession`
+/// additionally streams frames live while the button is held.
+@MainActor
+protocol VoiceCaptureSession: AnyObject {
+    /// Whether audio is leaving the device in real time while recording —
+    /// drives the composer's LIVE treatment.
+    var isLive: Bool { get }
+    func requestPermission() async -> Bool
+    func start() async throws
+    /// Stops capture and returns the finalized voice-note file, or nil when
+    /// nothing valid was captured.
+    func finish() async -> URL?
+    func cancel() async
+    /// Stops capture and suppresses every later send before returning.
+    func panicCancelSynchronously()
+}
+
+/// The classic record-then-send backend, wrapping the shared `VoiceRecorder`.
+@MainActor
+final class VoiceNoteCaptureSession: VoiceCaptureSession {
+    private let recorder: VoiceRecorder
+    private let owner = VoiceRecorder.RecordingOwner()
+
+    var isLive: Bool { false }
+
+    init(recorder: VoiceRecorder = .shared) {
+        self.recorder = recorder
+    }
+
+    func requestPermission() async -> Bool {
+        await recorder.requestPermission()
+    }
+
+    func start() async throws {
+        try await recorder.startRecording(owner: owner)
+    }
+
+    func finish() async -> URL? {
+        await recorder.stopRecording(owner: owner)
+    }
+
+    func cancel() async {
+        await recorder.cancelRecording(owner: owner)
+    }
+
+    func panicCancelSynchronously() {
+        recorder.panicCancelSynchronously(owner: owner)
+    }
+}
+
+/// Testable surface of the live capture engine. Production uses
+/// `PTTCaptureEngine`; tests can supply captured-frame counts without opening
+/// real audio hardware.
+@MainActor
+protocol PTTCapturing: AnyObject {
+    var onFrames: (([Data]) -> Void)? { get set }
+    func start(outputURL: URL) async throws
+    func stop() -> (url: URL?, encodedFrames: Int)
+    func cancel()
+}
+
+extension PTTCaptureEngine: PTTCapturing {}
+
+/// Live push-to-talk backend: streams `VoiceBurstPacket`s to one peer while
+/// recording, then finalizes the same audio as a standard voice note whose
+/// file name carries the burst ID (`voice_<burstID>.m4a`) so receivers that
+/// heard the live stream absorb the note silently instead of seeing a
+/// duplicate.
+@MainActor
+final class PTTLiveVoiceSession: VoiceCaptureSession {
+    let burstID: Data
+
+    private let sendPacket: (Data) -> Void
+    private let capture: any PTTCapturing
+    private let now: () -> Date
+    /// Capture-queue-confined stream state: packetizes frames and lazily
+    /// emits START so packet order is guaranteed by queue serialization.
+    private final class StreamState {
+        var packetizer: VoiceBurstPacketizer
+        var sentStart = false
+        init(burstID: Data) {
+            packetizer = VoiceBurstPacketizer(burstID: burstID)
+        }
+    }
+    private let stream: StreamState
+    private var startDate: Date?
+    private var completed = false
+
+    var isLive: Bool { true }
+
+    /// - Parameter sendPacket: delivers one encoded `VoiceBurstPacket` to the
+    ///   target peer; must be safe to call from any queue (BLEService hops to
+    ///   its own message queue internally).
+    init(
+        sendPacket: @escaping (Data) -> Void,
+        capture: (any PTTCapturing)? = nil,
+        now: @escaping () -> Date = Date.init,
+        burstID: Data? = nil
+    ) {
+        self.burstID = burstID ?? VoiceBurstPacket.makeBurstID()
+        self.sendPacket = sendPacket
+        self.capture = capture ?? PTTCaptureEngine()
+        self.now = now
+        self.stream = StreamState(burstID: self.burstID)
+    }
+
+    func requestPermission() async -> Bool {
+        await VoiceRecorder.shared.requestPermission()
+    }
+
+    func start() async throws {
+        let outputURL = try Self.makeOutputURL(burstID: burstID)
+        let sendPacket = sendPacket
+        let stream = stream
+        capture.onFrames = { frames in
+            if !stream.sentStart {
+                stream.sentStart = true
+                if let start = VoiceBurstPacket(
+                    burstID: stream.packetizer.burstID,
+                    seq: 0,
+                    kind: .start(codec: .aacLC16kMono)
+                ) {
+                    sendPacket(start.encode())
+                }
+            }
+            for frame in frames {
+                for packet in stream.packetizer.add(frame) {
+                    sendPacket(packet)
+                }
+            }
+            // Flush per callback batch: at ~130-byte frames the budget fits
+            // one frame per packet anyway, and holding residue would add
+            // ~100 ms of avoidable latency.
+            for packet in stream.packetizer.flush() {
+                sendPacket(packet)
+            }
+        }
+        do {
+            try await capture.start(outputURL: outputURL)
+        } catch is CancellationError {
+            // The hold was released/canceled while the session acquire was
+            // in flight: the engine never started and the capture already
+            // handed its token back — nothing to retry. A coordinator-side
+            // interruption during handoff also cancels acquire, but that is
+            // not a successful start and must propagate to the view model.
+            guard completed else { throw CancellationError() }
+            return
+        } catch {
+            // The HAL can briefly report a dead input right after the audio
+            // session (re)activates while the route settles; one retry after
+            // a short pause covers it (observed on iPhone field tests).
+            SecureLogger.warning("PTT: capture start failed (\(error)) — retrying once after route settle", category: .session)
+            try? await Task.sleep(nanoseconds: 150_000_000)
+            // The hold may have been released/canceled during the retry pause.
+            // Starting the mic now would leave it live and streaming after the
+            // user let go, so bail instead of opening a hot mic.
+            guard !completed else {
+                capture.cancel()
+                return
+            }
+            try await capture.start(outputURL: outputURL)
+        }
+        startDate = now()
+        SecureLogger.info("PTT: live burst \(burstID.hexEncodedString()) capture started", category: .session)
+    }
+
+    func finish() async -> URL? {
+        guard !completed else { return nil }
+        completed = true
+
+        let elapsed = startDate.map { now().timeIntervalSince($0) } ?? 0
+        let (url, encodedFrames) = capture.stop()
+        // stop() drained the capture queue, so touching `stream` is safe now.
+
+        let capturedDuration = Double(encodedFrames) * PTTAudioFormat.frameDuration
+
+        guard elapsed >= VoiceRecorder.minRecordingDuration,
+              capturedDuration >= VoiceRecorder.minRecordingDuration,
+              let url
+        else {
+            sendControlPacket(.canceled)
+            if let url {
+                try? FileManager.default.removeItem(at: url)
+            }
+            return nil
+        }
+
+        for packet in stream.packetizer.flush() {
+            sendPacket(packet)
+        }
+        let durationMs = UInt32((capturedDuration * 1000).rounded())
+        sendControlPacket(.end(totalDataPackets: stream.packetizer.dataPacketCount, durationMs: durationMs))
+        SecureLogger.info("PTT: live burst \(burstID.hexEncodedString()) finished — \(stream.packetizer.dataPacketCount) data packets, \(encodedFrames) frames, \(durationMs) ms", category: .session)
+        return url
+    }
+
+    func cancel() async {
+        let alreadyCompleted = completed
+        completed = true
+        // Always tear down the capture, even if a quick-release already marked
+        // us completed: the engine can start late (during start()'s retry
+        // pause), and only capture.cancel() stops the mic and deactivates the
+        // session. It is idempotent, so a redundant call is harmless.
+        capture.cancel()
+        if !alreadyCompleted {
+            sendControlPacket(.canceled)
+        }
+    }
+
+    func panicCancelSynchronously() {
+        // Do not emit a canceled packet: it would itself be pre-panic
+        // conversation data racing the emergency transport reset.
+        completed = true
+        capture.cancel()
+    }
+
+    private func sendControlPacket(_ kind: VoiceBurstPacket.Kind) {
+        guard let packet = VoiceBurstPacket(burstID: burstID, seq: stream.packetizer.nextSeq, kind: kind) else { return }
+        sendPacket(packet.encode())
+    }
+
+    private static func makeOutputURL(burstID: Data) throws -> URL {
+        let base = try FileManager.default.url(
+            for: .applicationSupportDirectory,
+            in: .userDomainMask,
+            appropriateFor: nil,
+            create: true
+        )
+        let directory = base
+            .appendingPathComponent("files", isDirectory: true)
+            .appendingPathComponent("voicenotes/outgoing", isDirectory: true)
+        try FileManager.default.createDirectory(at: directory, withIntermediateDirectories: true, attributes: nil)
+        return directory.appendingPathComponent("voice_\(burstID.hexEncodedString()).m4a")
+    }
+}
@@ -9,6 +9,9 @@ final class VoiceNotePlaybackController: NSObject, ObservableObject, AVAudioPlay
    @Published private(set) var duration: TimeInterval = 0
    @Published private(set) var progress: Double = 0

+    /// Internal lifecycle visibility for deterministic acquisition tests.
+    var isPlaybackStartPending: Bool { sessionAcquireInFlight }
+
    /// rounded so 4.9s shows "00:05"
    var roundedDuration: Int {
        guard duration.isFinite else { return 0 }
@@ -24,9 +27,24 @@ final class VoiceNotePlaybackController: NSObject, ObservableObject, AVAudioPlay
    private var player: AVAudioPlayer?
    private var timer: Timer?
    private var url: URL
+    /// Test seam; `AudioSessionCoordinator.shared` when nil.
+    private let sessionCoordinatorOverride: AudioSessionCoordinator?
+    /// Injectable so tests don't fight over the app-wide exclusive-playback
+    /// slot (a parallel test's `play()` would pause this controller mid-test).
+    private let exclusivity: VoiceNotePlaybackCoordinator
+    private var sessionToken: AudioSessionCoordinator.Token?
+    /// A session acquire is in flight (it suspends off-main for the blocking
+    /// session IPC); gates against double acquisition on rapid play taps.
+    private var sessionAcquireInFlight = false

-    init(url: URL) {
+    init(
+        url: URL,
+        sessionCoordinator: AudioSessionCoordinator? = nil,
+        exclusivity: VoiceNotePlaybackCoordinator? = nil
+    ) {
        self.url = url
+        self.sessionCoordinatorOverride = sessionCoordinator
+        self.exclusivity = exclusivity ?? .shared
        super.init()
        // Don't load anything eagerly - wait until user interaction or view is fully displayed
    }
@@ -51,6 +69,16 @@ final class VoiceNotePlaybackController: NSObject, ObservableObject, AVAudioPlay

    deinit {
        timer?.invalidate()
+        player?.stop()
+        // A per-row @StateObject can be discarded mid-playback (navigating
+        // away). Leaking the token here would hold the session forever —
+        // never deactivating it, and pinning any escalated category for the
+        // app's lifetime. `release` is fire-and-forget onto the coordinator's
+        // queue, so it is deinit-safe: only the Sendable token crosses.
+        if let token = sessionToken {
+            sessionToken = nil
+            (sessionCoordinatorOverride ?? .shared).release(token)
+        }
    }

    func replaceURL(_ url: URL) {
@@ -68,11 +96,15 @@ final class VoiceNotePlaybackController: NSObject, ObservableObject, AVAudioPlay

    func play() {
        guard ensurePlayerReady() else { return }
-        VoiceNotePlaybackCoordinator.shared.activate(self)
-        player?.play()
+        exclusivity.activate(self)
+        isPlaying = true
        startTimer()
        updateProgress()
-        isPlaying = true
+        // Acquired here (not in ensurePlayerReady): scrubbing a paused note
+        // must not hold the session while nothing is audible. The session
+        // calls block on audio-server IPC, so they run off the main thread;
+        // the player starts once the session is configured.
+        startPlayerAfterAcquiringSession()
    }

    func pause() {
@@ -80,6 +112,7 @@ final class VoiceNotePlaybackController: NSObject, ObservableObject, AVAudioPlay
        stopTimer()
        updateProgress()
        isPlaying = false
+        releaseSession()
    }

    func stop() {
@@ -88,7 +121,8 @@ final class VoiceNotePlaybackController: NSObject, ObservableObject, AVAudioPlay
        stopTimer()
        updateProgress()
        isPlaying = false
-        VoiceNotePlaybackCoordinator.shared.deactivate(self)
+        releaseSession()
+        exclusivity.deactivate(self)
    }

    func seek(to fraction: Double) {
@@ -96,8 +130,11 @@ final class VoiceNotePlaybackController: NSObject, ObservableObject, AVAudioPlay
        let clamped = max(0, min(1, fraction))
        if let player = player {
            player.currentTime = clamped * player.duration
-            if isPlaying {
-                player.play()
+            // While the session acquire is still in flight, don't start
+            // audio pre-activation — the pending acquire's completion starts
+            // playback (from the new position) once the session resolves.
+            if isPlaying, !sessionAcquireInFlight {
+                startPreparedPlayer()
            }
            updateProgress()
        }
@@ -112,18 +149,20 @@ final class VoiceNotePlaybackController: NSObject, ObservableObject, AVAudioPlay
            self.stopTimer()
            self.updateProgress()
            self.isPlaying = false
-            VoiceNotePlaybackCoordinator.shared.deactivate(self)
+            self.releaseSession()
+            self.exclusivity.deactivate(self)
        }
    }

    // MARK: - Private Helpers

    private func preparePlayer(for url: URL) {
-        // Prepare player synchronously (only called when playback is requested)
+        // Load metadata synchronously, but do not call prepareToPlay here:
+        // paused scrubbing reaches this path and must not acquire playback
+        // hardware outside the AudioSessionCoordinator token lifetime.
        do {
            let player = try AVAudioPlayer(contentsOf: url)
            player.delegate = self
-            player.prepareToPlay()
            self.player = player
            duration = player.duration
            currentTime = player.currentTime
@@ -141,16 +180,79 @@ final class VoiceNotePlaybackController: NSObject, ObservableObject, AVAudioPlay
        if player == nil {
            preparePlayer(for: url)
        }
-        #if os(iOS)
-        let session = AVAudioSession.sharedInstance()
+        return player != nil
+    }
+
+    /// All entry points (SwiftUI actions, `pauseForExclusivity`, the
+    /// delegate's main-queue hop) run on the main thread; the acquire itself
+    /// suspends while the blocking session IPC runs on the coordinator's
+    /// queue, and the player starts when it resolves. An acquire failure
+    /// leaves playback stopped: starting without a registered token would
+    /// bypass interruption fan-out and the coordinator's refcount. A
+    /// pause/stop landing mid-acquire hands the token straight back.
+    private func startPlayerAfterAcquiringSession() {
+        if sessionToken != nil {
+            startPreparedPlayer()
+            return
+        }
+        guard !sessionAcquireInFlight else { return }
+        sessionAcquireInFlight = true
+        let coordinator = sessionCoordinatorOverride ?? AudioSessionCoordinator.shared
+        Task { @MainActor [weak self] in
+            var token: AudioSessionCoordinator.Token?
            do {
-            try session.setCategory(.playback, mode: .spokenAudio, options: [.mixWithOthers])
-            try session.setActive(true, options: [])
+                token = try await coordinator.acquire(.playback) { [weak self] in
+                    self?.pause()
+                }
            } catch {
                SecureLogger.error("Failed to activate audio session: \(error)", category: .session)
            }
-        #endif
-        return player != nil
+            guard let self else {
+                // The row was discarded while acquiring; deinit had no token
+                // to release yet.
+                token.map(coordinator.release)
+                return
+            }
+            self.sessionAcquireInFlight = false
+            guard self.isPlaying else {
+                // Paused/stopped while the session was activating.
+                token.map(coordinator.release)
+                return
+            }
+            guard let token else {
+                self.failPlaybackStart()
+                return
+            }
+            self.sessionToken = token
+            self.startPreparedPlayer()
+        }
+    }
+
+    @discardableResult
+    private func startPreparedPlayer() -> Bool {
+        guard let player,
+              player.prepareToPlay(),
+              player.play()
+        else {
+            SecureLogger.error("Voice note player refused to start " + url.lastPathComponent, category: .session)
+            failPlaybackStart()
+            return false
+        }
+        return true
+    }
+
+    private func failPlaybackStart() {
+        player?.pause()
+        stopTimer()
+        updateProgress()
+        isPlaying = false
+        releaseSession()
+        exclusivity.deactivate(self)
+    }
+
+    private func releaseSession() {
+        sessionToken.map((sessionCoordinatorOverride ?? .shared).release)
+        sessionToken = nil
    }

    private func startTimer() {
@@ -181,25 +283,75 @@ final class VoiceNotePlaybackController: NSObject, ObservableObject, AVAudioPlay
    }
 }

-/// Ensures only one voice note plays at a time.
+/// Something that can hold the app's single audio-playback slot and yield it
+/// when another playback starts (voice notes pause; live bursts stop).
+protocol ExclusivePlayback: AnyObject {
+    func pauseForExclusivity()
+}
+
+extension VoiceNotePlaybackController: ExclusivePlayback {
+    func pauseForExclusivity() {
+        pause()
+    }
+}
+
+/// Ensures only one voice playback (note or live burst) runs at a time.
 final class VoiceNotePlaybackCoordinator {
    static let shared = VoiceNotePlaybackCoordinator()

-    private weak var activeController: VoiceNotePlaybackController?
+    struct Reservation: Equatable {
+        fileprivate let generation: UInt64
+    }

-    private init() {}
+    private weak var activeController: (any ExclusivePlayback)?
+    private weak var latestReservedController: (any ExclusivePlayback)?
+    private var latestReservation = Reservation(generation: 0)

-    func activate(_ controller: VoiceNotePlaybackController) {
+    /// Internal so tests can isolate their own exclusivity slot; the app
+    /// uses `shared`.
+    init() {}
+
+    /// Records playback intent without interrupting audio that is already
+    /// audible. Async starters reserve before suspension, then activate only
+    /// after their audio resource is ready.
+    func reserve(_ controller: any ExclusivePlayback) -> Reservation {
+        latestReservation = Reservation(generation: latestReservation.generation &+ 1)
+        latestReservedController = controller
+        return latestReservation
+    }
+
+    /// Immediate activation for synchronous/user-initiated playback.
+    @discardableResult
+    func activate(_ controller: any ExclusivePlayback) -> Reservation {
+        let reservation = reserve(controller)
+        _ = activate(controller, reservation: reservation)
+        return reservation
+    }
+
+    /// Commits an earlier reservation only when it is still the newest
+    /// playback request. This prevents an older async acquire from stealing
+    /// the floor after a newer play gesture.
+    @discardableResult
+    func activate(_ controller: any ExclusivePlayback, reservation: Reservation) -> Bool {
+        guard isCurrent(reservation, for: controller) else { return false }
        if activeController === controller {
-            return
+            return true
        }
-        activeController?.pause()
+        activeController?.pauseForExclusivity()
        activeController = controller
+        return true
    }

-    func deactivate(_ controller: VoiceNotePlaybackController) {
+    func isCurrent(_ reservation: Reservation, for controller: any ExclusivePlayback) -> Bool {
+        latestReservation == reservation && latestReservedController === controller
+    }
+
+    func deactivate(_ controller: any ExclusivePlayback) {
        if activeController === controller {
            activeController = nil
        }
+        if latestReservedController === controller {
+            latestReservedController = nil
+        }
    }
 }
@@ -1,22 +1,95 @@
 import Foundation
 import AVFoundation

+/// The small surface of `AVAudioRecorder` that `VoiceRecorder` owns. Keeping
+/// it behind a protocol lets lifecycle races be tested without opening the
+/// microphone on the test host.
+protocol VoiceAudioRecording: AnyObject {
+    var isRecording: Bool { get }
+    var isMeteringEnabled: Bool { get set }
+    func prepareToRecord() -> Bool
+    func record(forDuration duration: TimeInterval) -> Bool
+    func stop()
+}
+
+extension AVAudioRecorder: VoiceAudioRecording {}
+
+protocol VoiceAudioRecorderCreating {
+    func makeRecorder(url: URL) throws -> any VoiceAudioRecording
+}
+
+private struct SystemVoiceAudioRecorderFactory: VoiceAudioRecorderCreating {
+    func makeRecorder(url: URL) throws -> any VoiceAudioRecording {
+        let settings: [String: Any] = [
+            AVFormatIDKey: kAudioFormatMPEG4AAC,
+            AVSampleRateKey: 16_000,
+            AVNumberOfChannelsKey: 1,
+            AVEncoderBitRateKey: 16_000
+        ]
+        return try AVAudioRecorder(url: url, settings: settings)
+    }
+}
+
 /// Manages audio capture for mesh voice notes with predictable encoding settings.
 actor VoiceRecorder {
-    enum RecorderError: Error {
+    enum RecorderError: Error, Equatable {
        case microphoneAccessDenied
-        case recorderInitializationFailed
        case recordingInProgress
+        case failedToStartRecording
    }

    static let shared = VoiceRecorder()

-    private let paddingInterval: TimeInterval = 0.5
-    private let maxRecordingDuration: TimeInterval = 120
    static let minRecordingDuration: TimeInterval = 1

