diff --git a/lib/backend/modules/file_uploader.dart b/lib/backend/modules/file_uploader.dart
index 5d5be94..3967ebe 100644
--- a/lib/backend/modules/file_uploader.dart
+++ b/lib/backend/modules/file_uploader.dart
@@ -101,6 +101,7 @@ class FileUploader {
                   url: info.url,
                   path: file.path,
                   filename: filename,
+                  connection: 'close',
                 )
                 .listen(
                   (e) {
@@ -185,6 +186,8 @@ class FileUploader {
           url: uri.toString(),
           path: file.path,
           filename: _syntheticFilename(),
+          contentType: 'application/octet-stream',
+          connection: 'close',
         ),
         onProgress: onProgress,
       );
@@ -277,6 +280,11 @@ class FileUploader {
         ),
         onProgress: onProgress,
       );
+      if (result.error != null || result.status != 200) {
+        logger.w(
+          'uploadVideoFile: status=${result.status} error=${result.error}',
+        );
+      }
       return result.error == null && result.status == 200;
     } catch (e) {
       logger.w('uploadVideoFile: $e');
diff --git a/lib/core/calls/conversation_params.dart b/lib/core/calls/conversation_params.dart
index 64a9e2a..8000c77 100644
--- a/lib/core/calls/conversation_params.dart
+++ b/lib/core/calls/conversation_params.dart
@@ -1,7 +1,4 @@
-import 'dart:convert';
-import 'dart:typed_data';
-
-import '../protocol/lz4_block.dart';
+import 'package:kolibri/kolibri.dart' as kb;
 
 /// Параметры подключения к звонку (`vcp`), которые сервер присылает в пуше
 /// входящего звонка (opcode 137) и в ответе на инициацию исходящего.
@@ -79,73 +76,19 @@ class ConversationParams {
     return nowSec >= expiresAt! - 5;
   }
 
-  static List<String> _splitTurn(Object? value) {
-    if (value is! String || value.isEmpty) return const [];
-    return value
-        .split(',')
-        .map((e) => e.trim())
-        .where((e) => e.isNotEmpty)
-        .toList();
-  }
-
-  static List<String> _stringList(Object? value) {
-    if (value is! List) return const [];
-    return value.whereType<String>().toList();
-  }
-
-  /// Распаковывает и парсит строку `vcp`. Возвращает `null`, если формат
-  /// не распознан.
+  /// Распаковывает и парсит строку `vcp` через Rust-ядро (kolibri). Возвращает
+  /// `null`, если формат не распознан. Требует инициализации `initKolibri()`.
   static ConversationParams? decode(String vcp) {
-    final sep = vcp.indexOf(':');
-    if (sep <= 0) return null;
-
-    final rawLen = int.tryParse(vcp.substring(0, sep));
-    if (rawLen == null || rawLen <= 0) return null;
-
-    final Uint8List compressed;
-    try {
-      compressed = base64.decode(vcp.substring(sep + 1));
-    } catch (_) {
-      return null;
-    }
-
-    final Uint8List bytes;
-    try {
-      final decompressed = lz4BlockDecompress(compressed, rawLen);
-      bytes = decompressed.length > rawLen
-          ? Uint8List.sublistView(decompressed, 0, rawLen)
-          : decompressed;
-    } catch (_) {
-      return null;
-    }
-
-    final Object? json;
-    try {
-      json = jsonDecode(utf8.decode(bytes));
-    } catch (_) {
-      return null;
-    }
-    if (json is! Map) return null;
-
-    final token = json['tkn'];
-    final wse = json['wse'];
-    if (token is! String || wse is! String) return null;
-
+    final kb.CallParams? p = kb.decodeVcp(vcp: vcp, conversationId: '');
+    if (p == null) return null;
     return ConversationParams(
-      token: token,
-      wsEndpoint: wse,
-      wsIps: _stringList(json['wsip']),
-      wtEndpoint: json['wte'] as String?,
-      wtIps: _stringList(json['wtip']),
-      callsApiEndpoint: json['vcae'] as String?,
-      callsApiIps: _stringList(json['vcaip']),
-      clientType: json['srcp'] as String?,
-      expiresAt: json['et'] is int ? json['et'] as int : null,
-      stun: json['stne'] as String?,
-      turn: _splitTurn(json['trne']),
-      turnUser: json['trnu'] as String?,
-      turnPassword: json['trnp'] as String?,
-      isVideo: json['iv'] == true,
+      token: p.token,
+      wsEndpoint: p.wsEndpoint,
+      stun: p.stun,
+      turn: p.turn,
+      turnUser: p.turnUser,
+      turnPassword: p.turnPassword,
+      isVideo: p.isVideo,
     );
   }
 }
diff --git a/lib/core/calls/ws2_signaling.dart b/lib/core/calls/ws2_signaling.dart
index 5f0f242..d3d952b 100644
--- a/lib/core/calls/ws2_signaling.dart
+++ b/lib/core/calls/ws2_signaling.dart
@@ -1,8 +1,8 @@
 import 'dart:async';
 import 'dart:convert';
-import 'dart:io';
 