-    private var recorder: AVAudioRecorder?
+    /// Identity of one press/hold. Every lifecycle mutation must present the
+    /// same owner that started the recorder, so a stale finish or cancel from
+    /// another hold cannot stop or delete the current recording.
+    final class RecordingOwner: @unchecked Sendable {}
+
+    /// Test-only scheduling seams for lifecycle boundaries that otherwise rely
+    /// on wall-clock sleeps. Production uses the real padding delay.
+    struct TestingHooks: Sendable {
+        let waitForStopPadding: (@Sendable (TimeInterval) async -> Void)?
+
+        init(waitForStopPadding: (@Sendable (TimeInterval) async -> Void)? = nil) {
+            self.waitForStopPadding = waitForStopPadding
+        }
+    }
+
+    private let sessionCoordinator: AudioSessionCoordinator
+    private let recorderFactory: any VoiceAudioRecorderCreating
+    private let permissionGranted: () -> Bool
+    private let paddingInterval: TimeInterval
+    private let maxRecordingDuration: TimeInterval
+    private let outputDirectory: URL?
+    private let testingHooks: TestingHooks
+
+    private var recorder: (any VoiceAudioRecording)?
    private var currentURL: URL?
+    private var sessionToken: AudioSessionCoordinator.Token?
+    private var activeOwner: RecordingOwner?
+    /// True only while `startRecording()` is suspended in session acquire.
+    /// A second start is rejected instead of superseding the first one.
+    private var startInFlight = false
+
+    init(
+        sessionCoordinator: AudioSessionCoordinator = .shared,
+        recorderFactory: any VoiceAudioRecorderCreating = SystemVoiceAudioRecorderFactory(),
+        permissionGranted: (() -> Bool)? = nil,
+        paddingInterval: TimeInterval = 0.5,
+        maxRecordingDuration: TimeInterval = 120,
+        outputDirectory: URL? = nil,
+        testingHooks: TestingHooks = TestingHooks()
+    ) {
+        self.sessionCoordinator = sessionCoordinator
+        self.recorderFactory = recorderFactory
+        self.permissionGranted = permissionGranted ?? Self.hasSystemPermission
+        self.paddingInterval = paddingInterval
+        self.maxRecordingDuration = maxRecordingDuration
+        self.outputDirectory = outputDirectory
+        self.testingHooks = testingHooks
+    }

    // MARK: - Permissions

@@ -42,82 +115,130 @@ actor VoiceRecorder {
    // MARK: - Recording Lifecycle

    @discardableResult
-    func startRecording() throws -> URL {
-        if recorder?.isRecording == true {
+    func startRecording(owner: RecordingOwner) async throws -> URL {
+        if activeOwner != nil {
            throw RecorderError.recordingInProgress
        }

-        #if os(iOS)
-        let session = AVAudioSession.sharedInstance()
-        guard session.recordPermission == .granted else {
+        guard permissionGranted() else {
            throw RecorderError.microphoneAccessDenied
        }
-        #if targetEnvironment(simulator)
-        // allowBluetoothHFP is not available on iOS Simulator
-        try session.setCategory(
-            .playAndRecord,
-            mode: .default,
-            options: [.defaultToSpeaker, .allowBluetoothA2DP]
-        )
-        #else
-        try session.setCategory(
-            .playAndRecord,
-            mode: .default,
-            options: [.defaultToSpeaker, .allowBluetoothA2DP, .allowBluetoothHFP]
-        )
-        #endif
-        try session.setActive(true, options: .notifyOthersOnDeactivation)
-        #endif
-        #if os(macOS)
-        guard AVCaptureDevice.authorizationStatus(for: .audio) == .authorized else {
-            throw RecorderError.microphoneAccessDenied
+
+        activeOwner = owner
+        startInFlight = true
+
+        // The acquire suspends while the blocking session IPC runs on the
+        // coordinator's queue (never this actor's thread or main).
+        let token: AudioSessionCoordinator.Token
+        do {
+            token = try await sessionCoordinator.acquire(.capture) { [weak self] in
+                Task { await self?.handleSessionInterruption(for: owner) }
+            }
+        } catch {
+            guard activeOwner === owner else {
+                throw CancellationError()
+            }
+            startInFlight = false
+            activeOwner = nil
+            throw error
        }
-        #endif

-        let outputURL = try makeOutputURL()
-        let settings: [String: Any] = [
-            AVFormatIDKey: kAudioFormatMPEG4AAC,
-            AVSampleRateKey: 16_000,
-            AVNumberOfChannelsKey: 1,
-            AVEncoderBitRateKey: 16_000
-        ]
+        // Actor reentrancy: release/cancel may have ended this hold while the
+        // blocking session activation was still in progress.
+        guard activeOwner === owner, startInFlight else {
+            sessionCoordinator.release(token)
+            throw CancellationError()
+        }
+        startInFlight = false
+        sessionToken = token

-        let audioRecorder = try AVAudioRecorder(url: outputURL, settings: settings)
+        var outputURL: URL?
+        do {
+            let newURL = try makeOutputURL()
+            outputURL = newURL
+            let audioRecorder = try recorderFactory.makeRecorder(url: newURL)
            audioRecorder.isMeteringEnabled = true
-        audioRecorder.prepareToRecord()
-        audioRecorder.record(forDuration: maxRecordingDuration)
+            guard audioRecorder.prepareToRecord() else {
+                throw RecorderError.failedToStartRecording
+            }
+            guard audioRecorder.record(forDuration: maxRecordingDuration) else {
+                throw RecorderError.failedToStartRecording
+            }

            recorder = audioRecorder
-        currentURL = outputURL
-        return outputURL
+            currentURL = newURL
+            return newURL
+        } catch {
+            releaseSessionToken()
+            recorder = nil
+            currentURL = nil
+            activeOwner = nil
+            if let outputURL {
+                try? FileManager.default.removeItem(at: outputURL)
+            }
+            throw error
+        }
    }

-    func stopRecording() async -> URL? {
-        guard let recorder, recorder.isRecording else {
-            return currentURL
+    func stopRecording(owner: RecordingOwner) async -> URL? {
+        guard activeOwner === owner else { return nil }
+
+        // `finish()` can race a still-suspended start on a direct caller even
+        // though the UI normally routes quick releases through cancel().
+        if startInFlight {
+            activeOwner = nil
+            startInFlight = false
+            return nil
+        }
+
+        guard let activeRecorder = recorder else {
+            let sessionURL = currentURL
+            releaseSessionToken()
+            currentURL = nil
+            activeOwner = nil
+            return sessionURL
        }

        let sessionURL = currentURL

+        if activeRecorder.isRecording, paddingInterval > 0 {
+            if let waitForStopPadding = testingHooks.waitForStopPadding {
+                await waitForStopPadding(paddingInterval)
+            } else {
                try? await Task.sleep(nanoseconds: UInt64(paddingInterval * 1_000_000_000))
+            }
+        }

-        recorder.stop()
+        // Cancellation or interruption may have run during the padding sleep.
+        // Only the recorder whose stop began here may be finalized by it.
+        guard activeOwner === owner,
+              let recorder = self.recorder,
+              recorder === activeRecorder
+        else { return nil }

-        // A new session may have started during the sleep — don't touch its state
-        if self.recorder === recorder {
-            cleanupSession()
+        if activeRecorder.isRecording {
+            activeRecorder.stop()
+        }
+        releaseSessionToken()
        self.recorder = nil
        currentURL = nil
-        }
+        activeOwner = nil

        return sessionURL
    }

-    func cancelRecording() {
+    func cancelRecording(owner: RecordingOwner) async {
+        guard activeOwner === owner else { return }
+
+        // Invalidate ownership before cleanup. An actor-reentrant start whose
+        // session acquire resumes later will observe the mismatch and release
+        // its token without opening the microphone.
+        activeOwner = nil
+        startInFlight = false
        if let recorder, recorder.isRecording {
            recorder.stop()
        }
-        cleanupSession()
+        releaseSessionToken()
        if let currentURL {
            try? FileManager.default.removeItem(at: currentURL)
        }
@@ -125,14 +246,60 @@ actor VoiceRecorder {
        currentURL = nil
    }

+    /// Panic is a synchronous security boundary: the caller must know the
+    /// microphone, audio-session lease, and partial file are gone before it
+    /// rotates identities or deletes the media tree. VoiceRecorder is an
+    /// independent actor and this cleanup path never hops to MainActor, so a
+    /// short semaphore join is safe even when invoked by the UI actor.
+    nonisolated
+    func panicCancelSynchronously(owner: RecordingOwner) {
+        let finished = DispatchSemaphore(value: 0)
+        Task {
+            await cancelRecording(owner: owner)
+            finished.signal()
+        }
+        finished.wait()
+    }
+
+    /// The audio session was interrupted (call, Siri) or reconfigured: stop
+    /// the recorder but keep `recorder`/`currentURL` so the caller's pending
+    /// `stopRecording()` still returns the partial note.
+    private func handleSessionInterruption(for owner: RecordingOwner) async {
+        // A callback captured for a released token must never stop a newer
+        // recording. Conversely, an interruption delivered while acquire is
+        // still suspended invalidates that acquire before it can open the mic.
+        guard activeOwner === owner else { return }
+        if startInFlight {
+            activeOwner = nil
+            startInFlight = false
+            return
+        }
+        startInFlight = false
+        if let recorder, recorder.isRecording {
+            recorder.stop()
+        }
+        releaseSessionToken()
+    }
+
    // MARK: - Helpers

+    private static func hasSystemPermission() -> Bool {
+        #if os(iOS)
+        AVAudioSession.sharedInstance().recordPermission == .granted
+        #elseif os(macOS)
+        AVCaptureDevice.authorizationStatus(for: .audio) == .authorized
+        #else
+        true
+        #endif
+    }
+
    private func makeOutputURL() throws -> URL {
        let formatter = DateFormatter()
        formatter.dateFormat = "yyyyMMdd_HHmmss"
-        let fileName = "voice_\(formatter.string(from: Date())).m4a"
+        let fileName = "voice_\(formatter.string(from: Date()))_\(UUID().uuidString).m4a"

-        let baseDirectory = try applicationFilesDirectory().appendingPathComponent("voicenotes/outgoing", isDirectory: true)
+        let baseDirectory = try outputDirectory
+            ?? applicationFilesDirectory().appendingPathComponent("voicenotes/outgoing", isDirectory: true)
        try FileManager.default.createDirectory(at: baseDirectory, withIntermediateDirectories: true, attributes: nil)
        return baseDirectory.appendingPathComponent(fileName)
    }
@@ -147,9 +314,11 @@ actor VoiceRecorder {
        #endif
    }

-    private func cleanupSession() {
-        #if os(iOS)
-        try? AVAudioSession.sharedInstance().setActive(false, options: .notifyOthersOnDeactivation)
-        #endif
+    /// Fire-and-forget: the coordinator hops the blocking deactivation IPC
+    /// onto its own queue.
+    private func releaseSessionToken() {
+        guard let token = sessionToken else { return }
+        sessionToken = nil
+        sessionCoordinator.release(token)
    }
 }
@@ -56,12 +56,6 @@ final class WaveformCache {
        }
    }

-    func purgeAll() {
-        queue.async(flags: .barrier) { [weak self] in
-            self?.cache.removeAll()
-        }
-    }
-
    private func computeWaveform(url: URL, bins: Int) -> [Float]? {
        guard bins > 0 else { return nil }
        // Use autoreleasepool to manage memory from audio buffer allocations
@@ -88,8 +88,6 @@ import BitFoundation
 /// Represents the ephemeral layer of identity - short-lived peer IDs that provide network privacy.
 /// These IDs rotate periodically to prevent tracking while maintaining cryptographic relationships.
 struct EphemeralIdentity {
-    let peerID: PeerID          // 8 random bytes
-    let sessionStart: Date
    var handshakeState: HandshakeState
 }

@@ -98,7 +96,6 @@ enum HandshakeState {
    case initiated
    case inProgress
    case completed(fingerprint: String)
-    case failed(reason: String)
 }

 /// Represents the cryptographic layer of identity - the stable Noise Protocol static key pair.
@@ -110,7 +107,6 @@ struct CryptographicIdentity: Codable {
    // Optional Ed25519 signing public key (used to authenticate public messages)
    var signingPublicKey: Data? = nil
    let firstSeen: Date
-    let lastHandshake: Date?
 }

 /// Represents the social layer of identity - user-assigned names and trust relationships.
@@ -194,8 +190,17 @@ struct IdentityCache: Codable {
    // entries verified before this field exists sort as oldest)
    var verifiedAt: [String: Date]? = nil

-    // Schema version for future migrations
-    var version: Int = 1
+    // Stable Noise fingerprints that proved encrypted private-media support
+    // inside an authenticated Noise session. Optional for decoding caches
+    // written before this migration. Entries are monotonic until a panic wipe
+    // so an old/replayed announce cannot silently downgrade a peer.
+    var privateMediaCapableFingerprints: Set<String>? = nil
+
+    // Noise-fingerprint -> Ed25519 announcement key, learned only from the
+    // authenticated peer-state payload. This prevents a self-signed announce
+    // containing a copied public Noise key from replacing a previously bound
+    // public-message signing identity. Optional for old cache compatibility.
+    var authenticatedSigningKeysByFingerprint: [String: Data]? = nil
 }

 //
@@ -108,8 +108,6 @@ protocol SecureIdentityStateManagerProtocol {
    func updateSocialIdentity(_ identity: SocialIdentity)
    
    // MARK: Favorites Management
-    func getFavorites() -> Set<String>
-    func setFavorite(_ fingerprint: String, isFavorite: Bool)
    func isFavorite(fingerprint: String) -> Bool
    
    // MARK: Blocked Users Management
@@ -123,7 +121,6 @@ protocol SecureIdentityStateManagerProtocol {
    
    // MARK: Ephemeral Session Management
    func registerEphemeralSession(peerID: PeerID, handshakeState: HandshakeState)
-    func updateHandshakeState(peerID: PeerID, state: HandshakeState)

    // MARK: Cleanup
    func clearAllIdentityData()
@@ -139,11 +136,18 @@ protocol SecureIdentityStateManagerProtocol {
    func recordVouch(voucheeFingerprint: String, voucherFingerprint: String, timestamp: Date) -> Bool
    func validVouchers(for fingerprint: String) -> [VouchRecord]
    func isVouched(fingerprint: String) -> Bool
-    func effectiveTrustLevel(for fingerprint: String) -> TrustLevel
    func lastVouchBatchSent(to fingerprint: String) -> Date?
    func markVouchBatchSent(to fingerprint: String, at date: Date)
    func signingPublicKey(forFingerprint fingerprint: String) -> Data?
    func mostRecentlyVerifiedFingerprints(limit: Int, excluding fingerprint: String) -> [String]
+
+    // MARK: Noise-authenticated announcement identity
+    func bindAuthenticatedSigningPublicKey(_ signingPublicKey: Data, fingerprint: String)
+    func authenticatedSigningPublicKey(forFingerprint fingerprint: String) -> Data?
+
+    // MARK: Private-media downgrade protection
+    func markPrivateMediaCapable(fingerprint: String)
+    func hasObservedPrivateMediaCapability(fingerprint: String) -> Bool
 }

 /// Singleton manager for secure identity state persistence and retrieval.
@@ -161,6 +165,7 @@ final class SecureIdentityStateManager: SecureIdentityStateManagerProtocol {
    
    // Thread safety
    private let queue = DispatchQueue(label: "bitchat.identity.state", attributes: .concurrent)
+    private let queueSpecificKey = DispatchSpecificKey<UInt8>()
    
    // Pending-save coalescing flag. Reads/writes are serialized on `queue`.
    // Persistence is done with a fire-and-forget `queue.async(.barrier)` rather
@@ -218,6 +223,7 @@ final class SecureIdentityStateManager: SecureIdentityStateManagerProtocol {

        self.encryptionKey = loadedKey
        self.encryptionKeyIsEphemeral = keyIsEphemeral
+        queue.setSpecific(key: queueSpecificKey, value: 1)

        // Only read the persisted cache when we hold the real key; with an
        // ephemeral key the decrypt would fail and discard the real cache.
@@ -322,21 +328,13 @@ final class SecureIdentityStateManager: SecureIdentityStateManagerProtocol {
                        fingerprint: fingerprint,
                        publicKey: noisePublicKey,
                        signingPublicKey: signingPublicKey ?? existing.signingPublicKey,
-                        firstSeen: existing.firstSeen,
-                        lastHandshake: now
+                        firstSeen: existing.firstSeen
                    )
                    self.cryptographicIdentities[fingerprint] = existing
                } else {
-                    // Update signing key and lastHandshake
+                    // Update signing key
                    existing.signingPublicKey = signingPublicKey ?? existing.signingPublicKey
-                    let updated = CryptographicIdentity(
-                        fingerprint: existing.fingerprint,
-                        publicKey: existing.publicKey,
-                        signingPublicKey: existing.signingPublicKey,
-                        firstSeen: existing.firstSeen,
-                        lastHandshake: now
-                    )
-                    self.cryptographicIdentities[fingerprint] = updated
+                    self.cryptographicIdentities[fingerprint] = existing
                }
                // Persist updated state (already assigned in branches above)
            } else {
@@ -345,8 +343,7 @@ final class SecureIdentityStateManager: SecureIdentityStateManagerProtocol {
                    fingerprint: fingerprint,
                    publicKey: noisePublicKey,
                    signingPublicKey: signingPublicKey,
-                    firstSeen: now,
-                    lastHandshake: now
+                    firstSeen: now
                )
                self.cryptographicIdentities[fingerprint] = entry
            }
@@ -384,6 +381,66 @@ final class SecureIdentityStateManager: SecureIdentityStateManagerProtocol {
        }
    }

+    // MARK: - Private-media downgrade protection
+
+    func markPrivateMediaCapable(fingerprint: String) {
+        guard !fingerprint.isEmpty else { return }
+        let insertAndPersist = {
+            var pinned = self.cache.privateMediaCapableFingerprints ?? []
+            guard pinned.insert(fingerprint).inserted else { return }
+            self.cache.privateMediaCapableFingerprints = pinned
+            self.saveIdentityCache()
+        }
+        // Downgrade decisions can run immediately after an authenticated
+        // announce. Make the pin visible before returning; merely enqueueing a
+        // barrier leaves a cross-queue window where a replay can look legacy.
+        // The queue-specific fast path prevents self-deadlock if a future
+        // identity-state mutation records the capability from inside `queue`.
+        if DispatchQueue.getSpecific(key: queueSpecificKey) != nil {
+            insertAndPersist()
+        } else {
+            queue.sync(flags: .barrier, execute: insertAndPersist)
+        }
+    }
+
+    func hasObservedPrivateMediaCapability(fingerprint: String) -> Bool {
+        guard !fingerprint.isEmpty else { return false }
+        return queue.sync {
+            cache.privateMediaCapableFingerprints?.contains(fingerprint) == true
+        }
+    }
+
+    // MARK: - Noise-authenticated announcement identity
+
+    func bindAuthenticatedSigningPublicKey(_ signingPublicKey: Data, fingerprint: String) {
+        guard signingPublicKey.count == AuthenticatedPeerStatePacket.signingPublicKeyLength,
+              !fingerprint.isEmpty else { return }
+        let bindAndPersist = {
+            var bindings = self.cache.authenticatedSigningKeysByFingerprint ?? [:]
+            let bindingChanged = bindings[fingerprint] != signingPublicKey
+            bindings[fingerprint] = signingPublicKey
+            self.cache.authenticatedSigningKeysByFingerprint = bindings
+            if var cryptoIdentity = self.cryptographicIdentities[fingerprint] {
+                cryptoIdentity.signingPublicKey = signingPublicKey
+                self.cryptographicIdentities[fingerprint] = cryptoIdentity
+            }
+            guard bindingChanged else { return }
+            self.saveIdentityCache()
+        }
+        if DispatchQueue.getSpecific(key: queueSpecificKey) != nil {
+            bindAndPersist()
+        } else {
+            queue.sync(flags: .barrier, execute: bindAndPersist)
+        }
+    }
+
+    func authenticatedSigningPublicKey(forFingerprint fingerprint: String) -> Data? {
+        guard !fingerprint.isEmpty else { return nil }
+        return queue.sync {
+            cache.authenticatedSigningKeysByFingerprint?[fingerprint]
+        }
+    }
+    
    func updateSocialIdentity(_ identity: SocialIdentity) {
        queue.async(flags: .barrier) {
            let previousClaimedNickname = self.cache.socialIdentities[identity.fingerprint]?.claimedNickname
@@ -511,11 +568,7 @@ final class SecureIdentityStateManager: SecureIdentityStateManagerProtocol {
    
    func registerEphemeralSession(peerID: PeerID, handshakeState: HandshakeState = .none) {
        queue.async(flags: .barrier) {
-            self.ephemeralSessions[peerID] = EphemeralIdentity(
-                peerID: peerID,
-                sessionStart: Date(),
-                handshakeState: handshakeState
-            )
+            self.ephemeralSessions[peerID] = EphemeralIdentity(handshakeState: handshakeState)
        }
    }
    
@@ -31,24 +31,20 @@
 	</array>
 	<key>CFBundleVersion</key>
 	<string>$(CURRENT_PROJECT_VERSION)</string>
+	<key>LSApplicationCategoryType</key>
+	<string>public.app-category.social-networking</string>
 	<key>LSMinimumSystemVersion</key>
 	<string>$(MACOSX_DEPLOYMENT_TARGET)</string>
-	<key>NSBonjourServices</key>
-	<array>
-		<string>_bitchat-bulk._tcp</string>
-	</array>
 	<key>NSBluetoothAlwaysUsageDescription</key>
 	<string>bitchat uses Bluetooth to create a secure mesh network for chatting with nearby users.</string>
 	<key>NSBluetoothPeripheralUsageDescription</key>
 	<string>bitchat uses Bluetooth to discover and connect with other bitchat users nearby.</string>
 	<key>NSCameraUsageDescription</key>
 	<string>bitchat uses the camera to scan QR codes to verify peers.</string>
-	<key>NSLocalNetworkUsageDescription</key>
-	<string>bitchat uses peer-to-peer Wi-Fi to transfer large photos and voice notes directly between nearby devices.</string>
 	<key>NSLocationWhenInUseUsageDescription</key>
-	<string>bitchat uses your approximate location to compute local geohash channels for optional public chats. Exact GPS is never shared.</string>
+	<string>bitchat uses your location to compute optional geohash channels, bridge cells, and nearby place labels. Exact coordinates are not included in bitchat messages.</string>
 	<key>NSMicrophoneUsageDescription</key>
-	<string>bitchat uses the microphone to record voice notes that relay across the mesh.</string>
+	<string>bitchat uses the microphone while you record voice notes or hold live push-to-talk, then sends that audio to your selected mesh conversation.</string>
 	<key>NSPhotoLibraryUsageDescription</key>
 	<string>bitchat lets you pick images from your photo library to share with nearby peers.</string>
 	<key>UIBackgroundModes</key>
@@ -13,13 +13,6 @@ extension BitchatMessage {
    enum Media {
        case voice(URL)
        case image(URL)
-
-        var url: URL {
-            switch self {
-            case .voice(let url), .image(let url):
-                return url
-            }
-        }
    }