-import '../utils/logger.dart';
+import 'package:kolibri/kolibri.dart' as kb;
+
 import 'conversation_params.dart';
 
 /// Параметры подключения к сигналинг-сокету ws2.
@@ -84,17 +84,19 @@ class Ws2CommandException implements Exception {
 
 /// Клиент сигналинга звонка поверх WebSocket `ws2`.
 ///
-/// Конверт сообщений (подтверждено захватом `docs/ws2_capture.log`):
+/// Тонкий адаптер над Rust-ядром (kolibri [kb.CallSignaling]): ядро держит
+/// WebSocket, корреляцию `sequence`/`response`, keepalive `ping`→`pong` и
+/// разбор кадров; здесь — прежний Dart-интерфейс для [call_session].
+///
+/// Конверт сообщений:
 /// - запрос: `{"command": ..., ..., "sequence": N}`
 /// - ответ:  `{"sequence": N, "response": "<command>", "type": "response"}`
 /// - пуш:    `{..., "notification": "<name>", "type": "notification"}`
-/// - keepalive: текстовый кадр `ping` → ответ `pong`.
 class Ws2Signaling {
   final Ws2Config config;
 
-  WebSocket? _socket;
-  int _sequence = 0;
-  final Map<int, Completer<Map<String, dynamic>>> _pending = {};
+  kb.CallSignaling? _call;
+  StreamSubscription<String>? _notifSub;
 
   final _notifications = StreamController<Map<String, dynamic>>.broadcast();
   final _closed = Completer<Object?>();
@@ -104,106 +106,60 @@ class Ws2Signaling {
   /// Пуши сервера (`type == "notification"`). Фильтруй по полю `notification`.
   Stream<Map<String, dynamic>> get notifications => _notifications.stream;
 
-  /// Завершается, когда сокет закрыт (значение — причина закрытия, если была).
+  /// Завершается, когда сокет закрыт.
   Future<Object?> get done => _closed.future;
 
-  bool get isConnected => _socket != null;
+  bool get isConnected => _call?.isConnected() ?? false;
 
   Future<void> connect() async {
-    final socket = await WebSocket.connect(
-      config.uri.toString(),
-      headers: {'User-Agent': 'okhttp/4.12.0'},
+    final call = await kb.connectCallSignaling(
+      url: config.uri.toString(),
+      userAgent: 'okhttp/4.12.0',
     );
-    _socket = socket;
-    socket.listen(
-      _onFrame,
-      onError: _onDone,
+    _call = call;
+    _notifSub = call.notifications().listen(
+      (json) {
+        Object? decoded;
+        try {
+          decoded = jsonDecode(json);
+        } catch (_) {
+          return;
+        }
+        if (decoded is Map<String, dynamic>) _notifications.add(decoded);
+      },
+      onError: (_) => _onDone(null),
       onDone: () => _onDone(null),
       cancelOnError: false,
     );
   }
 