    // Cache the directory lookup to avoid repeated FileManager calls during view rendering
@@ -7,7 +7,6 @@ struct BitchatPeer: Equatable {
    let peerID: PeerID // Hex-encoded peer ID
    let noisePublicKey: Data
    let nickname: String
-    let lastSeen: Date
    let isConnected: Bool
    let isReachable: Bool
    
@@ -77,14 +76,13 @@ struct BitchatPeer: Equatable {
        peerID: PeerID,
        noisePublicKey: Data,
        nickname: String,
-        lastSeen: Date = Date(),
+        lastSeen _: Date = Date(),
        isConnected: Bool = false,
        isReachable: Bool = false
    ) {
        self.peerID = peerID
        self.noisePublicKey = noisePublicKey
        self.nickname = nickname
-        self.lastSeen = lastSeen
        self.isConnected = isConnected
        self.isReachable = isReachable
        
@@ -28,6 +28,7 @@ enum CommandInfo: String, Identifiable {
    case unfavorite = "unfav"
    case ping
    case trace
+    case drop

    var id: String { rawValue }

@@ -36,11 +37,13 @@ enum CommandInfo: String, Identifiable {
    var placeholder: String? {
        switch self {
        case .block, .hug, .message, .slap, .unblock, .favorite, .unfavorite, .ping, .trace:
-            return "<" + String(localized: "content.input.nickname_placeholder", defaultValue: "nickname") + ">"
+            return "<" + String(localized: "content.input.nickname_placeholder") + ">"
        case .group:
-            return "<" + String(localized: "content.input.group_placeholder", defaultValue: "create|invite|leave|list") + ">"
+            return "<" + String(localized: "content.input.group_placeholder") + ">"
        case .pay:
-            return "<" + String(localized: "content.input.token_placeholder", defaultValue: "token") + ">"
+            return "<" + String(localized: "content.input.token_placeholder") + ">"
+        case .drop:
+            return "<" + String(localized: "content.input.note_placeholder") + ">"
        case .clear, .help, .who:
            return nil
        }
@@ -48,25 +51,26 @@ enum CommandInfo: String, Identifiable {

    var description: String {
        switch self {
-        case .block:        String(localized: "content.commands.block", defaultValue: "block or list blocked peers")
-        case .clear:        String(localized: "content.commands.clear", defaultValue: "clear chat messages")
-        case .group:        String(localized: "content.commands.group", defaultValue: "create or manage private groups")
-        case .help:         String(localized: "content.commands.help", defaultValue: "show available commands")
-        case .hug:          String(localized: "content.commands.hug", defaultValue: "send someone a warm hug")
-        case .message:      String(localized: "content.commands.message", defaultValue: "send private message")
-        case .pay:          String(localized: "content.commands.pay", defaultValue: "send a cashu ecash token in this chat")
-        case .slap:         String(localized: "content.commands.slap", defaultValue: "slap someone with a trout")
-        case .unblock:      String(localized: "content.commands.unblock", defaultValue: "unblock a peer")
-        case .who:          String(localized: "content.commands.who", defaultValue: "see who's online")
-        case .favorite:     String(localized: "content.commands.favorite", defaultValue: "add to favorites")
-        case .unfavorite:   String(localized: "content.commands.unfavorite", defaultValue: "remove from favorites")
-        case .ping:         String(localized: "content.commands.ping", defaultValue: "measure round-trip time to a mesh peer")
-        case .trace:        String(localized: "content.commands.trace", defaultValue: "estimate the mesh path to a peer")
+        case .block:        String(localized: "content.commands.block")
+        case .clear:        String(localized: "content.commands.clear")
+        case .group:        String(localized: "content.commands.group")
+        case .help:         String(localized: "content.commands.help")
+        case .hug:          String(localized: "content.commands.hug")
+        case .message:      String(localized: "content.commands.message")
+        case .pay:          String(localized: "content.commands.pay")
+        case .slap:         String(localized: "content.commands.slap")
+        case .unblock:      String(localized: "content.commands.unblock")
+        case .who:          String(localized: "content.commands.who")
+        case .favorite:     String(localized: "content.commands.favorite")
+        case .unfavorite:   String(localized: "content.commands.unfavorite")
+        case .ping:         String(localized: "content.commands.ping")
+        case .trace:        String(localized: "content.commands.trace")
+        case .drop:         String(localized: "content.commands.drop")
        }
    }

    static func all(isGeoPublic: Bool, isGeoDM: Bool) -> [CommandInfo] {
-        var commands: [CommandInfo] = [.block, .unblock, .clear, .help, .hug, .message, .slap, .who]
+        var commands: [CommandInfo] = [.block, .unblock, .clear, .drop, .help, .hug, .message, .slap, .who]
        // Cashu tokens are bearer instruments: in a public geohash any nearby
        // stranger can redeem one, so don't *suggest* /pay there (the
        // processor still allows it behind an explicit "public" confirm).
@@ -74,11 +78,11 @@ enum CommandInfo: String, Identifiable {
        if !isGeoPublic {
            commands.append(.pay)
        }
-        // The processor rejects favorites, groups and mesh diagnostics in
-        // geohash contexts, so only suggest them where they actually work: mesh.
+        // The processor rejects favorites, groups, and mesh diagnostics in
+        // geohash contexts, so only suggest them where they work: mesh.
        if isGeoPublic || isGeoDM {
            return commands
        }
-        return commands + [.favorite, .unfavorite, .group, .ping, .trace]
+        return commands + [.favorite, .unfavorite, .ping, .trace, .group]
    }
 }
@@ -30,7 +30,7 @@ struct NoisePayload {
        
        // Safely get the first byte
        let firstByte = data[data.startIndex]
-        guard let type = NoisePayloadType(rawValue: firstByte) else {
+        guard let type = NoisePayloadType.decoded(rawValue: firstByte) else {
            return nil
        }
        
@@ -723,7 +723,7 @@ final class NoiseHandshakeState {
        return messageBuffer
    }
    
-    func readMessage(_ message: Data, expectedPayloadLength: Int = 0) throws -> Data {
+    func readMessage(_ message: Data, expectedPayloadLength _: Int = 0) throws -> Data {
        
        guard currentPattern < messagePatterns.count else {
            throw NoiseError.handshakeComplete
@@ -6,27 +6,67 @@
 // For more information, see <https://unlicense.org>
 //

+import BitFoundation
 import Foundation

 enum NoiseSecurityConstants {
    // Maximum message size to prevent memory exhaustion
    static let maxMessageSize = 65535 // 64KB as per Noise spec

+    /// The extracted transport nonce (4 bytes) and Poly1305 tag (16 bytes)
+    /// added by `NoiseCipherState` around every transport plaintext.
+    static let transportCiphertextOverhead = 20
+
+    /// Private files are an explicit BitChat extension to the ordinary Noise
+    /// message-size ceiling. They remain bounded by the same framed-file cap
+    /// used by the binary and fragment decoders. Only the `.privateFile`
+    /// typed-payload path is allowed to use this larger budget.
+    private static let privateFileOuterPacketOverhead =
+        (BinaryProtocol.v1HeaderSize + 2) // v2 adds two length bytes
+        + BinaryProtocol.senderIDSize
+        + BinaryProtocol.recipientIDSize
+    static let maxPrivateFilePlaintextSize = FileTransferLimits.maxFramedFileBytes
+        - privateFileOuterPacketOverhead
+        - transportCiphertextOverhead
+    static let maxPrivateFileCiphertextSize =
+        maxPrivateFilePlaintextSize + transportCiphertextOverhead
+    
    // Maximum handshake message size
    static let maxHandshakeMessageSize = 2048 // 2KB to accommodate XX pattern

+    // Noise XX message 1 contains only the initiator's 32-byte ephemeral key.
+    static let xxInitialMessageSize = 32
+
+    // Bounds an ordinary initiator whose message 1 or 2 is lost.
+    static let ordinaryHandshakeTimeout: TimeInterval = 10
+
+    // Bounds the receive-only rollback quarantine created by an unauthenticated
+    // inbound message 1. A lost message 3 must not strand outbound traffic.
+    static let ordinaryResponderHandshakeTimeout: TimeInterval = 20
+
+    // A released client may immediately retry after both crossed initiators
+    // yielded. Give that unilateral retry a brief head start before the
+    // patched side spends its one bounded recovery.
+    static let handshakeCollisionRecoveryDelay: TimeInterval = 0.2
+
+    // Rate-limited recovery remains actionable without spinning.
+    static let handshakeRateLimitRecoveryDelay: TimeInterval = 60
+
+    // Covers only reordering between a winning message 3 and the losing
+    // crossed message 1.
+    static let recentInitiatorCompletionGracePeriod: TimeInterval = 1
+
+    // After unauthenticated responder rollback, reject another attempt long
+    // enough that paced message 1 traffic cannot keep outbound paused. A
+    // legitimate peer converges through the one manager-owned local retry.
+    static let ordinaryReconnectRollbackCooldown: TimeInterval = 60
+    
    // Session timeout - sessions older than this should be renegotiated
    static let sessionTimeout: TimeInterval = 86400 // 24 hours
    
    // Maximum number of messages before rekey (2^64 - 1 is the nonce limit)
    static let maxMessagesPerSession: UInt64 = 1_000_000_000 // 1 billion messages
    
-    // Handshake timeout - abandon incomplete handshakes
-    static let handshakeTimeout: TimeInterval = 60 // 1 minute
-    
-    // Maximum concurrent sessions per peer
-    static let maxSessionsPerPeer = 3
-    
    // Rate limiting
    static let maxHandshakesPerMinute = 10
    static let maxMessagesPerSecond = 100
@@ -14,5 +14,4 @@ enum NoiseSecurityError: Error {
    case messageTooLarge
    case invalidPeerID
    case rateLimitExceeded
-    case handshakeTimeout
 }
@@ -15,6 +15,19 @@ struct NoiseSecurityValidator {
        return data.count <= NoiseSecurityConstants.maxMessageSize
    }

+    static func validateCiphertextSize(_ data: Data) -> Bool {
+        data.count <= NoiseSecurityConstants.maxMessageSize
+            + NoiseSecurityConstants.transportCiphertextOverhead
+    }
+
+    static func validatePrivateFileMessageSize(_ data: Data) -> Bool {
+        data.count <= NoiseSecurityConstants.maxPrivateFilePlaintextSize
+    }
+
+    static func validatePrivateFileCiphertextSize(_ data: Data) -> Bool {
+        data.count <= NoiseSecurityConstants.maxPrivateFileCiphertextSize
+    }
+    
    /// Validate handshake message size
    static func validateHandshakeMessageSize(_ data: Data) -> Bool {
        return data.count <= NoiseSecurityConstants.maxHandshakeMessageSize
@@ -66,7 +66,10 @@ class NoiseSession {
            
            // Only initiator writes the first message
            if role == .initiator {
-                let message = try handshakeState!.writeMessage()
+                guard let handshake = handshakeState else {
+                    throw NoiseSessionError.invalidState
+                }
+                let message = try handshake.writeMessage()
                sentHandshakeMessages.append(message)
                return message
            } else {
@@ -11,4 +11,11 @@ enum NoiseSessionError: Error, Equatable {
    case notEstablished
    case sessionNotFound
    case alreadyEstablished
+    case peerIdentityMismatch
+}
+
+/// The manager owns the exact attempt's one bounded recovery. Packet handling
+/// must not launch its historical second, immediate restart for this failure.
+struct NoiseManagedHandshakeFailure: Error {
+    let underlying: Error
 }
@@ -24,8 +24,12 @@ final class SecureNoiseSession: NoiseSession {
            throw NoiseSecurityError.sessionExhausted
        }
        
-        // Validate message size
-        guard NoiseSecurityValidator.validateMessageSize(plaintext) else {
+        // Ordinary Noise messages keep the protocol ceiling. Finalized media
+        // is the sole typed-payload extension and remains under the framed-file
+        // cap enforced again at the service and file-decoder layers.
+        let isPrivateFile = NoisePayloadType.isPrivateFile(rawValue: plaintext.first)
+            && NoiseSecurityValidator.validatePrivateFileMessageSize(plaintext)
+        guard NoiseSecurityValidator.validateMessageSize(plaintext) || isPrivateFile else {
            throw NoiseSecurityError.messageTooLarge
        }
        
@@ -42,8 +46,11 @@ final class SecureNoiseSession: NoiseSession {
            throw NoiseSecurityError.sessionExpired
        }
        
-        // Validate message size
-        guard NoiseSecurityValidator.validateMessageSize(ciphertext) else {
+        // The payload type is encrypted, so a large candidate can only be
+        // bounded here; `NoiseEncryptionService.decrypt` authenticates it and
+        // then requires the resulting type to be `.privateFile`.
+        guard NoiseSecurityValidator.validateCiphertextSize(ciphertext)
+                || NoiseSecurityValidator.validatePrivateFileCiphertextSize(ciphertext) else {
            throw NoiseSecurityError.messageTooLarge
        }
        
@@ -1,19 +1,18 @@
 import Foundation
 import P256K

-/// Manages Nostr identity (secp256k1 keypair) for NIP-17 private messaging
+/// Manages the secp256k1 identity used by BitChat's Nostr relay features,
+/// including the proprietary private-envelope transport.
 struct NostrIdentity: Codable {
    let privateKey: Data
    let publicKey: Data
    let npub: String // Bech32-encoded public key
-    let createdAt: Date

    /// Memberwise initializer
-    init(privateKey: Data, publicKey: Data, npub: String, createdAt: Date) {
+    init(privateKey: Data, publicKey: Data, npub: String, createdAt _: Date) {
        self.privateKey = privateKey
        self.publicKey = publicKey
        self.npub = npub
-        self.createdAt = createdAt
    }
    
    /// Generate a new Nostr identity
@@ -39,12 +38,6 @@ struct NostrIdentity: Codable {
        self.privateKey = privateKeyData
        self.publicKey = xOnlyPubkey
        self.npub = try Bech32.encode(hrp: "npub", data: xOnlyPubkey)
-        self.createdAt = Date()
-    }
-    
-    /// Get signing key for event signatures
-    func signingKey() throws -> P256K.Signing.PrivateKey {
-        try P256K.Signing.PrivateKey(dataRepresentation: privateKey)
    }
    
    /// Get Schnorr signing key for Nostr event signatures
@@ -15,7 +15,7 @@ final class NostrIdentityBridge {

    private let keychain: KeychainManagerProtocol

-    init(keychain: KeychainManagerProtocol = KeychainManager()) {
+    init(keychain: KeychainManagerProtocol = KeychainManager.makeDefault()) {
        self.keychain = keychain
    }
    
@@ -37,14 +37,6 @@ final class NostrIdentityBridge {
        return nostrIdentity
    }
    
-    /// Associate a Nostr identity with a Noise public key (for favorites)
-    func associateNostrIdentity(_ nostrPubkey: String, with noisePublicKey: Data) {
-        let key = "nostr-noise-\(noisePublicKey.base64EncodedString())"
-        if let data = nostrPubkey.data(using: .utf8) {
-            keychain.save(key: key, data: data, service: keychainService, accessible: nil)
-        }
-    }
-    
    /// Get Nostr public key associated with a Noise public key
    func getNostrPublicKey(for noisePublicKey: Data) -> String? {
        let key = "nostr-noise-\(noisePublicKey.base64EncodedString())"
@@ -57,29 +49,10 @@ final class NostrIdentityBridge {
    
    /// Clear all Nostr identity associations and current identity
    func clearAllAssociations() {
-        let query: [String: Any] = [
-            kSecClass as String: kSecClassGenericPassword,
-            kSecAttrService as String: keychainService,
-            kSecMatchLimit as String: kSecMatchLimitAll,
-            kSecReturnAttributes as String: true
-        ]
-
-        var result: AnyObject?
-        let status = SecItemCopyMatching(query as CFDictionary, &result)
-        if status == errSecSuccess, let items = result as? [[String: Any]] {
-            for item in items {
-                var deleteQuery: [String: Any] = [
-                    kSecClass as String: kSecClassGenericPassword,
-                    kSecAttrService as String: keychainService
-                ]
-                if let account = item[kSecAttrAccount as String] as? String {
-                    deleteQuery[kSecAttrAccount as String] = account
-                }
-                SecItemDelete(deleteQuery as CFDictionary)
-            }
-        } else if status == errSecItemNotFound {
-            // nothing persisted; no action needed
-        }
+        // Must go through the injected keychain, not raw SecItem calls:
+        // under test that keychain is in-memory, and a direct delete here
+        // would wipe the developer's real Nostr identity on every test run.
+        keychain.deleteAll(service: keychainService)

        deviceSeedCache = nil
        // Also drop the in-memory derived per-geohash identities. These hold the
@@ -113,6 +86,13 @@ final class NostrIdentityBridge {
        return seed
    }

+    /// Derive a deterministic, unlinkable Nostr identity for a mesh-bridge
+    /// rendezvous cell. Distinct HMAC label keeps it unlinkable from the
+    /// geohash-chat identity for the same cell string.
+    func deriveIdentity(forBridgeRendezvous cell: String) throws -> NostrIdentity {
+        try deriveIdentity(forGeohash: "bridge|" + cell)
+    }
+
    /// Derive a deterministic, unlinkable Nostr identity for a given geohash.
    /// Uses HMAC-SHA256(deviceSeed, geohash) as private key material, with fallback rehashing
    /// if the candidate is not a valid secp256k1 private key.
@@ -0,0 +1,41 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>NSPrivacyTracking</key>
+	<false/>
+	<key>NSPrivacyTrackingDomains</key>
+	<array/>
+	<key>NSPrivacyCollectedDataTypes</key>
+	<array/>
+	<key>NSPrivacyAccessedAPITypes</key>
+	<array>
+		<dict>
+			<key>NSPrivacyAccessedAPIType</key>
+			<string>NSPrivacyAccessedAPICategoryFileTimestamp</string>
+			<key>NSPrivacyAccessedAPITypeReasons</key>
+			<array>
+				<string>C617.1</string>
+				<string>3B52.1</string>
+			</array>
+		</dict>
+		<dict>
+			<key>NSPrivacyAccessedAPIType</key>
+			<string>NSPrivacyAccessedAPICategorySystemBootTime</string>
+			<key>NSPrivacyAccessedAPITypeReasons</key>
+			<array>
+				<string>35F9.1</string>
+			</array>
+		</dict>
+		<dict>
+			<key>NSPrivacyAccessedAPIType</key>
+			<string>NSPrivacyAccessedAPICategoryUserDefaults</string>
+			<key>NSPrivacyAccessedAPITypeReasons</key>
+			<array>
+				<string>CA92.1</string>
+				<string>1C8F.1</string>
+			</array>
+		</dict>
+	</array>
+</dict>
+</plist>
@@ -28,14 +28,12 @@ struct BitchatFilePacket {

    /// Encodes the packet using v2 canonical TLVs (4-byte FILE_SIZE, 4-byte CONTENT length).
    /// Returns `nil` when fields exceed protocol limits (e.g., content > UInt32.max).
-    /// `limit` defaults to the Bluetooth payload cap; Wi-Fi bulk transfers pass
-    /// `FileTransferLimits.maxWifiBulkPayloadBytes`.
-    func encode(limit: Int = FileTransferLimits.maxPayloadBytes) -> Data? {
+    func encode() -> Data? {
        let resolvedSize = fileSize ?? UInt64(content.count)
        guard resolvedSize <= UInt64(UInt32.max) else { return nil }
-        guard resolvedSize <= UInt64(limit) else { return nil }
+        guard resolvedSize <= UInt64(FileTransferLimits.maxPayloadBytes) else { return nil }
        guard content.count <= Int(UInt32.max) else { return nil }
-        guard FileTransferLimits.isValidPayload(content.count, limit: limit) else { return nil }
+        guard FileTransferLimits.isValidPayload(content.count) else { return nil }

        func appendBE<T: FixedWidthInteger>(_ value: T, into data: inout Data) {
            var big = value.bigEndian
@@ -68,9 +66,7 @@ struct BitchatFilePacket {
    }

    /// Decodes TLV payloads, tolerating legacy encodings (FILE_SIZE len=8, CONTENT len=2) when possible.
-    /// `limit` defaults to the Bluetooth payload cap; Wi-Fi bulk transfers pass
-    /// the (smaller of the) accepted-offer size and the Wi-Fi bulk ceiling.
-    static func decode(_ data: Data, limit: Int = FileTransferLimits.maxPayloadBytes) -> BitchatFilePacket? {
+    static func decode(_ data: Data) -> BitchatFilePacket? {
        var cursor = data.startIndex
        let end = data.endIndex

@@ -130,7 +126,7 @@ struct BitchatFilePacket {
                    for byte in value {
                        size = (size << 8) | UInt64(byte)
                    }
-                    if size > UInt64(limit) {
+                    if size > UInt64(FileTransferLimits.maxPayloadBytes) {
                        return nil
                    }
                    fileSize = size
@@ -139,7 +135,7 @@ struct BitchatFilePacket {
                mimeType = String(data: Data(value), encoding: .utf8)
            case .content:
                let proposedSize = content.count + value.count
-                if proposedSize > limit {
+                if proposedSize > FileTransferLimits.maxPayloadBytes {
                    return nil
                }
                content.append(contentsOf: value)
@@ -149,7 +145,7 @@ struct BitchatFilePacket {
        }

        guard !content.isEmpty else { return nil }
-        guard FileTransferLimits.isValidPayload(content.count, limit: limit) else { return nil }
+        guard FileTransferLimits.isValidPayload(content.count) else { return nil }
        return BitchatFilePacket(
            fileName: fileName,
            fileSize: fileSize ?? UInt64(content.count),
@@ -158,3 +154,90 @@ struct BitchatFilePacket {
        )
    }
 }
+
+/// Wire-compatible identity for private media exchanged by clients using the
+/// current iOS entropy-bearing filenames, without extending the deployed file
+/// TLV. Android clients reject unknown file tags, so eligible senders and
+/// receivers derive the receipt key from fields already on the wire.
+///
+/// Locally-created image and voice-note filenames contain a UUID or live-voice
+/// burst ID. Including the normalized direction keeps a reused filename
+/// distinct across chats while allowing short and full Noise-key peer IDs to
+/// converge. Android and older-iOS timestamp-only names remain ineligible and
+/// retain their legacy random local IDs (transfer-compatible, no receipts).
+enum PrivateMediaMessageIdentity {
+    private static let domain = Data("bitchat-private-media-message-v1".utf8)
+    private static let idPrefix = "media-"
+    private static let digestHexLength = 32
+
+    static func isStableID(_ candidate: String) -> Bool {
+        guard candidate.hasPrefix(idPrefix) else { return false }
+        let digest = candidate.dropFirst(idPrefix.count)
+        guard digest.utf8.count == digestHexLength else { return false }
+        return digest.utf8.allSatisfy { byte in
+            (UInt8(ascii: "0")...UInt8(ascii: "9")).contains(byte)
+                || (UInt8(ascii: "a")...UInt8(ascii: "f")).contains(byte)
+        }
+    }
+
+    static func stableID(
+        senderPeerID: PeerID,
+        recipientPeerID: PeerID,
+        fileName: String?
+    ) -> String? {
+        guard let fileName, !fileName.isEmpty else { return nil }
+        let leafName = (fileName as NSString).lastPathComponent
+        guard leafName == fileName else { return nil }
+
+        let path = leafName as NSString
+        let stem = path.deletingPathExtension
+        let fileExtension = path.pathExtension.lowercased()
+        switch true {
+        case stem.hasPrefix("img_"):
+            guard fileExtension == "jpg" || fileExtension == "jpeg" else { return nil }
+        case stem.hasPrefix("voice_"):
+            guard fileExtension == "m4a" else { return nil }
+        default:
+            return nil
+        }
+        let entropyToken = stem.split(separator: "_").last.map(String.init)
+        let hasUUIDEntropy = entropyToken.flatMap(UUID.init(uuidString:)) != nil
+        let voiceBurstID = stem.hasPrefix("voice_")
+            ? String(stem.dropFirst("voice_".count))
+            : ""
+        let hasBurstEntropy = voiceBurstID.count == 16
+            && voiceBurstID.allSatisfy(\.isHexDigit)
+        guard hasUUIDEntropy || hasBurstEntropy else {
+            return nil
+        }
+
+        let fields = [
+            Data(senderPeerID.toShort().bare.utf8),
+            Data(recipientPeerID.toShort().bare.utf8),
+            Data(leafName.utf8)
+        ]
+        var input = domain
+        for field in fields {
+            guard let length = UInt32(exactly: field.count) else { return nil }
+            var bigEndianLength = length.bigEndian
+            withUnsafeBytes(of: &bigEndianLength) {
+                input.append(contentsOf: $0)
+            }
+            input.append(field)
+        }
+
+        return "\(idPrefix)\(input.sha256Hex().prefix(digestHexLength))"
+    }
+
+    static func stableID(
+        for packet: BitchatFilePacket,
+        senderPeerID: PeerID,
+        recipientPeerID: PeerID
+    ) -> String? {
+        stableID(
+            senderPeerID: senderPeerID,
+            recipientPeerID: recipientPeerID,
+            fileName: packet.fileName
+        )
+    }
+}
@@ -74,27 +74,50 @@ enum NoisePayloadType: UInt8 {
    case privateMessage = 0x01      // Private chat message
    case readReceipt = 0x02         // Message was read
    case delivered = 0x03           // Message was delivered
-    // Wi-Fi bulk transport negotiation (AWDL data plane for large media)
-    case bulkTransferOffer = 0x04    // Offer to move a large file over peer-to-peer Wi-Fi
-    case bulkTransferResponse = 0x05 // Accept/decline reply to a bulk transfer offer
-    // Private groups
+    // Private groups (0x04/0x05 reserved by other features)
    case groupInvite = 0x06         // Creator-signed group state (invite)
    case groupKeyUpdate = 0x07      // Creator-signed group state (key rotation / roster update)
+    // Live voice (push-to-talk)
+    case voiceFrame = 0x08          // One live voice-burst packet (see VoiceBurstPacket)
+    // Finalized private media. `0x20` is the value already deployed by the
+    // Android client. The complete BitchatFilePacket is encrypted inside
+    // Noise before the outer noiseEncrypted packet is fragmented.
+    case privateFile = 0x20
+    // Versioned peer state authenticated by the surrounding Noise session.
+    // This is intentionally distinct from the public announce: announce
+    // capabilities are discovery hints, while this payload proves possession
+    // of the advertised Noise static key before downgrade state is pinned.
+    case authenticatedPeerState = 0x21
    // Verification (QR-based OOB binding)
    case verifyChallenge = 0x10     // Verification challenge
    case verifyResponse  = 0x11     // Verification response
    // Transitive verification (web of trust)
    case vouch = 0x12               // Batch of vouch attestations

+    /// #1434 briefly used 0x09 before release. Accept it while prerelease
+    /// builds age out, but never emit it. Decoders canonicalize both values to
+    /// `.privateFile` so the compatibility alias cannot leak into app logic.
+    static let prereleasePrivateFileRawValue: UInt8 = 0x09
+
+    static func decoded(rawValue: UInt8) -> NoisePayloadType? {
+        rawValue == prereleasePrivateFileRawValue ? .privateFile : Self(rawValue: rawValue)
+    }
+
+    static func isPrivateFile(rawValue: UInt8?) -> Bool {
+        guard let rawValue else { return false }
+        return rawValue == privateFile.rawValue || rawValue == prereleasePrivateFileRawValue
+    }
+
    var description: String {
        switch self {
        case .privateMessage: return "privateMessage"
        case .readReceipt: return "readReceipt"
        case .delivered: return "delivered"
-        case .bulkTransferOffer: return "bulkTransferOffer"
-        case .bulkTransferResponse: return "bulkTransferResponse"
        case .groupInvite: return "groupInvite"
        case .groupKeyUpdate: return "groupKeyUpdate"
+        case .voiceFrame: return "voiceFrame"
+        case .privateFile: return "privateFile"
+        case .authenticatedPeerState: return "authenticatedPeerState"
        case .verifyChallenge: return "verifyChallenge"
        case .verifyResponse: return "verifyResponse"
        case .vouch: return "vouch"
@@ -132,6 +155,9 @@ protocol BitchatDelegate: AnyObject {
    // Encrypted group broadcast (opaque envelope; decrypted by the group coordinator)
    func didReceiveGroupMessage(payload: Data, timestamp: Date)

+    // Public live-voice burst packet (signature-verified by the transport)
+    func didReceivePublicVoiceFrame(from peerID: PeerID, nickname: String, payload: Data, timestamp: Date)
+
    // Bluetooth state updates for user notifications
    func didUpdateBluetoothState(_ state: CBManagerState)
    func didReceivePublicMessage(from peerID: PeerID, nickname: String, content: String, timestamp: Date, messageID: String?)
@@ -155,6 +181,10 @@ extension BitchatDelegate {
        // Default empty implementation
    }

+    func didReceivePublicVoiceFrame(from peerID: PeerID, nickname: String, payload: Data, timestamp: Date) {
+        // Default empty implementation
+    }
+
    func didReceivePublicMessage(from peerID: PeerID, nickname: String, content: String, timestamp: Date, messageID: String?) {
        // Default empty implementation
    }
@@ -10,11 +10,11 @@ enum Geohash {
        return map
    }()

-    /// Validates a geohash string for building-level precision (8 characters).
+    /// Validates a geohash string at any channel precision (1-12 characters).
    /// - Parameter geohash: The geohash string to validate
-    /// - Returns: true if valid 8-character base32 geohash, false otherwise
-    static func isValidBuildingGeohash(_ geohash: String) -> Bool {
-        guard geohash.count == 8 else { return false }
+    /// - Returns: true if a non-empty base32 geohash of at most 12 characters
+    static func isValidGeohash(_ geohash: String) -> Bool {
+        guard (1...12).contains(geohash.count) else { return false }
        return geohash.lowercased().allSatisfy { base32Map[$0] != nil }
    }

@@ -24,17 +24,17 @@ enum GeohashChannelLevel: CaseIterable, Codable, Equatable {
    var displayName: String {
        switch self {
        case .building:
-            return String(localized: "location_levels.building", defaultValue: "building", comment: "Name for building-level location channel")
+            return String(localized: "location_levels.building", comment: "Name for building-level location channel")
        case .block:
-            return String(localized: "location_levels.block", defaultValue: "block", comment: "Name for block-level location channel")
+            return String(localized: "location_levels.block", comment: "Name for block-level location channel")
        case .neighborhood:
-            return String(localized: "location_levels.neighborhood", defaultValue: "neighborhood", comment: "Name for neighborhood-level location channel")
+            return String(localized: "location_levels.neighborhood", comment: "Name for neighborhood-level location channel")
        case .city:
-            return String(localized: "location_levels.city", defaultValue: "city", comment: "Name for city-level location channel")
+            return String(localized: "location_levels.city", comment: "Name for city-level location channel")
        case .province:
-            return String(localized: "location_levels.province", defaultValue: "province", comment: "Name for province-level location channel")
+            return String(localized: "location_levels.province", comment: "Name for province-level location channel")
        case .region:
-            return String(localized: "location_levels.region", defaultValue: "region", comment: "Name for region-level location channel")
+            return String(localized: "location_levels.region", comment: "Name for region-level location channel")
        }
    }
 }
@@ -0,0 +1,32 @@
+//
+// MeshMessageIdentity.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import BitFoundation
+import Foundation
+
+/// Content-derived identity for public mesh messages.
+///
+/// The BLE wire carries no message ID for public broadcasts, so every device
+/// recomputes the same stable ID from the signed wire fields (sender ID,
+/// millisecond timestamp, content). That gives the mesh bridge a
+/// cross-device-consistent radio identity with zero wire change. Bridge events
+/// carry this value only as a hint for detecting a radio copy that is already
+/// present: sender/timestamp/content are public, so a different Nostr signer
+/// can copy them and must never be allowed to reserve the genuine event's
+/// authenticated dedup slot.
+enum MeshMessageIdentity {
+    /// Matches the wire truncation in `BLEService.sendMessage`.
+    static func millisecondTimestamp(_ date: Date) -> UInt64 {
+        UInt64(date.timeIntervalSince1970 * 1000)
+    }
+
+    static func stableID(senderIDHex: String, timestampMs: UInt64, content: String) -> String {
+        let input = senderIDHex.lowercased() + "|" + String(timestampMs) + "|" + content.trimmed
+        return String(Data(input.utf8).sha256Hex().prefix(32))
+    }
+}
@@ -32,6 +32,14 @@ struct NostrCarrierPacket: Equatable {
    enum Direction: UInt8 {
        case toGateway = 0x01
        case fromGateway = 0x02
+        /// Mesh-bridge uplink: a mesh-only peer asks a bridge gateway to
+        /// publish its signed rendezvous event. Directed, like `toGateway`.
+        case toBridge = 0x03
+        /// Mesh-bridge downlink: a bridge gateway rebroadcasts a rendezvous
+        /// event from a remote island. Broadcast, like `fromGateway`.
+        /// Old clients fail the Direction decode on 0x03/0x04 and drop the
+        /// carrier quietly — bridge traffic degrades to invisible, not junk.
+        case fromBridge = 0x04
    }

    let direction: Direction
@@ -9,19 +9,25 @@ struct AnnouncementPacket {
    let signingPublicKey: Data          // Ed25519 public key for signing
    let directNeighbors: [Data]?        // 8-byte peer IDs
    let capabilities: PeerCapabilities? // advertised feature bits; nil when absent (old clients)
+    /// Rendezvous geohash cell this peer bridges, when advertising `.bridge`.
+    /// Coarse (cell-level) by design; lets mesh-only peers compose correctly
+    /// tagged rendezvous events without their own location fix.
+    let bridgeGeohash: String?

    init(
        nickname: String,
        noisePublicKey: Data,
        signingPublicKey: Data,
        directNeighbors: [Data]?,
-        capabilities: PeerCapabilities? = nil
+        capabilities: PeerCapabilities? = nil,
+        bridgeGeohash: String? = nil
    ) {
        self.nickname = nickname
        self.noisePublicKey = noisePublicKey
        self.signingPublicKey = signingPublicKey
        self.directNeighbors = directNeighbors
        self.capabilities = capabilities
+        self.bridgeGeohash = bridgeGeohash
    }

    private enum TLVType: UInt8 {
@@ -30,6 +36,7 @@ struct AnnouncementPacket {
        case signingPublicKey = 0x03
        case directNeighbors = 0x04
        case capabilities = 0x05
+        case bridgeGeohash = 0x06
    }

    func encode() -> Data? {
@@ -74,6 +81,15 @@ struct AnnouncementPacket {
            data.append(capabilityBytes)
        }

+        // TLV for bridge rendezvous cell (optional; old clients skip it)
+        if let bridgeGeohash = bridgeGeohash,
+           let cellData = bridgeGeohash.data(using: .utf8),
+           !cellData.isEmpty, cellData.count <= 12 {
+            data.append(TLVType.bridgeGeohash.rawValue)
+            data.append(UInt8(cellData.count))
+            data.append(cellData)
+        }
+
        return data
    }

@@ -84,6 +100,7 @@ struct AnnouncementPacket {
        var signingPublicKey: Data?
        var directNeighbors: [Data]?
        var capabilities: PeerCapabilities?
+        var bridgeGeohash: String?

        while offset + 2 <= data.count {
            let typeRaw = data[offset]
@@ -116,6 +133,10 @@ struct AnnouncementPacket {
                    }
                case .capabilities:
                    capabilities = PeerCapabilities(encoded: Data(value))
+                case .bridgeGeohash:
+                    if length <= 12 {
+                        bridgeGeohash = String(data: value, encoding: .utf8)
+                    }
                }
            } else {
                // Unknown TLV; skip (tolerant decoder for forward compatibility)
@@ -129,7 +150,91 @@ struct AnnouncementPacket {
            noisePublicKey: noisePublicKey,
            signingPublicKey: signingPublicKey,
            directNeighbors: directNeighbors,
-            capabilities: capabilities
+            capabilities: capabilities,
+            bridgeGeohash: bridgeGeohash
+        )
+    }
+}
+
+/// State that is authoritative only because it is carried inside an
+/// established Noise session. The public announce remains useful for
+/// discovery, but its self-signature cannot prove possession of the copied
+/// Noise public key it contains.
+///
+/// Wire format (v1):
+/// `[version=0x01][type][length][value]...`
+/// - TLV `0x01`: canonical minimal little-endian `PeerCapabilities`
+/// - TLV `0x02`: 32-byte Ed25519 signing public key
+///
+/// Unknown TLVs are skipped for forward compatibility. Unknown versions,
+/// duplicates, non-canonical capability fields, and malformed lengths are
+/// rejected without changing authenticated state.
+struct AuthenticatedPeerStatePacket: Equatable {
+    static let currentVersion: UInt8 = 1
+    static let signingPublicKeyLength = 32
+
+    let capabilities: PeerCapabilities
+    let signingPublicKey: Data
+
+    private enum TLVType: UInt8 {
+        case capabilities = 0x01
+        case signingPublicKey = 0x02
+    }
+
+    func encode() -> Data? {
+        guard signingPublicKey.count == Self.signingPublicKeyLength else { return nil }
+        let capabilityBytes = capabilities.encoded()
+        guard !capabilityBytes.isEmpty, capabilityBytes.count <= 8 else { return nil }
+
+        var data = Data([Self.currentVersion])
+        data.append(TLVType.capabilities.rawValue)
+        data.append(UInt8(capabilityBytes.count))
+        data.append(capabilityBytes)
+        data.append(TLVType.signingPublicKey.rawValue)
+        data.append(UInt8(signingPublicKey.count))
+        data.append(signingPublicKey)
+        return data
+    }
+
+    static func decode(from data: Data) -> AuthenticatedPeerStatePacket? {
+        guard data.first == Self.currentVersion else { return nil }
+
+        var offset = 1
+        var capabilities: PeerCapabilities?
+        var signingPublicKey: Data?
+
+        while offset < data.count {
+            guard offset + 2 <= data.count else { return nil }
+            let typeRaw = data[offset]
+            let length = Int(data[offset + 1])
+            offset += 2
+            guard offset + length <= data.count else { return nil }
+            let value = Data(data[offset..<(offset + length)])
+            offset += length
+
+            guard let type = TLVType(rawValue: typeRaw) else {
+                continue
+            }
+            switch type {
+            case .capabilities:
+                guard capabilities == nil,
+                      !value.isEmpty,
+                      value.count <= 8 else { return nil }
+                let decoded = PeerCapabilities(encoded: value)
+                guard decoded.encoded() == value else { return nil }
+                capabilities = decoded
+
+            case .signingPublicKey:
+                guard signingPublicKey == nil,
+                      value.count == Self.signingPublicKeyLength else { return nil }
+                signingPublicKey = value
+            }
+        }
+
+        guard let capabilities, let signingPublicKey else { return nil }
+        return AuthenticatedPeerStatePacket(
+            capabilities: capabilities,
+            signingPublicKey: signingPublicKey
        )
    }
 }
@@ -3,9 +3,11 @@ import BitFoundation
 extension PeerCapabilities {
    /// Capabilities this build advertises in its announce packets.
    /// Each feature adds its bit here when it ships.
-    static let localSupported: PeerCapabilities = {
-        var caps: PeerCapabilities = [.prekeys, .vouch, .groups]
-        if TransportConfig.wifiBulkEnabled { caps.insert(.wifiBulk) }
-        return caps
-    }()
+    static let localSupported: PeerCapabilities = [
+        .vouch,
+        .prekeys,
+        .groups,
+        .privateMedia,
+        .privateMediaReceipts
+    ]
 }
@@ -0,0 +1,220 @@
+//
+// VoiceBurstPacket.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import Foundation
+import Security
+
+/// Audio codec of a live voice burst. START packets carry it so receivers can
+/// reject bursts they can't decode instead of feeding garbage to the decoder.
+enum VoiceBurstCodec: UInt8 {
+    /// AAC-LC, 16 kHz, mono, ~16 kbps — matches the voice-note recorder, so
+    /// the finalized `.m4a` and the live frames come from the same encoder
+    /// settings.
+    case aacLC16kMono = 0x01
+}
+
+/// One packet of a live push-to-talk voice burst (the inner payload of
+/// `NoisePayloadType.voiceFrame`, and — for public mesh bursts — the payload
+/// of `MessageType.voiceFrame`).
+///
+/// Wire format:
+/// ```
+/// [burstID: 8][seq: UInt16 BE][flags: UInt8][payload…]
+/// ```
+/// - flags 0x01 (START): payload = [codec: UInt8]
+/// - flags 0x02 (END):   payload = [totalDataPackets: UInt16 BE][durationMs: UInt32 BE]
+/// - flags 0x04 (CANCELED): empty payload; receivers discard the burst
+/// - flags 0x00 (data):  payload = repeated [length: UInt16 BE][AAC frame]
+struct VoiceBurstPacket: Equatable {
+    enum Kind: Equatable {
+        case start(codec: VoiceBurstCodec)
+        case frames([Data])
+        case end(totalDataPackets: UInt16, durationMs: UInt32)
+        case canceled
+    }
+
+    static let burstIDSize = 8
+    private static let headerSize = burstIDSize + 2 + 1
+    /// Sanity cap on frames per packet; real packets carry 1-2 frames.
+    static let maxFramesPerPacket = 8
+
+    private enum Flags {
+        static let start: UInt8 = 0x01
+        static let end: UInt8 = 0x02
+        static let canceled: UInt8 = 0x04
+    }
+
+    let burstID: Data
+    let seq: UInt16
+    let kind: Kind
+
+    init?(burstID: Data, seq: UInt16, kind: Kind) {
+        guard burstID.count == Self.burstIDSize else { return nil }
+        if case .frames(let frames) = kind {
+            guard !frames.isEmpty,
+                  frames.count <= Self.maxFramesPerPacket,
+                  frames.allSatisfy({ !$0.isEmpty && $0.count <= Int(UInt16.max) })
+            else { return nil }
+        }
+        self.burstID = burstID
+        self.seq = seq
+        self.kind = kind
+    }
+
+    func encode() -> Data {
+        var data = Data(capacity: Self.headerSize + payloadSize)
+        data.append(burstID)
+        data.append(UInt8((seq >> 8) & 0xFF))
+        data.append(UInt8(seq & 0xFF))
+        switch kind {
+        case .start(let codec):
+            data.append(Flags.start)
+            data.append(codec.rawValue)
+        case .frames(let frames):
+            data.append(0)
+            for frame in frames {
+                let length = UInt16(frame.count)
+                data.append(UInt8((length >> 8) & 0xFF))
+                data.append(UInt8(length & 0xFF))
+                data.append(frame)
+            }
+        case .end(let totalDataPackets, let durationMs):
+            data.append(Flags.end)
+            data.append(UInt8((totalDataPackets >> 8) & 0xFF))
+            data.append(UInt8(totalDataPackets & 0xFF))
+            for shift in stride(from: 24, through: 0, by: -8) {
+                data.append(UInt8((durationMs >> UInt32(shift)) & 0xFF))
+            }
+        case .canceled:
+            data.append(Flags.canceled)
+        }
+        return data
+    }
+
+    static func decode(_ data: Data) -> VoiceBurstPacket? {
+        // Work on a re-based copy so subscripting is offset-safe.
+        let data = Data(data)
+        guard data.count >= headerSize else { return nil }
+
+        let burstID = data.prefix(burstIDSize)
+        let seq = (UInt16(data[burstIDSize]) << 8) | UInt16(data[burstIDSize + 1])
+        let flags = data[burstIDSize + 2]
+        let payload = data.dropFirst(headerSize)
+
+        let kind: Kind
+        switch flags {
+        case Flags.start:
+            guard let codecByte = payload.first,
+                  let codec = VoiceBurstCodec(rawValue: codecByte)
+            else { return nil }
+            kind = .start(codec: codec)
+        case Flags.end:
+            guard payload.count >= 6 else { return nil }
+            let bytes = Array(payload)
+            let total = (UInt16(bytes[0]) << 8) | UInt16(bytes[1])
+            let duration = bytes[2...5].reduce(UInt32(0)) { ($0 << 8) | UInt32($1) }
+            kind = .end(totalDataPackets: total, durationMs: duration)
+        case Flags.canceled:
+            kind = .canceled
+        case 0:
+            var frames: [Data] = []
+            var offset = payload.startIndex
+            while offset < payload.endIndex {
+                guard payload.distance(from: offset, to: payload.endIndex) >= 2 else { return nil }
+                let length = (Int(payload[offset]) << 8) | Int(payload[payload.index(after: offset)])
+                offset = payload.index(offset, offsetBy: 2)
+                guard length > 0,
+                      payload.distance(from: offset, to: payload.endIndex) >= length,
+                      frames.count < maxFramesPerPacket
+                else { return nil }
+                let end = payload.index(offset, offsetBy: length)
+                frames.append(Data(payload[offset..<end]))
+                offset = end
+            }
+            guard !frames.isEmpty else { return nil }
+            kind = .frames(frames)
+        default:
+            return nil
+        }
+
+        return VoiceBurstPacket(burstID: Data(burstID), seq: seq, kind: kind)
+    }
+
+    static func makeBurstID() -> Data {
+        var bytes = Data(count: burstIDSize)
+        let result = bytes.withUnsafeMutableBytes {
+            SecRandomCopyBytes(kSecRandomDefault, burstIDSize, $0.baseAddress!)
+        }
+        guard result == errSecSuccess else {
+            return Data((0..<burstIDSize).map { _ in UInt8.random(in: .min ... .max) })
+        }
+        return bytes
+    }
+
+    private var payloadSize: Int {
+        switch kind {
+        case .start: return 1
+        case .frames(let frames): return frames.reduce(0) { $0 + 2 + $1.count }
+        case .end: return 6
+        case .canceled: return 0
+        }
+    }
+}
+
+/// Greedy packetizer for outgoing bursts: batches encoded frames into
+/// `VoiceBurstPacket`s without exceeding the byte budget that keeps each
+/// packet in a single BLE frame after Noise encryption and padding.
+/// Not thread-safe — confine to one queue.
+struct VoiceBurstPacketizer {
+    let burstID: Data
+    private let budget: Int
+    private var pendingFrames: [Data] = []
+    private var pendingSize = 0
+    /// seq 0 is reserved for START; data packets start at 1.
+    private(set) var nextSeq: UInt16 = 1
+    private(set) var dataPacketCount: UInt16 = 0
+
+    init(burstID: Data, budget: Int = TransportConfig.pttMaxBurstContentBytes) {
+        self.burstID = burstID
+        self.budget = budget
+    }
+
+    /// Adds one encoded frame, returning any packets that became full.
+    /// Frames larger than the budget are dropped (the encoder's ~130-byte
+    /// frames never hit this; it guards against misconfiguration looping).
+    mutating func add(_ frame: Data) -> [Data] {
+        let frameCost = 2 + frame.count
+        guard VoiceBurstPacket.burstIDSize + 3 + frameCost <= budget else { return [] }
+
+        var packets: [Data] = []
+        if !pendingFrames.isEmpty,
+           VoiceBurstPacket.burstIDSize + 3 + pendingSize + frameCost > budget
+            || pendingFrames.count >= VoiceBurstPacket.maxFramesPerPacket {
+            packets.append(contentsOf: flush())
+        }
+        pendingFrames.append(frame)
+        pendingSize += frameCost
+        return packets
+    }
+
+    /// Emits any buffered frames as a final data packet.
+    mutating func flush() -> [Data] {
+        guard !pendingFrames.isEmpty,
+              let packet = VoiceBurstPacket(burstID: burstID, seq: nextSeq, kind: .frames(pendingFrames))
+        else {
+            pendingFrames = []
+            pendingSize = 0
+            return []
+        }
+        pendingFrames = []
+        pendingSize = 0
+        nextSeq &+= 1
+        dataPacketCount &+= 1
+        return [packet.encode()]
+    }
+}
@@ -11,13 +11,6 @@ import Foundation
 /// Manages autocomplete functionality for chat
 final class AutocompleteService {
    private let mentionRegex = try? NSRegularExpression(pattern: "@([\\p{L}0-9_]*)$", options: [])
-    private let commandRegex = try? NSRegularExpression(pattern: "^/([a-z]*)$", options: [])
-    
-    private let commands = [
-        "/msg", "/who", "/clear",
-        "/hug", "/slap", "/fav", "/unfav",
-        "/block", "/unblock"
-    ]

    /// Get autocomplete suggestions for current text
    func getSuggestions(for text: String, peers: [String], cursorPosition: Int) -> (suggestions: [String], range: NSRange?) {
@@ -73,26 +66,6 @@ final class AutocompleteService {
        return suggestions.isEmpty ? nil : (Array(suggestions), fullRange)
    }
    
-    private func getCommandSuggestions(_ text: String) -> ([String], NSRange)? {
-        guard let regex = commandRegex else { return nil }
-        
-        let nsText = text as NSString
-        let matches = regex.matches(in: text, options: [], range: NSRange(location: 0, length: nsText.length))
-        
-        guard let match = matches.last else { return nil }
-        
-        let fullRange = match.range(at: 0)
-        let captureRange = match.range(at: 1)
-        let prefix = nsText.substring(with: captureRange).lowercased()
-        
-        let suggestions = commands
-            .filter { $0.hasPrefix("/\(prefix)") }
-            .sorted()
-            .prefix(5)
-        
-        return suggestions.isEmpty ? nil : (Array(suggestions), fullRange)
-    }
-    
    private func needsArgument(command: String) -> Bool {
        switch command {
        case "/who", "/clear":
@@ -16,10 +16,19 @@ struct BLEAnnounceHandlerEnvironment {
    let now: () -> Date
    /// Noise public key already recorded for the peer, if any (registry read).
    let existingNoisePublicKey: (PeerID) -> Data?
+    /// Ed25519 key previously bound to this Noise identity by an authenticated
+    /// peer-state payload, if any (persistent identity-state read).
+    let authenticatedSigningPublicKey: (_ noisePublicKey: Data) -> Data?
    /// Verifies the packet signature against the announced signing key.
    let verifySignature: (_ packet: BitchatPacket, _ signingPublicKey: Data) -> Bool
    /// Direct link state for the peer (BLE-queue read).
    let linkState: (PeerID) -> (hasPeripheral: Bool, hasCentral: Bool)
+    /// Whether the link this packet arrived on is already bound to a
+    /// different peer ID (ingress-registry + BLE-queue read). Directness
+    /// rides on the unsigned TTL, so a replayed announce can look "direct"
+    /// on the replayer's link; that link must not shortcut an absent peer
+    /// into "connected".
+    let linkBoundToOtherPeer: (_ packet: BitchatPacket, _ peerID: PeerID) -> Bool
    /// Runs the registry mutation phase under the collections barrier.
    let withRegistryBarrier: (() -> Void) -> Void
    /// Upserts the verified announce into the peer registry.
@@ -124,17 +133,44 @@ final class BLEAnnounceHandler {
            hasSignature: hasSignature,
            signatureValid: signatureValid,
            existingNoisePublicKey: existingNoisePublicKey,
-            announcedNoisePublicKey: announcement.noisePublicKey
+            announcedNoisePublicKey: announcement.noisePublicKey,
+            authenticatedSigningPublicKey: env.authenticatedSigningPublicKey(
+                announcement.noisePublicKey
+            ),
+            announcedSigningPublicKey: announcement.signingPublicKey
        )
        if case .reject(.keyMismatch) = trustDecision {
            SecureLogger.warning("⚠️ Announce key mismatch for \(peerID.id.prefix(8))… — keeping unverified", category: .security)
        }
+        if case .reject(.authenticatedSigningKeyMismatch) = trustDecision {
+            SecureLogger.warning(
+                "⚠️ Announce signing-key replacement rejected for Noise-authenticated peer \(peerID.id.prefix(8))…",
+                category: .security
+            )
+        }
        let verifiedAnnounce = trustDecision.isVerified

        var isNewPeer = false
        var isReconnectedPeer = false
        let directLinkState = env.linkState(peerID)
        let isDirectAnnounce = packet.ttl == env.messageTTL
+        // A "direct" announce arriving on a link that another peer already
+        // owns is either a rotation heal or a replay with its TTL restored;
+        // both are ambiguous, so only the rebind (which containment-checks
+        // the claimed identity) may promote it — never this shortcut.
+        //
+        // Known limitation: denying the shortcut cannot prevent forged
+        // presence outright. A rebind that passes the containment checks
+        // promotes the claimed peer to connected — it must, or a legitimate
+        // rotation on an open link would read as disconnected — so a replay
+        // that wins the rebind (absent victim, cooldown clear) still forges
+        // presence. That residue is presence display only: DMs stay gated on
+        // canDeliverSecurely (no Noise session means retain + courier, see
+        // MessageRouter.sendPrivate). What this check buys: the ambiguous
+        // announce alone never flips presence — forging requires winning the
+        // containment-checked rebind (never steals an identity that owns a
+        // live link; at most one rebind per link per cooldown window).
+        let linkBoundToOtherPeer = isDirectAnnounce && env.linkBoundToOtherPeer(packet, peerID)

        env.withRegistryBarrier {
            let hasPeripheralConnection = directLinkState.hasPeripheral
@@ -152,7 +188,7 @@ final class BLEAnnounceHandler {
            let update = env.upsertVerifiedAnnounce(
                peerID,
                announcement,
-                isDirectAnnounce || hasPeripheralConnection || hasCentralSubscription,
+                hasPeripheralConnection || hasCentralSubscription || (isDirectAnnounce && !linkBoundToOtherPeer),
                now
            )
            isNewPeer = update.isNewPeer
@@ -56,6 +56,7 @@ enum BLEAnnounceTrustRejection: Equatable {
    case missingSignature
    case invalidSignature
    case keyMismatch
+    case authenticatedSigningKeyMismatch
 }

 enum BLEAnnounceTrustDecision: Equatable {
@@ -72,12 +73,19 @@ enum BLEAnnounceTrustPolicy {
        hasSignature: Bool,
        signatureValid: Bool,
        existingNoisePublicKey: Data?,
-        announcedNoisePublicKey: Data
+        announcedNoisePublicKey: Data,
+        authenticatedSigningPublicKey: Data? = nil,
+        announcedSigningPublicKey: Data? = nil
    ) -> BLEAnnounceTrustDecision {
        if let existingNoisePublicKey, existingNoisePublicKey != announcedNoisePublicKey {
            return .reject(.keyMismatch)
        }

+        if let authenticatedSigningPublicKey,
+           announcedSigningPublicKey != authenticatedSigningPublicKey {
+            return .reject(.authenticatedSigningKeyMismatch)
+        }
+
        guard hasSignature else {
            return .reject(.missingSignature)
        }
@@ -15,7 +15,10 @@ enum BLEFanoutSelector {
        excludedLinks: Set<BLEIngressLinkID> = [],
        peripheralPeerBindings: [String: PeerID] = [:],
        centralPeerBindings: [String: PeerID] = [:],
+        preferredPeripheralPerPeer: [PeerID: String] = [:],
+        collapseDuplicatePeerLinks: Bool = true,
        directedPeerHint: PeerID?,
+        requireDirectPeerLink: Bool = false,
        packetType: UInt8,
        messageID: String
    ) -> BLEFanoutSelection {
@@ -31,10 +34,14 @@ enum BLEFanoutSelector {
               to: directedPeerHint,
               links: rawAllowed,
               peripheralPeerBindings: peripheralPeerBindings,
-               centralPeerBindings: centralPeerBindings
+               centralPeerBindings: centralPeerBindings,
+               preferredPeripheralPerPeer: preferredPeripheralPerPeer
           ) {
            return directedSelection
        }
+        if directedPeerHint != nil, requireDirectPeerLink {
+            return BLEFanoutSelection(peripheralIDs: [], centralIDs: [])
+        }
        if let directedPeerHint,
           hasBoundLink(
               to: directedPeerHint,
@@ -46,11 +53,20 @@ enum BLEFanoutSelector {
            return BLEFanoutSelection(peripheralIDs: [], centralIDs: [])
        }

-        let allowed = collapseDuplicateLinksPerPeer(
+        // Direct announces are the packet that binds a link to its peer
+        // (BLEService's raw bind and verified rebind). Collapsing them per
+        // peer starves duplicate same-peer links of the announce they need to
+        // become bound — the duplicates then look "pre-announce" forever and
+        // every broadcast sprays down all of them. Announces are small and
+        // throttled, so they go on every live link.
+        let allowed = collapseDuplicatePeerLinks
+            ? collapseDuplicateLinksPerPeer(
                rawAllowed,
                peripheralPeerBindings: peripheralPeerBindings,
-            centralPeerBindings: centralPeerBindings
+                centralPeerBindings: centralPeerBindings,
+                preferredPeripheralPerPeer: preferredPeripheralPerPeer
            )
+            : rawAllowed

        guard shouldSubset(packetType: packetType, directedPeerHint: directedPeerHint) else {
            return BLEFanoutSelection(
@@ -97,7 +113,8 @@ enum BLEFanoutSelector {
        to peerID: PeerID,
        links: (peripheralIDs: [String], centralIDs: [String]),
        peripheralPeerBindings: [String: PeerID],
-        centralPeerBindings: [String: PeerID]
+        centralPeerBindings: [String: PeerID],
+        preferredPeripheralPerPeer: [PeerID: String]
    ) -> BLEFanoutSelection? {
        let directLinks = collapseDuplicateLinksPerPeer(
            (
@@ -105,7 +122,8 @@ enum BLEFanoutSelector {
                centralIDs: links.centralIDs.filter { centralPeerBindings[$0] == peerID }
            ),
            peripheralPeerBindings: peripheralPeerBindings,
-            centralPeerBindings: centralPeerBindings
+            centralPeerBindings: centralPeerBindings,
+            preferredPeripheralPerPeer: preferredPeripheralPerPeer
        )

        guard !directLinks.peripheralIDs.isEmpty || !directLinks.centralIDs.isEmpty else {
@@ -140,7 +158,8 @@ enum BLEFanoutSelector {
    private static func collapseDuplicateLinksPerPeer(
        _ links: (peripheralIDs: [String], centralIDs: [String]),
        peripheralPeerBindings: [String: PeerID],
-        centralPeerBindings: [String: PeerID]
+        centralPeerBindings: [String: PeerID],
+        preferredPeripheralPerPeer: [PeerID: String]
    ) -> (peripheralIDs: [String], centralIDs: [String]) {
        guard !peripheralPeerBindings.isEmpty || !centralPeerBindings.isEmpty else {
            return links
@@ -148,13 +167,30 @@ enum BLEFanoutSelector {

        var seenPeers = Set<PeerID>()
        var keptPeripheralIDs: [String] = []
+        // When a peer has several bound peripheral links (duplicate
+        // connections after a restore), collapse onto its preferred one (the
+        // most recently bound) instead of dictionary order — an arbitrary
+        // pick could route a peer's single collapsed copy down a stale link.
        for id in links.peripheralIDs {
-            if let peer = peripheralPeerBindings[id], !seenPeers.insert(peer).inserted {
-                continue
+            guard let peer = peripheralPeerBindings[id],
+                  preferredPeripheralPerPeer[peer] == id,
+                  seenPeers.insert(peer).inserted else { continue }
+            keptPeripheralIDs.append(id)
+        }
+        for id in links.peripheralIDs {
+            if let peer = peripheralPeerBindings[id] {
+                if preferredPeripheralPerPeer[peer] == id { continue }
+                if !seenPeers.insert(peer).inserted { continue }
            }
            keptPeripheralIDs.append(id)
        }

+        // Known limitation: centrals collapse in subscription order (oldest
+        // first) — there is no recency signal like the peripheral reverse
+        // map. A central-only peer with duplicate subscriptions rides the
+        // oldest one until the remote side (which owns those connections)
+        // consolidates on its next verified announce (bounded by its
+        // retirement cooldown).
        var keptCentralIDs: [String] = []
        for id in links.centralIDs {
            if let peer = centralPeerBindings[id], !seenPeers.insert(peer).inserted {
@@ -14,6 +14,10 @@ struct BLEFileTransferHandlerEnvironment {
    let localNickname: () -> String
    /// Snapshot of known peers keyed by ID (registry read).
    let peersSnapshot: () -> [PeerID: BLEPeerInfo]
+    /// Verifies a packet's signature against a candidate signing key (registry path).
+    let verifyPacketSignature: (_ packet: BitchatPacket, _ signingPublicKey: Data) -> Bool
+    /// Local signing key used to authenticate our own gossip-sync replays.
+    let localSigningPublicKey: () -> Data
    /// Resolves a display name from a verified packet signature for peers missing from the registry.
    let signedSenderDisplayName: (_ packet: BitchatPacket, _ peerID: PeerID) -> String?
    /// Tracks the broadcast file packet for gossip sync.
@@ -28,10 +32,85 @@ struct BLEFileTransferHandlerEnvironment {
        _ fallbackExtension: String?,
        _ defaultPrefix: String
    ) -> URL?
+    /// Resolves the durable receiver decision for a stable private-media ID.
+    let privateMediaReceiptState: (
+        _ messageID: String
+    ) -> BLEPrivateMediaReceiptState
+    /// Atomically records a stable private-media ID after the payload save.
+    let commitPrivateMediaFile: (_ messageID: String, _ storedURL: URL) -> Bool
+    /// Rolls back a saved payload when its durable receipt commit fails.
+    let removeIncomingFile: (_ storedURL: URL) -> Void
+    /// Releases the allocator's save-to-UI ownership guard after synchronous
+    /// conversation insertion has completed.
+    let finishIncomingFileDelivery: (_ storedURL: URL) -> Void
+    /// Checks the authenticated sender before any private-media disk work.
+    let isPrivateMediaSenderBlocked: (PeerID) -> Bool
    /// Updates the registry last-seen timestamp for the peer (async barrier write).
    let updatePeerLastSeen: (PeerID) -> Void
-    /// Delivers `.messageReceived` to the UI as one main-actor hop.
-    let deliverMessage: (BitchatMessage) -> Void
+    /// Acknowledges stable private media only after its synchronous
+    /// conversation delivery has completed.
+    let acknowledgePrivateMedia: (_ messageID: String, _ peerID: PeerID) -> Void
+    /// Delivers `.messageReceived` as one main-actor hop while
+    /// `shouldDeliver` remains true before and after the synchronous sink.
+    /// The completion authorizes the stable-media ACK. Finalization runs after
+    /// every delivery attempt, including rejection, so allocator ownership
+    /// cannot leak indefinitely.
+    let deliverMessage: (
+        _ message: BitchatMessage,
+        _ shouldDeliver: @escaping () -> Bool,
+        _ completion: @escaping () -> Void,
+        _ finalization: @escaping (TransportEventDeliveryOutcome) -> Void
+    ) -> Void
+}
+
+/// Process-lifetime reservation cache for stable private-media IDs.
+///
+/// The first arrival reserves its ID before quota enforcement. Concurrent
+/// arrivals remain coalesced in memory, while accepted state is resolved from
+/// the durable ID-to-file ledger so it survives relaunch and becomes retryable
+/// if quota cleanup removed the file.
+private final class PrivateMediaArrivalDeduplicator {
+    enum Reservation {
+        case reserved
+        case pending
+        case accepted(URL)
+        case tombstoned
+        case unavailable
+    }
+
+    private let lock = NSLock()
+    private var pending: Set<String> = []
+
+    func reserve(
+        _ messageID: String,
+        receiptState: () -> BLEPrivateMediaReceiptState
+    ) -> Reservation {
+        lock.lock()
+        defer { lock.unlock() }
+        if pending.contains(messageID) {
+            return .pending
+        }
+
+        switch receiptState() {
+        case .accepted(let existingURL):
+            return .accepted(existingURL)
+        case .tombstoned:
+            return .tombstoned
+        case .unavailable:
+            return .unavailable
+        case .absent:
+            break
+        }
+
+        pending.insert(messageID)
+        return .reserved
+    }
+
+    func finish(_ messageID: String) {
+        lock.lock()
+        defer { lock.unlock() }
+        pending.remove(messageID)
+    }
 }

 /// Orchestrates inbound file transfers: self-echo policy, sender display-name
@@ -39,54 +118,202 @@ struct BLEFileTransferHandlerEnvironment {
 /// and UI delivery.
 final class BLEFileTransferHandler {
    private let environment: BLEFileTransferHandlerEnvironment
+    private let privateMediaArrivals = PrivateMediaArrivalDeduplicator()

    init(environment: BLEFileTransferHandlerEnvironment) {
        self.environment = environment
    }

-    /// `payloadLimit` defaults to the Bluetooth cap; Wi-Fi bulk deliveries
-    /// pass the ceiling that was enforced against the accepted offer.
-    func handle(_ packet: BitchatPacket, from peerID: PeerID, payloadLimit: Int = FileTransferLimits.maxPayloadBytes) {
+    /// Returns `false` when the raw packet fails sender authentication (or is
+    /// a live self-echo) and must not be relayed onward. Authentication runs
+    /// before the routing decision, so a forged directed packet cannot use a
+    /// node that is not its recipient as an unsigned forwarding hop.
+    @discardableResult
+    func handle(_ packet: BitchatPacket, from peerID: PeerID) -> Bool {
        let env = environment
-        if BLEFileTransferPolicy.isSelfEcho(packet: packet, from: peerID, localPeerID: env.localPeerID()) { return }
-
+        let localPeerID = env.localPeerID()
        let peersSnapshot = env.peersSnapshot()
-        guard let senderNickname = BLEPeerSenderDisplayName.resolveKnownPeer(
-            peerID: peerID,
-            localPeerID: env.localPeerID(),
-            localNickname: env.localNickname(),
+
+        guard let senderNickname = authenticatedRawSenderNickname(
+            packet: packet,
+            from: peerID,
            peers: peersSnapshot,
-            allowConnectedUnverified: true
-        ) ?? env.signedSenderDisplayName(packet, peerID) else {
-            SecureLogger.warning("🚫 Dropping file transfer from unverified or unknown peer \(peerID.id.prefix(8))…", category: .security)
-            return
+            env: env
+        ) else {
+            SecureLogger.warning("🚫 Dropping raw file transfer with missing/invalid signature from \(peerID.id.prefix(8))…", category: .security)
+            return false
        }

-        guard let deliveryPlan = BLEFileTransferPolicy.deliveryPlan(packet: packet, localPeerID: env.localPeerID()) else {
-            return
+        if BLEFileTransferPolicy.isSelfEcho(packet: packet, from: peerID, localPeerID: localPeerID) {
+            return false
        }
+
+        guard let deliveryPlan = BLEFileTransferPolicy.deliveryPlan(packet: packet, localPeerID: localPeerID) else {
+            return true
+        }
+
        if deliveryPlan.shouldTrackForSync {
            env.trackPacketSeen(packet)
        }

+        _ = storeIncomingPayload(
+            packet.payload,
+            from: peerID,
+            senderNickname: senderNickname,
+            timestamp: Date(timeIntervalSince1970: Double(packet.timestamp) / 1000),
+            isPrivate: deliveryPlan.isPrivateMessage,
+            usesDurableReceipts: false,
+            env: env
+        )
+        // Once authenticated, a local decode/quota/save failure is not proof
+        // that downstream nodes should be denied the valid signed packet.
+        return true
+    }
+
+    /// Accepts a file packet only after it has been authenticated and
+    /// decrypted by the peer's Noise session. The inner packet deliberately
+    /// has no redundant signature: Noise supplies sender authentication and
+    /// confidentiality, while this handler retains the same validation,
+    /// quota, persistence, and UI-delivery behavior as public files.
+    @discardableResult
+    func handlePrivatePayload(_ payload: Data, from peerID: PeerID, timestamp: Date) -> Bool {
+        let env = environment
+        let peers = env.peersSnapshot()
+        let senderNickname = BLEPeerSenderDisplayName.resolveKnownPeer(
+            peerID: peerID,
+            localPeerID: env.localPeerID(),
+            localNickname: env.localNickname(),
+            peers: peers,
+            allowConnectedUnverified: true
+        ) ?? BLEPeerSenderDisplayName.anonymousNickname(for: peerID)
+
+        return storeIncomingPayload(
+            payload,
+            from: peerID,
+            senderNickname: senderNickname,
+            timestamp: timestamp,
+            isPrivate: true,
+            // Every authenticated Noise private-file keeps the stable ID/ACK
+            // contract introduced with capability bit 8. Bit 9 advertises
+            // sender-side automatic retry support; it must not downgrade
+            // prior iOS clients to random IDs or single-check delivery.
+            usesDurableReceipts: true,
+            env: env
+        )
+    }
+
+    private func storeIncomingPayload(
+        _ payload: Data,
+        from peerID: PeerID,
+        senderNickname: String,
+        timestamp: Date,
+        isPrivate: Bool,
+        usesDurableReceipts: Bool,
+        env: BLEFileTransferHandlerEnvironment
+    ) -> Bool {
+
+        let localPeerID = env.localPeerID()
        let filePacket: BitchatFilePacket
        let mime: MimeType
-        switch BLEIncomingFileValidator.validate(payload: packet.payload, limit: payloadLimit) {
+        switch BLEIncomingFileValidator.validate(payload: payload) {
        case .success(let acceptance):
            filePacket = acceptance.filePacket
            mime = acceptance.mime
        case .failure(.malformedPayload):
            SecureLogger.error("❌ Failed to decode file transfer payload", category: .session)
-            return
+            return false
        case .failure(.payloadTooLarge(let bytes)):
            SecureLogger.warning("🚫 Dropping file transfer exceeding size cap (\(bytes) bytes)", category: .security)
-            return
+            return false
        case .failure(.unsupportedMime(let mimeType, let bytes)):
            SecureLogger.warning("🚫 MIME REJECT: '\(mimeType ?? "<empty>")' not supported. Size=\(bytes)b from \(peerID.id.prefix(8))...", category: .security)
-            return
+            return false
        case .failure(.magicMismatch(let mime, let bytes, let prefixHex)):
            SecureLogger.warning("🚫 MAGIC REJECT: MIME='\(mime)' size=\(bytes)b prefix=[\(prefixHex)] from \(peerID.id.prefix(8))...", category: .security)
-            return
+            return false
+        }
+
+        if isPrivate, env.isPrivateMediaSenderBlocked(peerID) {
+            SecureLogger.debug(
+                "🚫 Dropping private media from blocked peer \(peerID.id.prefix(8))… before disk write",
+                category: .security
+            )
+            return true
+        }
+
+        let messageID = usesDurableReceipts
+            ? PrivateMediaMessageIdentity.stableID(
+                for: filePacket,
+                senderPeerID: peerID,
+                recipientPeerID: localPeerID
+            )
+            : nil
+        if let messageID {
+            switch privateMediaArrivals.reserve(
+                messageID,
+                receiptState: { env.privateMediaReceiptState(messageID) }
+            ) {
+            case .reserved:
+                break
+            case .pending:
+                // The first arrival has not reached durable storage yet.
+                // Coalesce this retry without ACKing so a failed first save
+                // remains retryable by the sender.
+                SecureLogger.debug(
+                    "📁 Coalesced in-flight private media id=\(messageID.prefix(12))… from \(peerID.id.prefix(8))…",
+                    category: .session
+                )
+                return true
+            case .accepted(let existingFile):
+                env.updatePeerLastSeen(peerID)
+                let message = incomingMessage(
+                    messageID: messageID,
+                    senderNickname: senderNickname,
+                    timestamp: timestamp,
+                    isPrivate: true,
+                    peerID: peerID,
+                    destination: existingFile,
+                    category: storedMediaCategory(
+                        for: existingFile,
+                        fallback: mime.category
+                    ),
+                    env: env
+                )
+                SecureLogger.debug(
+                    "📁 Restored durable private media duplicate id=\(messageID.prefix(12))… from \(peerID.id.prefix(8))… -> \(existingFile.lastPathComponent)",
+                    category: .session
+                )
+                deliverStableMessage(
+                    message,
+                    messageID: messageID,
+                    peerID: peerID,
+                    expectedURL: existingFile,
+                    env: env
+                )
+                return true
+            case .tombstoned:
+                // Explicit deletion is a durable terminal receiver decision.
+                env.updatePeerLastSeen(peerID)
+                env.acknowledgePrivateMedia(messageID, peerID)
+                SecureLogger.debug(
+                    "📁 Dropped explicitly deleted private media id=\(messageID.prefix(12))… from \(peerID.id.prefix(8))…",
+                    category: .session
+                )
+                return true
+            case .unavailable:
+                // Never turn an unreadable ledger into an empty ledger. The
+                // sender can retry after the transient storage failure clears.
+                SecureLogger.warning(
+                    "📁 Withholding private media id=\(messageID.prefix(12))… while durable receipt state is unavailable",
+                    category: .session
+                )
+                return true
+            }
+        }
+        defer {
+            if let messageID {
+                privateMediaArrivals.finish(messageID)
+            }
        }

        // BCH-01-002: Enforce storage quota before saving
@@ -99,27 +326,175 @@ final class BLEFileTransferHandler {
            mime.defaultExtension,
            mime.category.rawValue
        ) else {
-            return
+            return false
        }

-        if deliveryPlan.isPrivateMessage {
+        if let messageID,
+           !env.commitPrivateMediaFile(messageID, destination) {
+            // A payload without its durable ID mapping cannot safely suppress
+            // a retry after relaunch. Roll it back and withhold UI/ACK.
+            env.removeIncomingFile(destination)
+            return false
+        }
+
+        if isPrivate {
            env.updatePeerLastSeen(peerID)
        }

-        let ts = Date(timeIntervalSince1970: Double(packet.timestamp) / 1000)
-        let message = BitchatMessage(
-            sender: senderNickname,
-            content: "\(mime.category.messagePrefix)\(destination.lastPathComponent)",
-            timestamp: ts,
-            isRelay: false,
-            originalSender: nil,
-            isPrivate: deliveryPlan.isPrivateMessage,
-            recipientNickname: nil,
-            senderPeerID: peerID
+        let message = incomingMessage(
+            messageID: messageID,
+            senderNickname: senderNickname,
+            timestamp: timestamp,
+            isPrivate: isPrivate,
+            peerID: peerID,
+            destination: destination,
+            category: mime.category,
+            env: env
        )

        SecureLogger.debug("📁 Stored incoming media from \(peerID.id.prefix(8))… -> \(destination.lastPathComponent)", category: .session)

-        env.deliverMessage(message)
+        if let messageID {
+            deliverStableMessage(
+                message,
+                messageID: messageID,
+                peerID: peerID,
+                expectedURL: destination,
+                env: env
+            )
+        } else {
+            env.deliverMessage(
+                message,
+                { true },
+                {},
+                { outcome in
+                    if outcome == .rejected {
+                        // Raw media has no durable receipt that can redeliver
+                        // it later. Do not leave a newly saved, UI-unowned file
+                        // available for a stale fallback path to misidentify.
+                        env.removeIncomingFile(destination)
+                    } else {
+                        // Plain delegates are invoked without synchronous
+                        // insertion confirmation. Preserve the payload for
+                        // that supported delivery path.
+                        env.finishIncomingFileDelivery(destination)
+                    }
+                }
+            )
+        }
+        return true
+    }
+
+    private func deliverStableMessage(
+        _ message: BitchatMessage,
+        messageID: String,
+        peerID: PeerID,
+        expectedURL: URL,
+        env: BLEFileTransferHandlerEnvironment
+    ) {
+        env.deliverMessage(
+            message,
+            {
+                guard case .accepted(let resolvedURL) =
+                        env.privateMediaReceiptState(messageID) else {
+                    return false
+                }
+                return resolvedURL.standardizedFileURL
+                    == expectedURL.standardizedFileURL
+            },
+            {
+                env.acknowledgePrivateMedia(messageID, peerID)
+            },
+            { _ in
+                env.finishIncomingFileDelivery(expectedURL)
+            }
+        )
+    }
+
+    private func incomingMessage(
+        messageID: String?,
+        senderNickname: String,
+        timestamp: Date,
+        isPrivate: Bool,
+        peerID: PeerID,
+        destination: URL,
+        category: MimeType.Category,
+        env: BLEFileTransferHandlerEnvironment
+    ) -> BitchatMessage {
+        BitchatMessage(
+            id: messageID,
+            sender: senderNickname,
+            content: "\(category.messagePrefix)\(destination.lastPathComponent)",
+            timestamp: timestamp,
+            isRelay: false,
+            originalSender: nil,
+            isPrivate: isPrivate,
+            recipientNickname: nil,
+            senderPeerID: peerID,
+            // Received messages need an explicit status: BitchatMessage
+            // defaults private messages to .sending, which media views render
+            // as an in-flight send.
+            deliveryStatus: isPrivate
+                ? .delivered(to: env.localNickname(), at: timestamp)
+                : nil
+        )
+    }
+
+    /// The durable URL is authoritative during reconstruction. A sender that
+    /// reuses a stable filename with a different MIME type must not change how
+    /// the already-stored payload renders.
+    private func storedMediaCategory(
+        for url: URL,
+        fallback: MimeType.Category
+    ) -> MimeType.Category {
+        let mediaDirectory = url
+            .deletingLastPathComponent()
+            .deletingLastPathComponent()
+            .lastPathComponent
+        switch mediaDirectory {
+        case MimeType.Category.audio.mediaDir:
+            return .audio
+        case MimeType.Category.image.mediaDir:
+            return .image
+        case MimeType.Category.file.mediaDir:
+            return .file
+        default:
+            return fallback
+        }
+    }
+
+    /// Every remaining raw file transfer is signed, regardless of whether it
+    /// is broadcast, addressed to us, or merely passing through. Registry
+    /// signing keys are preferred; persisted identities cover peers that have
+    /// rotated or are not currently present in the registry.
+    private func authenticatedRawSenderNickname(
+        packet: BitchatPacket,
+        from peerID: PeerID,
+        peers: [PeerID: BLEPeerInfo],
+        env: BLEFileTransferHandlerEnvironment
+    ) -> String? {
+        guard packet.signature != nil else { return nil }
+
+        let localPeerID = env.localPeerID()
+        let candidateKey = peerID == localPeerID
+            ? env.localSigningPublicKey()
+            : peers[peerID]?.signingPublicKey
+        let verifiedWithKnownKey = candidateKey.map {
+            env.verifyPacketSignature(packet, $0)
+        } ?? false
+        let signedDisplayName = verifiedWithKnownKey
+            ? nil
+            : env.signedSenderDisplayName(packet, peerID)
+        guard verifiedWithKnownKey || signedDisplayName != nil else { return nil }
+
+        return BLEPeerSenderDisplayName.resolveKnownPeer(
+            peerID: peerID,
+            localPeerID: localPeerID,
+            localNickname: env.localNickname(),
+            peers: peers,
+            // The packet signature authenticates the announced peer; the old
+            // connected-but-unsigned leniency is not involved.
+            allowConnectedUnverified: true
+        ) ?? signedDisplayName ?? BLEPeerSenderDisplayName.anonymousNickname(for: peerID)
    }
 }
@@ -42,17 +42,12 @@ enum BLEIncomingFileRejection: Error, Equatable {
 }

 enum BLEIncomingFileValidator {
-    /// `limit` defaults to the Bluetooth payload cap; Wi-Fi bulk deliveries
-    /// pass the ceiling enforced against the accepted offer.
-    static func validate(
-        payload: Data,
-        limit: Int = FileTransferLimits.maxPayloadBytes
-    ) -> Result<BLEIncomingFileAcceptance, BLEIncomingFileRejection> {
-        guard let filePacket = BitchatFilePacket.decode(payload, limit: limit) else {
+    static func validate(payload: Data) -> Result<BLEIncomingFileAcceptance, BLEIncomingFileRejection> {
+        guard let filePacket = BitchatFilePacket.decode(payload) else {
            return .failure(.malformedPayload)
        }

-        guard FileTransferLimits.isValidPayload(filePacket.content.count, limit: limit) else {
+        guard FileTransferLimits.isValidPayload(filePacket.content.count) else {
            return .failure(.payloadTooLarge(bytes: filePacket.content.count))
        }

@@ -61,7 +61,6 @@ struct BLEFragmentAssemblyBuffer {
    }

    private struct Metadata {
-        let type: UInt8
        let total: Int
        let timestamp: Date
        let isBroadcast: Bool
@@ -150,7 +149,6 @@ struct BLEFragmentAssemblyBuffer {

        fragmentsByKey[header.key] = [:]
        metadataByKey[header.key] = Metadata(
-            type: header.originalType,
            total: header.total,
            timestamp: now,
            isBroadcast: header.isBroadcastFragment,
@@ -203,8 +201,11 @@ struct BLEFragmentAssemblyBuffer {
    }

    private static func assemblyLimit(for originalType: UInt8) -> Int {
-        if originalType == MessageType.fileTransfer.rawValue {
+        if originalType == MessageType.fileTransfer.rawValue
+            || originalType == MessageType.noiseEncrypted.rawValue {
            // Allow headroom for TLV metadata and binary framing overhead.
+            // A large noiseEncrypted packet can be an E2E-encrypted private
+            // file; its authenticated plaintext is validated after decrypt.
            return FileTransferLimits.maxFramedFileBytes
        }

@@ -33,13 +33,21 @@ final class BLEFragmentHandler {

    func handle(_ packet: BitchatPacket, from peerID: PeerID) {
        let env = environment
-        // Don't process our own fragments
+        guard let header = BLEFragmentHeader(packet: packet) else { return }
+
+        // Sync replay legitimately hands us our own fragments back (the RSR
+        // ttl=0 restore path): after a relaunch the fragment store starts
+        // empty, so our sync filter doesn't cover them and peers re-offer
+        // them. Record them as seen — the next round's filter then covers
+        // them and the redelivery stops — but skip assembly: we authored
+        // the original, there is nothing to reassemble.
        if peerID == env.localPeerID() {
+            if header.isBroadcastFragment {
+                env.trackPacketSeen(packet)
+            }
            return
        }

-        guard let header = BLEFragmentHeader(packet: packet) else { return }
-
        if header.isBroadcastFragment {
            env.trackPacketSeen(packet)
        }
@@ -2,17 +2,271 @@ import BitLogger
 import BitFoundation
 import Foundation

-struct BLEIncomingFileStore {
-    private static let quotaBytes: Int64 = 100 * 1024 * 1024
+struct PanicRecoveryIntent {
+    let fileMarkerEstablished: Bool
+    let externalMarkerEstablished: Bool

-    private let fileManager: FileManager
+    var hasDurableMarker: Bool {
+        fileMarkerEstablished || externalMarkerEstablished
+    }
+}
+
+/// Small, dependency-injectable transaction surface used by ChatViewModel.
+/// Production persists the same intent in two independent locations before
+/// any application state is erased. Tests can inject an ephemeral operation
+/// set without touching the developer's Application Support directory.
+struct PanicRecoveryOperations {
+    let isPending: () throws -> Bool
+    let begin: () -> PanicRecoveryIntent
+    let wipeMedia: (PanicRecoveryIntent) throws -> Void
+    let complete: () throws -> Void
+
+    static func ephemeral(
+        wipeMedia: @escaping () throws -> Void = {}
+    ) -> PanicRecoveryOperations {
+        PanicRecoveryOperations(
+            isPending: { false },
+            begin: {
+                PanicRecoveryIntent(
+                    fileMarkerEstablished: false,
+                    externalMarkerEstablished: false
+                )
+            },
+            wipeMedia: { _ in try wipeMedia() },
+            complete: {}
+        )
+    }
+
+    static func live(
+        fileStore: BLEIncomingFileStore = BLEIncomingFileStore(),
+        defaults: UserDefaults = .standard
+    ) -> PanicRecoveryOperations {
+        let defaultsKey = "bitchat.panicResetPending"
+        return PanicRecoveryOperations(
+            isPending: {
+                if defaults.bool(forKey: defaultsKey) {
+                    return true
+                }
+                return try fileStore.isPanicRecoveryPending()
+            },
+            begin: {
+                defaults.set(true, forKey: defaultsKey)
+                let externalMarkerEstablished =
+                    defaults.synchronize()
+                    && defaults.bool(forKey: defaultsKey)
+
+                let fileMarkerEstablished: Bool
+                do {
+                    try fileStore.markPanicRecoveryPending()
+                    fileMarkerEstablished = true
+                } catch {
+                    fileMarkerEstablished = false
+                    SecureLogger.error(
+                        "Failed to persist file panic-recovery marker: \(error)",
+                        category: .security
+                    )
+                }
+
+                return PanicRecoveryIntent(
+                    fileMarkerEstablished: fileMarkerEstablished,
+                    externalMarkerEstablished: externalMarkerEstablished
+                )
+            },
+            wipeMedia: { intent in
+                try fileStore.panicWipe(
+                    hasDurablePendingMarker: intent.hasDurableMarker
+                )
+            },
+            complete: {
+                // Keep the independent defaults latch until the file marker
+                // has definitely cleared. Any failure therefore remains
+                // visible to the next launch.
+                try fileStore.completePanicRecovery()
+                defaults.removeObject(forKey: defaultsKey)
+                guard defaults.synchronize(),
+                      !defaults.bool(forKey: defaultsKey) else {
+                    throw BLEIncomingFileStore.PanicRecoveryError
+                        .externalMarkerCommitFailed
+                }
+            }
+        )
+    }
+}
+
+struct BLEIncomingFileStore: @unchecked Sendable {
+    enum PanicRecoveryError: Error {
+        case externalMarkerCommitFailed
+        case markerWriteFailed(Error)
+        case markerWriteAndMediaWipeFailed(
+            markerError: Error,
+            mediaError: Error
+        )
+    }
+
+    struct PrivateMediaDeletionReservation: Sendable {
+        fileprivate let id: UUID
+    }
+
+    private final class PayloadCoordination: @unchecked Sendable {
+        let lock = NSLock()
+        var pendingDeliveryPaths: Set<String> = []
+        var deletionReservations: [UUID: Set<String>] = [:]
+    }
+
+    private static let defaultQuotaBytes: Int64 = 100 * 1024 * 1024
+    /// Kept outside `files/` so deleting the media tree cannot erase the
+    /// fail-closed startup decision before the full panic has committed.
+    private static let panicRecoveryPendingMarkerFileName =
+        ".panic-recovery-pending"
+    /// Compatibility with a short-lived development build that used the
+    /// media-specific name for the same full-transaction latch.
+    private static let legacyPanicRecoveryPendingMarkerFileName =
+        ".panic-media-wipe-pending"
+    private static let mediaSubdirectories = [
+        "voicenotes/incoming",
+        "voicenotes/outgoing",
+        "images/incoming",
+        "images/outgoing",
+        "files/incoming",
+        "files/outgoing"
+    ]
+    /// Name prefix of in-flight live voice captures (progressively written by
+    /// `ChatLiveVoiceCoordinator`). Quota eviction skips them by pattern —
+    /// deleting one mid-stream unlinks the inode under an open `FileHandle`
+    /// and kills playback — and the coordinator's startup sweep deletes any
+    /// orphans a previous session left behind.
+    static let liveCapturePrefix = "voice_live_"
+
+    /// Exposed so callers that write progressively into the store's
+    /// directories (live voice captures) share the same file manager.
+    let fileManager: FileManager
    private let baseDirectory: URL?
    private let dateProvider: () -> Date
+    private let panicMarkerWriter: (Data, URL) throws -> Void
+    private let quotaBytes: Int64
+    private let privateMediaReceipts: BLEPrivateMediaReceiptStore
+    private let payloadCoordination: PayloadCoordination

-    init(fileManager: FileManager = .default, baseDirectory: URL? = nil, dateProvider: @escaping () -> Date = Date.init) {
+    init(
+        fileManager: FileManager = .default,
+        baseDirectory: URL? = nil,
+        dateProvider: @escaping () -> Date = Date.init,
+        panicMarkerWriter: @escaping (Data, URL) throws -> Void = {
+            try $0.write(to: $1, options: .atomic)
+        },
+        quotaBytes: Int64 = Self.defaultQuotaBytes
+    ) {
        self.fileManager = fileManager
        self.baseDirectory = baseDirectory
        self.dateProvider = dateProvider
+        self.panicMarkerWriter = panicMarkerWriter
+        self.quotaBytes = max(0, quotaBytes)
+        self.privateMediaReceipts = BLEPrivateMediaReceiptStore(
+            fileManager: fileManager,
+            baseDirectory: baseDirectory,
+            now: dateProvider
+        )
+        self.payloadCoordination = PayloadCoordination()
+    }
+
+    /// Panic-wipe every managed incoming and outgoing media artifact before
+    /// returning. Recreating the directory tree keeps later capture/receive
+    /// paths usable without allowing a detached cleanup task to race them.
+    ///
+    /// Marker persistence and deletion are deliberately separate error
+    /// domains: even when both durable marker channels fail, deletion is
+    /// still attempted before this method reports the marker failure.
+    func panicWipe(
+        hasDurablePendingMarker: Bool = false
+    ) throws {
+        // The receipt index caches tombstones as well as accepted payloads,
+        // while payload coordination retains save/delete reservations. Always
+        // invalidate both on return, including partial-failure paths, so no
+        // pre-panic receiver decision survives after identity reset.
+        defer {
+            privateMediaReceipts.resetForPanic()
+            payloadCoordination.lock.lock()
+            payloadCoordination.pendingDeliveryPaths.removeAll(
+                keepingCapacity: false
+            )
+            payloadCoordination.deletionReservations.removeAll(
+                keepingCapacity: false
+            )
+            payloadCoordination.lock.unlock()
+        }
+
+        let markerError: Error?
+        do {
+            try markPanicRecoveryPending()
+            markerError = nil
+        } catch {
+            markerError = error
+            SecureLogger.error(
+                "Could not persist file panic-recovery marker; attempting media deletion anyway: \(error)",
+                category: .security
+            )
+        }
+
+        do {
+            let filesDirectory = try rootDirectory()
+                .appendingPathComponent("files", isDirectory: true)
+            if fileManager.fileExists(atPath: filesDirectory.path) {
+                try fileManager.removeItem(at: filesDirectory)
+            }
+            for subdirectory in Self.mediaSubdirectories {
+                try fileManager.createDirectory(
+                    at: filesDirectory.appendingPathComponent(
+                        subdirectory,
+                        isDirectory: true
+                    ),
+                    withIntermediateDirectories: true,
+                    attributes: nil
+                )
+            }
+        } catch {
+            if let markerError {
+                throw PanicRecoveryError.markerWriteAndMediaWipeFailed(
+                    markerError: markerError,
+                    mediaError: error
+                )
+            }
+            throw error
+        }
+
+        if let markerError, !hasDurablePendingMarker {
+            throw PanicRecoveryError.markerWriteFailed(markerError)
+        }
+    }
+
+    func markPanicRecoveryPending() throws {
+        let markerURL = try panicRecoveryPendingMarkerURL()
+        try fileManager.createDirectory(
+            at: markerURL.deletingLastPathComponent(),
+            withIntermediateDirectories: true,
+            attributes: nil
+        )
+        try panicMarkerWriter(Data([1]), markerURL)
+    }
+
+    func isPanicRecoveryPending() throws -> Bool {
+        try panicRecoveryMarkerURLs().contains {
+            fileManager.fileExists(atPath: $0.path)
+        }
+    }
+
+    func completePanicRecovery() throws {
+        for markerURL in try panicRecoveryMarkerURLs()
+        where fileManager.fileExists(atPath: markerURL.path) {
+            try fileManager.removeItem(at: markerURL)
+        }
+    }
+
+    /// Resolves (and creates) an incoming-media directory for callers that
+    /// write progressively instead of via `save` (live voice captures).
+    func incomingDirectory(subdirectory: String) throws -> URL {
+        let directory = try filesDirectory().appendingPathComponent(subdirectory, isDirectory: true)
+        try fileManager.createDirectory(at: directory, withIntermediateDirectories: true, attributes: nil)
+        return directory
    }

    func save(
@@ -22,6 +276,9 @@ struct BLEIncomingFileStore {
        fallbackExtension: String?,
        defaultPrefix: String
    ) -> URL? {
+        payloadCoordination.lock.lock()
+        defer { payloadCoordination.lock.unlock() }
+
        do {
            let base = try filesDirectory().appendingPathComponent(subdirectory, isDirectory: true)
            try fileManager.createDirectory(at: base, withIntermediateDirectories: true, attributes: nil)
@@ -30,8 +287,26 @@ struct BLEIncomingFileStore {
                defaultName: "\(defaultPrefix)_\(Self.timestampString(from: dateProvider()))",
                fallbackExtension: fallbackExtension
            )
-            let destination = uniqueFileURL(in: base, fileName: sanitized)
+            let reservedPaths = privateMediaReceipts.reservedPayloadPaths()
+            let deletionPaths = payloadCoordination
+                .deletionReservations.values.reduce(into: Set<String>()) {
+                    $0.formUnion($1)
+                }
+            let allocationReservations = deletionPaths.union(
+                payloadCoordination.pendingDeliveryPaths
+            )
+            let destination = uniqueFileURL(
+                in: base,
+                fileName: sanitized,
+                reservedPaths: (reservedPaths ?? []).union(
+                    allocationReservations
+                ),
+                forceRandomizedName: reservedPaths == nil
+            )
            try data.write(to: destination, options: .atomic)
+            payloadCoordination.pendingDeliveryPaths.insert(
+                destination.standardizedFileURL.path
+            )
            return destination
        } catch {
            SecureLogger.error("❌ Failed to persist incoming media: \(error)", category: .session)
@@ -39,7 +314,111 @@ struct BLEIncomingFileStore {
        }
    }

+    func privateMediaReceiptState(
+        messageID: String
+    ) -> BLEPrivateMediaReceiptState {
+        privateMediaReceipts.state(for: messageID)
+    }
+
+    func commitPrivateMediaFile(
+        messageID: String,
+        storedURL: URL
+    ) -> Bool {
+        privateMediaReceipts.commitAccepted(
+            messageID: messageID,
+            storedURL: storedURL
+        )
+    }
+
+    /// Reserves every receipt/UI path before the asynchronous deletion
+    /// barrier. Allocation and reservation share one lock, so either an
+    /// in-flight raw arrival is observed and deletion fails closed, or the
+    /// arrival is forced onto a different filename.
+    func reservePrivateMediaDeletion(
+        messageIDs: [String],
+        payloadRelativePaths: [String: String]
+    ) -> PrivateMediaDeletionReservation? {
+        payloadCoordination.lock.lock()
+        defer { payloadCoordination.lock.unlock() }
+
+        guard let paths = privateMediaReceipts
+            .prospectiveDeletionPayloadPaths(
+                messageIDs: messageIDs,
+                payloadRelativePaths: payloadRelativePaths
+            ),
+        paths.isDisjoint(
+            with: payloadCoordination.pendingDeliveryPaths
+        ) else {
+            return nil
+        }
+
+        let reservation = PrivateMediaDeletionReservation(id: UUID())
+        payloadCoordination.deletionReservations[reservation.id] = paths
+        return reservation
+    }
+
+    func commitPrivateMediaDeletion(
+        reservation: PrivateMediaDeletionReservation,
+        messageIDs: [String],
+        payloadRelativePaths: [String: String],
+        protectedPayloadRelativePaths: Set<String>
+    ) -> Bool {
+        payloadCoordination.lock.lock()
+        defer {
+            payloadCoordination.deletionReservations.removeValue(
+                forKey: reservation.id
+            )
+            payloadCoordination.lock.unlock()
+        }
+        guard payloadCoordination.deletionReservations[reservation.id] != nil
+        else {
+            return false
+        }
+        return privateMediaReceipts.recordDeleted(
+            messageIDs: messageIDs,
+            payloadRelativePaths: payloadRelativePaths,
+            protectedPayloadRelativePaths: protectedPayloadRelativePaths
+        )
+    }
+
+    /// Releases the short window between disk save and synchronous
+    /// conversation insertion. Before this callback, a deletion transaction
+    /// may not infer ownership from a stale bubble that names the same path.
+    func finishIncomingFileDelivery(at storedURL: URL) {
+        payloadCoordination.lock.lock()
+        defer { payloadCoordination.lock.unlock() }
+        payloadCoordination.pendingDeliveryPaths.remove(
+            storedURL.standardizedFileURL.path
+        )
+    }
+
+    /// Best-effort rollback for a payload whose durable receipt commit failed.
+    func removeIncomingFile(at storedURL: URL) {
+        payloadCoordination.lock.lock()
+        defer { payloadCoordination.lock.unlock() }
+        payloadCoordination.pendingDeliveryPaths.remove(
+            storedURL.standardizedFileURL.path
+        )
+        guard isURLInsideFilesDirectory(storedURL) else { return }
+        do {
+            try fileManager.removeItem(at: storedURL)
+        } catch {
+            SecureLogger.warning(
+                "⚠️ Failed to roll back uncommitted incoming media: \(error)",
+                category: .session
+            )
+        }
+    }
+
+    /// Frees least-recently-modified incoming files until `reservingBytes`
+    /// fits under the quota. Files named `voice_live_*` (in-flight live
+    /// captures) are never evicted regardless of who triggers enforcement —
+    /// a finalized transfer can arrive at quota while a burst is still
+    /// streaming — but they still count toward usage.
    func enforceQuota(reservingBytes: Int) {
+        payloadCoordination.lock.lock()
+        defer { payloadCoordination.lock.unlock() }
+
        do {
            let base = try filesDirectory()
            let incomingDirs = [
@@ -65,13 +444,26 @@ struct BLEIncomingFileStore {
            }

            let currentUsage = allFiles.reduce(0) { $0 + $1.size }
-            let targetUsage = Self.quotaBytes - Int64(reservingBytes)
+            let targetUsage = quotaBytes - Int64(reservingBytes)
            guard currentUsage > targetUsage else { return }

            let needToFree = currentUsage - targetUsage
+            let activeDeletionPaths = payloadCoordination
+                .deletionReservations.values.reduce(into: Set<String>()) {
+                    $0.formUnion($1)
+                }
+            let protectedPaths = activeDeletionPaths.union(
+                payloadCoordination.pendingDeliveryPaths
+            )
            var freedSpace: Int64 = 0
            for file in allFiles.sorted(by: { $0.modified < $1.modified }) {
                guard freedSpace < needToFree else { break }
+                guard !file.url.lastPathComponent.hasPrefix(Self.liveCapturePrefix) else { continue }
+                guard !protectedPaths.contains(
+                    file.url.standardizedFileURL.path
+                ) else {
+                    continue
+                }
                do {
                    try fileManager.removeItem(at: file.url)
                    freedSpace += file.size
@@ -90,15 +482,46 @@ struct BLEIncomingFileStore {
    }

    private func filesDirectory() throws -> URL {
-        let root = try baseDirectory ?? fileManager.url(
+        let filesDir = try rootDirectory().appendingPathComponent("files", isDirectory: true)
+        try fileManager.createDirectory(at: filesDir, withIntermediateDirectories: true, attributes: nil)
+        return filesDir
+    }
+
+    private func rootDirectory() throws -> URL {
+        try baseDirectory ?? fileManager.url(
            for: .applicationSupportDirectory,
            in: .userDomainMask,
            appropriateFor: nil,
            create: true
        )
-        let filesDir = root.appendingPathComponent("files", isDirectory: true)
-        try fileManager.createDirectory(at: filesDir, withIntermediateDirectories: true, attributes: nil)
-        return filesDir
+    }
+
+    private func panicRecoveryPendingMarkerURL() throws -> URL {
+        try rootDirectory().appendingPathComponent(
+            Self.panicRecoveryPendingMarkerFileName,
+            isDirectory: false
+        )
+    }
+
+    private func panicRecoveryMarkerURLs() throws -> [URL] {
+        let root = try rootDirectory()
+        return [
+            root.appendingPathComponent(
+                Self.panicRecoveryPendingMarkerFileName,
+                isDirectory: false
+            ),
+            root.appendingPathComponent(
+                Self.legacyPanicRecoveryPendingMarkerFileName,
+                isDirectory: false
+            )
+        ]
+    }
+
+    private func isURLInsideFilesDirectory(_ url: URL) -> Bool {
+        guard let filesDirectory = try? filesDirectory().standardizedFileURL else {
+            return false
+        }
+        return url.standardizedFileURL.path.hasPrefix(filesDirectory.path + "/")
    }

    private func sanitizedFileName(_ name: String?, defaultName: String, fallbackExtension: String?) -> String {
@@ -128,11 +551,20 @@ struct BLEIncomingFileStore {
        return candidate.isEmpty ? defaultName : candidate
    }

-    private func uniqueFileURL(in directory: URL, fileName: String) -> URL {
+    private func uniqueFileURL(
+        in directory: URL,
+        fileName: String,
+        reservedPaths: Set<String>,
+        forceRandomizedName: Bool
+    ) -> URL {
        let directoryPath = directory.standardizedFileURL.path
        func isInsideDirectory(_ url: URL) -> Bool {
            url.standardizedFileURL.path.hasPrefix(directoryPath + "/")
        }
+        func isAvailable(_ url: URL) -> Bool {
+            !reservedPaths.contains(url.standardizedFileURL.path)
+                && !fileManager.fileExists(atPath: url.path)
+        }

        var candidate = directory.appendingPathComponent(fileName)
        guard isInsideDirectory(candidate) else {
@@ -140,19 +572,27 @@ struct BLEIncomingFileStore {
            return directory.appendingPathComponent("blocked_\(UUID().uuidString)")
        }

-        if !fileManager.fileExists(atPath: candidate.path) {
+        let baseName = (fileName as NSString).deletingPathExtension
+        let ext = (fileName as NSString).pathExtension
+        if forceRandomizedName {
+            let suffix = UUID().uuidString
+            let randomizedName = ext.isEmpty
+                ? "\(baseName)_\(suffix)"
+                : "\(baseName)_\(suffix).\(ext)"
+            return directory.appendingPathComponent(randomizedName)
+        }
+
+        if isAvailable(candidate) {
            return candidate
        }

-        let baseName = (fileName as NSString).deletingPathExtension
-        let ext = (fileName as NSString).pathExtension
        for counter in 1..<100 {
            let newName = ext.isEmpty ? "\(baseName) (\(counter))" : "\(baseName) (\(counter)).\(ext)"
            candidate = directory.appendingPathComponent(newName)
            guard isInsideDirectory(candidate) else {
                return directory.appendingPathComponent("blocked_\(UUID().uuidString)")
            }
-            if !fileManager.fileExists(atPath: candidate.path) {
+            if isAvailable(candidate) {
                return candidate
            }
        }
@@ -78,11 +78,22 @@ struct BLEIngressLinkRegistry {
            return .failure(.selfLoopback(packetType: packet.type))
        }

-        if let boundPeerID,
-           boundPeerID != claimedSenderID,
-           requiresDirectSenderBinding(packet, directAnnounceTTL: directAnnounceTTL) {
+        if let boundPeerID, boundPeerID != claimedSenderID {
+            if requiresDirectSenderBinding(packet) {
                return .failure(.directSenderMismatch(boundPeerID: boundPeerID, claimedSenderID: claimedSenderID))
            }
+            // A direct announce claiming a new sender on a bound link is either
+            // a spoof or a legitimate peer-ID rotation on a connection that
+            // outlived the old ID. Attribute it to the claimed sender and let
+            // it through: announces are self-authenticating, and only a
+            // signature-verified announce may rebind the link (BLEService).
+            if isDirectAnnounce(packet, directAnnounceTTL: directAnnounceTTL) {
+                return .success(BLEIngressPacketContext(
+                    receivedFromPeerID: claimedSenderID,
+                    validationPeerID: claimedSenderID
+                ))
+            }
+        }

        let receivedFromPeerID = boundPeerID ?? claimedSenderID
        let validationPeerID = packet.isRSR ? receivedFromPeerID : claimedSenderID
@@ -98,12 +109,15 @@ struct BLEIngressLinkRegistry {
        return "\(senderID)-\(packet.timestamp)-\(packet.type)-\(digestPrefix)"
    }

-    private static func requiresDirectSenderBinding(_ packet: BitchatPacket, directAnnounceTTL: UInt8) -> Bool {
+    private static func requiresDirectSenderBinding(_ packet: BitchatPacket) -> Bool {
        // REQUEST_SYNC is never relayed, so on a bound link the claimed sender
        // must be the link peer — it elicits a full store replay, and the
        // response is addressed to whoever the sender claims to be.
-        if packet.type == MessageType.requestSync.rawValue { return true }
-        return packet.type == MessageType.announce.rawValue && packet.ttl == directAnnounceTTL
+        packet.type == MessageType.requestSync.rawValue
+    }
+
+    static func isDirectAnnounce(_ packet: BitchatPacket, directAnnounceTTL: UInt8) -> Bool {
+        packet.type == MessageType.announce.rawValue && packet.ttl == directAnnounceTTL
    }

    private static func isSelfAuthoredSyncResponse(_ packet: BitchatPacket) -> Bool {
@@ -164,7 +164,11 @@ final class BLELinkStateStore {
        guard let peerID else { return [] }

        var links: Set<BLEIngressLinkID> = []
-        if let peripheralUUID = peerToPeripheralUUID[peerID] {
+        // Scan all states rather than the 1:1 reverse map: after a state
+        // restoration the same device can hold several live peripheral links
+        // bound to one peer (it reappears under a fresh UUID while the
+        // restored connection lives on).
+        for (peripheralUUID, state) in peripherals where state.peerID == peerID {
            links.insert(.peripheral(peripheralUUID))
        }
        for (centralUUID, mappedPeerID) in centralToPeerID where mappedPeerID == peerID {
@@ -173,6 +177,13 @@ final class BLELinkStateStore {
        return links
    }

+    /// The peer's most recently bound peripheral link, per peer. Used to keep
+    /// duplicate-link fanout collapse deterministic (see BLEFanoutSelector).
+    var preferredPeripheralBindings: [PeerID: String] {
+        assertOwned()
+        return peerToPeripheralUUID
+    }
+
    func peerID(forPeripheralID peripheralID: String) -> PeerID? {
        assertOwned()
        return peripherals[peripheralID]?.peerID
@@ -203,17 +214,38 @@ final class BLELinkStateStore {

    func bindPeripheral(_ peripheralUUID: String, to peerID: PeerID) {
        assertOwned()
-        if updatePeripheral(peripheralUUID, { $0.peerID = peerID }) != nil {
-            peerToPeripheralUUID[peerID] = peripheralUUID
+        var previousPeerID: PeerID?
+        let updated = updatePeripheral(peripheralUUID) {
+            previousPeerID = $0.peerID
+            $0.peerID = peerID
        }
+        guard updated != nil else { return }
+        // Rebinding (peer-ID rotation): drop the retired ID's reverse mapping
+        // so the old peer no longer claims this link.
+        if let previousPeerID, previousPeerID != peerID,
+           peerToPeripheralUUID[previousPeerID] == peripheralUUID {
+            peerToPeripheralUUID.removeValue(forKey: previousPeerID)
+        }
+        peerToPeripheralUUID[peerID] = peripheralUUID
    }

    func removePeripheral(_ peripheralID: String) -> PeerID? {
        assertOwned()
        let peerID = peripherals.removeValue(forKey: peripheralID)?.peerID
-        if let peerID {
+        // Only clear (or repair) the reverse map when it points at the removed
+        // link: with duplicate links to one peer, removing a stale duplicate
+        // must not strand the peer's surviving bound link.
+        if let peerID, peerToPeripheralUUID[peerID] == peripheralID {
+            // Prefer a writable survivor: repairing onto a link that is
+            // mid-service-rediscovery would strand directed sends until the
+            // characteristic comes back.
+            let survivors = peripherals.filter { $0.value.peerID == peerID && $0.value.isConnected }
+            if let survivorUUID = survivors.first(where: { $0.value.characteristic != nil })?.key ?? survivors.first?.key {
+                peerToPeripheralUUID[peerID] = survivorUUID
+            } else {
                peerToPeripheralUUID.removeValue(forKey: peerID)
            }
+        }
        return peerID
    }

@@ -25,9 +25,4 @@ final class BLELogRateLimiter {
        }
    }

-    func removeAll() {
-        queue.sync {
-            lastLogTimeByKey.removeAll()
-        }
-    }
 }
@@ -1,7 +1,18 @@
 import BitFoundation
 import BitLogger
+import CryptoKit
 import Foundation

+struct BLENoiseHandshakeHandlingResult {
+    let processed: Bool
+    let didEstablishAuthenticatedSession: Bool
+}
+
+struct BLENoiseDecryptionResult {
+    let plaintext: Data
+    let sessionGeneration: UUID
+}
+
 /// Narrow environment for `BLENoisePacketHandler`.
 ///
 /// All queue hops (collections barrier writes, main-actor UI notification)
@@ -16,10 +27,15 @@ struct BLENoisePacketHandlerEnvironment {
    let messageTTL: UInt8
    /// Current time source.
    let now: () -> Date
-    /// Processes an inbound handshake message, returning an optional response payload (crypto).
-    let processHandshakeMessage: (_ peerID: PeerID, _ message: Data) throws -> Data?
+    /// Processes an inbound handshake message, returning its optional response
+    /// and whether that exact candidate authenticated (crypto).
+    let processHandshakeMessage:
+        (_ peerID: PeerID, _ message: Data) throws
+            -> NoiseHandshakeProcessingResult
    /// Whether any Noise session (established or pending) exists for the peer (crypto).
    let hasNoiseSession: (PeerID) -> Bool
+    /// Whether an inbound ordinary XX responder is waiting for message 3.
+    let isAwaitingResponderHandshakeCompletion: (PeerID) -> Bool
    /// Initiates a fresh Noise handshake with the peer (crypto + send).
    let initiateHandshake: (PeerID) -> Void
    /// Broadcasts a packet on the mesh (caller is already on the message queue).
@@ -27,9 +43,16 @@ struct BLENoisePacketHandlerEnvironment {
    /// Updates the registry last-seen timestamp for the peer (async barrier write).
    let updatePeerLastSeen: (PeerID) -> Void
    /// Decrypts an encrypted payload from the peer (crypto).
-    let decrypt: (_ payload: Data, _ peerID: PeerID) throws -> Data
+    let decrypt: (_ payload: Data, _ peerID: PeerID) throws -> BLENoiseDecryptionResult
    /// Clears the peer's Noise session after an unrecoverable decrypt failure (crypto).
    let clearSession: (PeerID) -> Void
+    /// Consumes session-authenticated protocol state inside the transport. It
+    /// must never escape to UI or Nostr payload dispatch.
+    let handleAuthenticatedPeerState: (
+        _ peerID: PeerID,
+        _ payload: Data,
+        _ sessionGeneration: UUID
+    ) -> Void
    /// Delivers `.noisePayloadReceived` to the UI as one main-actor hop.
    let deliverNoisePayload: (
        _ peerID: PeerID,
@@ -43,19 +66,55 @@ struct BLENoisePacketHandlerEnvironment {
 /// processing (with response), encrypted payload decryption and dispatch,
 /// and session recovery on decrypt failure.
 final class BLENoisePacketHandler {
+    private struct DeferredCiphertext {
+        let packet: BitchatPacket
+        let receivedAt: Date
+    }
+
+    /// Early post-handshake packets are normally tiny control messages or
+    /// queued DMs. Keep the recovery surface deliberately small so an
+    /// unauthenticated half-handshake cannot create an unbounded memory queue.
+    private static let maxDeferredPacketsPerPeer = 4
+    private static let maxDeferredPacketsGlobal = 32
+    /// One legacy sender can immediately follow message 3 with the largest
+    /// valid private-file ciphertext and has no application-level retry. Keep
+    /// room for that packet plus a small control-message budget.
+    private static let maxDeferredBytes =
+        NoiseSecurityConstants.maxPrivateFileCiphertextSize + 256 * 1024
+    private static let deferredLifetime =
+        NoiseSecurityConstants.ordinaryResponderHandshakeTimeout
+
    private let environment: BLENoisePacketHandlerEnvironment
+    private let deferredLock = NSLock()
+    private var deferredCiphertexts: [PeerID: [DeferredCiphertext]] = [:]
+    private var deferredCiphertextBytes = 0

    init(environment: BLENoisePacketHandlerEnvironment) {
        self.environment = environment
    }

-    func handleHandshake(_ packet: BitchatPacket, from peerID: PeerID) {
+    /// Returns true when the handshake message was processed successfully.
+    /// Callers use this to distinguish an authenticated reconnect completion
+    /// from a rejected ordinary responder while rollback state is restored.
+    @discardableResult
+    func handleHandshake(_ packet: BitchatPacket, from peerID: PeerID) -> Bool {
+        handleHandshakeWithResult(packet, from: peerID).processed
+    }
+
+    func handleHandshakeWithResult(
+        _ packet: BitchatPacket,
+        from peerID: PeerID
+    ) -> BLENoiseHandshakeHandlingResult {
        let env = environment
        // Use NoiseEncryptionService for handshake processing
        if PeerID(hexData: packet.recipientID) == env.localPeerID() {
            // Handshake is for us
            do {
-                if let response = try env.processHandshakeMessage(peerID, packet.payload) {
+                let result = try env.processHandshakeMessage(
+                    peerID,
+                    packet.payload
+                )
+                if let response = result.response {
                    // Send response
                    let responsePacket = BitchatPacket(
                        type: MessageType.noiseHandshake.rawValue,
@@ -70,19 +129,76 @@ final class BLENoisePacketHandler {
                    env.broadcastPacket(responsePacket)
                }

-                // Session establishment will trigger onPeerAuthenticated callback
-                // which will send any pending messages at the right time
+                // The serialized authentication callback installs transport
+                // state before it drains any bounded early ciphertext.
+                return BLENoiseHandshakeHandlingResult(
+                    processed: true,
+                    didEstablishAuthenticatedSession:
+                        result.didEstablishAuthenticatedSession
+                )
+            } catch let managedFailure as NoiseManagedHandshakeFailure {
+                SecureLogger.error(
+                    "Failed to process handshake; manager owns recovery: \(managedFailure.underlying)"
+                )
+                return BLENoiseHandshakeHandlingResult(
+                    processed: false,
+                    didEstablishAuthenticatedSession: false
+                )
+            } catch NoiseSessionError.peerIdentityMismatch {
+                // The responder was already discarded by the session manager.
+                // Do not let a spoofed claimed ID trigger a fresh outbound
+                // handshake or recreate state for the attacker-selected ID.
+                SecureLogger.warning(
+                    "Rejected Noise handshake whose static key does not match \(peerID.id.prefix(8))…",
+                    category: .security
+                )
+                return BLENoiseHandshakeHandlingResult(
+                    processed: false,
+                    didEstablishAuthenticatedSession: false
+                )
            } catch {
                SecureLogger.error("Failed to process handshake: \(error)")
                // Try initiating a new handshake
                if !env.hasNoiseSession(peerID) {
                    env.initiateHandshake(peerID)
                }
+                return BLENoiseHandshakeHandlingResult(
+                    processed: false,
+                    didEstablishAuthenticatedSession: false
+                )
            }
        }
+        return BLENoiseHandshakeHandlingResult(
+            processed: false,
+            didEstablishAuthenticatedSession: false
+        )
    }

    func handleEncrypted(_ packet: BitchatPacket, from peerID: PeerID) {
+        handleEncrypted(packet, from: peerID, isDeferredRetry: false)
+    }
+
+    /// Called by the transport's serialized authentication callback after it
+    /// has installed state for the promoted or restored session generation.
+    func handleSessionAuthenticated(_ peerID: PeerID) {
+        drainDeferredCiphertextsIfReady(for: peerID)
+    }
+
+    /// Synchronously discards ciphertext retained for a pre-panic Noise
+    /// generation. The handler survives the service's identity replacement,
+    /// so keeping this queue would replay old bytes after post-panic auth.
+    func resetForPanic() {
+        deferredLock.lock()
+        deferredCiphertexts.removeAll(keepingCapacity: false)
+        deferredCiphertextBytes = 0
+        deferredLock.unlock()
+    }
+
+    private func handleEncrypted(
+        _ packet: BitchatPacket,
+        from peerID: PeerID,
+        isDeferredRetry: Bool
+    ) {
        let env = environment
        guard let recipientID = PeerID(hexData: packet.recipientID) else {
            SecureLogger.warning("⚠️ Encrypted message has no recipient ID", category: .session)
@@ -98,35 +214,231 @@ final class BLENoisePacketHandler {
        env.updatePeerLastSeen(peerID)

        do {
-            let decrypted = try env.decrypt(packet.payload, peerID)
+            let decryption = try env.decrypt(packet.payload, peerID)
+            let decrypted = decryption.plaintext
            guard decrypted.count > 0 else { return }

            // First byte indicates the payload type
            let payloadType = decrypted[0]
            let payloadData = decrypted.dropFirst()

-            guard let noisePayloadType = NoisePayloadType(rawValue: payloadType) else {
+            guard let noisePayloadType = NoisePayloadType.decoded(rawValue: payloadType) else {
                SecureLogger.warning("⚠️ Unknown noise payload type: \(payloadType)")
                return
            }

            SecureLogger.debug("🔐 Decrypted noise payload type \(noisePayloadType.description) from \(peerID.id.prefix(8))…", category: .session)

+            if noisePayloadType == .authenticatedPeerState {
+                env.handleAuthenticatedPeerState(
+                    peerID,
+                    Data(payloadData),
+                    decryption.sessionGeneration
+                )
+                return
+            }
+
            let ts = Date(timeIntervalSince1970: Double(packet.timestamp) / 1000)
            env.deliverNoisePayload(peerID, noisePayloadType, Data(payloadData), ts)
+        } catch NoiseEncryptionError.transportGenerationNotReady {
+            if isDeferredRetry {
+                SecureLogger.warning(
+                    "Dropping deferred Noise ciphertext from \(peerID.id.prefix(8))… because its authenticated transport generation changed again",
+                    category: .session
+                )
+                return
+            }
+            // The manager promoted or restored keys before BLE's serialized
+            // callback installed generation-bound transport state. The
+            // manager rejected this before decrypting, so replay is safe.
+            deferCiphertext(packet, from: peerID)
        } catch NoiseEncryptionError.sessionNotEstablished {
+            if isDeferredRetry {
+                SecureLogger.warning(
+                    "Dropping deferred Noise ciphertext from \(peerID.id.prefix(8))… because the authenticated session is unavailable",
+                    category: .session
+                )
+                return
+            }
            // We received an encrypted message before establishing a session with this peer.
-            // Trigger a handshake so future messages can be decrypted.
+            // An initiator may already have sent message 3 followed by this
+            // ciphertext, with BLE delivering the ciphertext first.
+            if env.isAwaitingResponderHandshakeCompletion(peerID) {
+                deferCiphertext(packet, from: peerID)
+                return
+            }
+            // Otherwise trigger a handshake so future messages can decrypt.
            SecureLogger.debug("🔑 Encrypted message from \(peerID.id.prefix(8))… without session; initiating handshake")
            if !env.hasNoiseSession(peerID) {
                env.initiateHandshake(peerID)
            }
        } catch {
+            if isDeferredRetry {
+                // An early packet cannot tear down the authenticated session
+                // merely because its single bounded retry still fails.
+                SecureLogger.warning(
+                    "Dropping deferred Noise ciphertext from \(peerID.id.prefix(8))… after retry failed: \(error)",
+                    category: .session
+                )
+                return
+            }
+            // A responder may retain an older transport as receive-only
+            // rollback state while ordinary XX waits for message 3. New-key
+            // ciphertext can fail against those retained receive keys first.
+            if env.isAwaitingResponderHandshakeCompletion(peerID) {
+                if isDeferrableEarlyHandshakeFailure(error) {
+                    deferCiphertext(packet, from: peerID)
+                } else {
+                    SecureLogger.warning(
+                        "Dropping invalid Noise ciphertext from \(peerID.id.prefix(8))… while responder handshake is completing: \(error)",
+                        category: .session
+                    )
+                }
+                return
+            }
+            if isDropOnlyCiphertextFailure(error) {
+                // The packet is attacker-controlled and did not prove a
+                // transport-state failure. Never let malformed, replayed,
+                // forged, oversized, or rate-limited bytes evict working keys.
+                SecureLogger.warning(
+                    "Dropping rejected Noise ciphertext from \(peerID.id.prefix(8))… without clearing its session: \(error)",
+                    category: .security
+                )
+                return
+            }
            // Decryption failed - clear the corrupted session and re-initiate handshake
-            // This handles cases where session state got out of sync (nonce mismatch, etc.)
+            // Only local/session lifecycle failures reach this path.
            SecureLogger.error("❌ Failed to decrypt message from \(peerID.id.prefix(8))…: \(error) - clearing session and re-initiating handshake")
            env.clearSession(peerID)
            env.initiateHandshake(peerID)
        }
    }
+
+    private func isDeferrableEarlyHandshakeFailure(_ error: Error) -> Bool {
+        if let noiseError = error as? NoiseError {
+            switch noiseError {
+            case .authenticationFailure, .replayDetected:
+                return true
+            default:
+                return false
+            }
+        }
+        if let cryptoError = error as? CryptoKitError,
+           case .authenticationFailure = cryptoError {
+            return true
+        }
+        return false
+    }
+
+    private func isDropOnlyCiphertextFailure(_ error: Error) -> Bool {
+        if let securityError = error as? NoiseSecurityError {
+            switch securityError {
+            case .messageTooLarge, .rateLimitExceeded, .invalidPeerID:
+                return true
+            case .sessionExpired, .sessionExhausted:
+                return false
+            }
+        }
+        if let noiseError = error as? NoiseError {
+            switch noiseError {
+            case .invalidCiphertext, .authenticationFailure, .replayDetected:
+                return true
+            case .uninitializedCipher, .handshakeComplete,
+                    .handshakeNotComplete, .missingLocalStaticKey,
+                    .missingKeys, .invalidMessage, .invalidPublicKey,
+                    .nonceExceeded:
+                return false
+            }
+        }
+        return error is CryptoKitError
+    }
+
+    private func deferCiphertext(_ packet: BitchatPacket, from peerID: PeerID) {
+        guard NoiseSecurityValidator.validatePrivateFileCiphertextSize(
+            packet.payload
+        ) else {
+            SecureLogger.warning(
+                "Dropping oversized early Noise ciphertext from \(peerID.id.prefix(8))…",
+                category: .security
+            )
+            return
+        }
+
+        let now = environment.now()
+        deferredLock.lock()
+        defer { deferredLock.unlock() }
+        purgeExpiredCiphertextsLocked(now: now)
+
+        let peerCount = deferredCiphertexts[peerID]?.count ?? 0
+        let globalCount = deferredCiphertexts.values.reduce(0) {
+            $0 + $1.count
+        }
+        guard peerCount < Self.maxDeferredPacketsPerPeer,
+              globalCount < Self.maxDeferredPacketsGlobal,
+              deferredCiphertextBytes + packet.payload.count
+                <= Self.maxDeferredBytes else {
+            SecureLogger.warning(
+                "Dropping early Noise ciphertext from \(peerID.id.prefix(8))… because the handshake buffer is full",
+                category: .security
+            )
+            return
+        }
+
+        deferredCiphertexts[peerID, default: []].append(
+            DeferredCiphertext(packet: packet, receivedAt: now)
+        )
+        deferredCiphertextBytes += packet.payload.count
+        SecureLogger.debug(
+            "Deferring early Noise ciphertext from \(peerID.id.prefix(8))… until responder handshake completion",
+            category: .session
+        )
+    }
+
+    private func drainDeferredCiphertextsIfReady(for peerID: PeerID) {
+        let env = environment
+        guard !env.isAwaitingResponderHandshakeCompletion(peerID),
+              env.hasNoiseSession(peerID) else {
+            return
+        }
+
+        let now = env.now()
+        deferredLock.lock()
+        purgeExpiredCiphertextsLocked(now: now)
+        let deferred = deferredCiphertexts.removeValue(forKey: peerID) ?? []
+        deferredCiphertextBytes -= deferred.reduce(0) {
+            $0 + $1.packet.payload.count
+        }
+        deferredLock.unlock()
+
+        guard !deferred.isEmpty else { return }
+        SecureLogger.debug(
+            "Retrying \(deferred.count) early Noise ciphertext packet(s) from \(peerID.id.prefix(8))… after handshake completion",
+            category: .session
+        )
+        for item in deferred {
+            handleEncrypted(item.packet, from: peerID, isDeferredRetry: true)
+        }
+    }
+
+    private func purgeExpiredCiphertextsLocked(now: Date) {
+        for peerID in Array(deferredCiphertexts.keys) {
+            guard let items = deferredCiphertexts[peerID] else { continue }
+            let retained = items.filter {
+                now.timeIntervalSince($0.receivedAt) <= Self.deferredLifetime
+            }
+            guard retained.count != items.count else { continue }
+
+            deferredCiphertextBytes -= items.reduce(0) {
+                $0 + $1.packet.payload.count
+            }
+            deferredCiphertextBytes += retained.reduce(0) {
+                $0 + $1.packet.payload.count
+            }
+            if retained.isEmpty {
+                deferredCiphertexts.removeValue(forKey: peerID)
+            } else {
+                deferredCiphertexts[peerID] = retained
+            }
+        }
+    }
 }
@@ -17,6 +17,16 @@ enum BLENoisePayloadFactory {
        typedPayload(.delivered, payload: Data(messageID.utf8))
    }

+    static func privateFile(_ filePacket: BitchatFilePacket) -> Data? {
+        guard let payload = filePacket.encode() else { return nil }
+        return typedPayload(.privateFile, payload: payload)
+    }
+
+    static func authenticatedPeerState(_ state: AuthenticatedPeerStatePacket) -> Data? {
+        guard let payload = state.encode() else { return nil }
+        return typedPayload(.authenticatedPeerState, payload: payload)
+    }
+
    static func typedPayload(_ type: NoisePayloadType, payload: Data) -> Data {
        var typed = Data([type.rawValue])
        typed.append(payload)
@@ -0,0 +1,40 @@
+import Foundation
+
+/// Bounds ordinary Noise revalidation to one attempt per physical-link epoch.
+/// A live epoch may retry after the cooldown so a lost handshake cannot leave
+/// the link permanently unauthenticated.
+struct BLENoiseReconnectPolicy {
+    static let minimumRetryInterval: TimeInterval = 60
+
+    private var lastAttemptAt: [BLEIngressLinkID: Date] = [:]
+
+    mutating func shouldRevalidate(
+        on link: BLEIngressLinkID,
+        hasEstablishedSession: Bool,
+        isNoiseAuthenticatedLink: Bool,
+        hasAuthenticatedPeerLink: Bool,
+        now: Date
+    ) -> Bool {
+        guard hasEstablishedSession,
+              !isNoiseAuthenticatedLink,
+              !hasAuthenticatedPeerLink else {
+            return false
+        }
+        if let previous = lastAttemptAt[link],
+           now.timeIntervalSince(previous) < Self.minimumRetryInterval {
+            return false
+        }
+        lastAttemptAt[link] = now
+        return true
+    }
+
+    /// Link identifiers can be stable across CoreBluetooth reconnects, so a
+    /// disconnect explicitly starts a new epoch and permits one fresh attempt.
+    mutating func endLinkEpoch(_ link: BLEIngressLinkID) {
+        lastAttemptAt.removeValue(forKey: link)
+    }
+
+    mutating func removeAll() {
+        lastAttemptAt.removeAll()
+    }
+}
@@ -6,9 +6,16 @@ struct BLEPendingPrivateMessage: Equatable {
    let messageID: String
 }

+struct BLEPendingTypedPayload: Equatable {
+    let payload: Data
+    /// Present for app-initiated media so handshake queuing preserves the
+    /// fragment scheduler's progress/cancellation identity.
+    let transferId: String?
+}
+
 struct BLENoiseSessionQueues {
    private var privateMessagesByPeerID: [PeerID: [BLEPendingPrivateMessage]] = [:]
-    private var typedPayloadsByPeerID: [PeerID: [Data]] = [:]
+    private var typedPayloadsByPeerID: [PeerID: [BLEPendingTypedPayload]] = [:]

    var isEmpty: Bool {
        privateMessagesByPeerID.isEmpty && typedPayloadsByPeerID.isEmpty
@@ -34,13 +41,35 @@ struct BLENoiseSessionQueues {
        privateMessagesByPeerID[peerID, default: []].insert(contentsOf: messages, at: 0)
    }

-    mutating func appendTypedPayload(_ payload: Data, for peerID: PeerID) {
-        typedPayloadsByPeerID[peerID, default: []].append(payload)
+    mutating func appendTypedPayload(_ payload: Data, transferId: String? = nil, for peerID: PeerID) {
+        typedPayloadsByPeerID[peerID, default: []].append(
+            BLEPendingTypedPayload(payload: payload, transferId: transferId)
+        )
    }

-    mutating func takeTypedPayloads(for peerID: PeerID) -> [Data] {
+    mutating func takeTypedPayloads(for peerID: PeerID) -> [BLEPendingTypedPayload] {
        let payloads = typedPayloadsByPeerID[peerID] ?? []
        typedPayloadsByPeerID.removeValue(forKey: peerID)
        return payloads
    }
+
+    func containsTypedPayload(transferId: String) -> Bool {
+        typedPayloadsByPeerID.values.contains { payloads in
+            payloads.contains { $0.transferId == transferId }
+        }
+    }
+
+    @discardableResult
+    mutating func removeTypedPayload(transferId: String) -> Bool {
+        for peerID in Array(typedPayloadsByPeerID.keys) {
+            guard var payloads = typedPayloadsByPeerID[peerID],
+                  let index = payloads.firstIndex(where: { $0.transferId == transferId }) else {
+                continue
+            }
+            payloads.remove(at: index)
+            typedPayloadsByPeerID[peerID] = payloads.isEmpty ? nil : payloads
+            return true
+        }
+        return false
+    }
 }
--- a/Show More
+++ b/Show More
				`@@ -0,0 +1 @@`
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