-  void _onFrame(dynamic frame) {
-    if (frame is String && frame == 'ping') {
-      _socket?.add('pong');
-      return;
-    }
-
-    final String text;
-    if (frame is String) {
-      text = frame;
-    } else if (frame is List<int>) {
-      text = utf8.decode(frame);
-    } else {
-      return;
-    }
-
-    Object? decoded;
-    try {
-      decoded = jsonDecode(text);
-    } catch (_) {
-      return;
-    }
-    if (decoded is! Map<String, dynamic>) return;
-
-    final label =
-        decoded['notification'] ?? decoded['response'] ?? decoded['type'];
-    final dump = jsonEncode(decoded);
-    logger.t('[ws2] ← $label');
-    logger.t(dump.length > 1500
-        ? '${dump.substring(0, 1500)}… (${dump.length}b)'
-        : dump);
-
-    final type = decoded['type'];
-    if (type == 'response' || type == 'error') {
-      final seq = decoded['sequence'];
-      if (seq is int) {
-        final completer = _pending.remove(seq);
-        if (completer != null && !completer.isCompleted) {
-          completer.complete(decoded);
-        }
-      }
-      if (type == 'error') _notifications.add(decoded);
-      return;
-    }
-
-    if (type == 'notification' || decoded.containsKey('notification')) {
-      _notifications.add(decoded);
-    }
-  }
-
   void _onDone(Object? error) {
-    for (final c in _pending.values) {
-      if (!c.isCompleted) c.completeError(error ?? const SocketException('ws2 closed'));
-    }
-    _pending.clear();
     if (!_closed.isCompleted) _closed.complete(error);
     if (!_notifications.isClosed) _notifications.close();
   }
 
   /// Отправляет команду и ждёт ответ сервера. Бросает [Ws2CommandException],
-  /// если в ответе есть поле `error`.
+  /// если сервер вернул ошибку.
   Future<Map<String, dynamic>> sendCommand(
     String command, {
     Map<String, dynamic> extra = const {},
     Duration timeout = const Duration(seconds: 15),
-  }) {
-    final socket = _socket;
-    if (socket == null) {
+  }) async {
+    final call = _call;
+    if (call == null) {
       return Future.error(StateError('ws2 не подключён'));
     }
-
-    final seq = ++_sequence;
-    final completer = Completer<Map<String, dynamic>>();
-    _pending[seq] = completer;
-
-    socket.add(jsonEncode({'command': command, ...extra, 'sequence': seq}));
-
-    return completer.future.timeout(timeout).then((response) {
-      final error = response['error'];
-      if (error != null) throw Ws2CommandException(command, error);
-      return response;
-    });
+    try {
+      final response = await call
+          .sendCommand(command: command, extraJson: jsonEncode(extra))
+          .timeout(timeout);
+      final decoded = jsonDecode(response);
+      return decoded is Map<String, dynamic>
+          ? decoded
+          : <String, dynamic>{};
+    } catch (e) {
+      throw Ws2CommandException(command, e);
+    }
   }
 
   /// Передаёт SDP (offer/answer) другому участнику.
@@ -329,7 +285,9 @@ class Ws2Signaling {
           extra: {'mediaSource': mediaSource, 'layers': layers});
 
   Future<void> close() async {
-    await _socket?.close();
-    _socket = null;
+    await _notifSub?.cancel();
+    _notifSub = null;
+    _call?.close();
+    _call = null;
   }
 }
diff --git a/lib/core/protocol/lz4_block.dart b/lib/core/protocol/lz4_block.dart
deleted file mode 100644
index 55d1529..0000000
--- a/lib/core/protocol/lz4_block.dart
+++ /dev/null
@@ -1,71 +0,0 @@
-import 'dart:typed_data';
-
-/// LZ4 block декомпрессия (без frame-заголовка).
-///
-/// Сервер шлёт block-формат как в транспорте (payload пакетов), так и в
-/// `vcp`-параметрах звонка. dart_lz4 поддерживает только frame-формат, поэтому
-/// block распаковывается вручную.
-Uint8List lz4BlockDecompress(Uint8List src, int maxSize) {
-  var out = Uint8List(1024);
-  int outLen = 0;
-  int pos = 0;
-
-  void ensure(int extra) {
-    if (outLen + extra > maxSize) throw StateError('LZ4: превышен лимит');
-    if (outLen + extra <= out.length) return;
-    var newCap = out.length * 2;
-    while (newCap < outLen + extra) {
-      newCap *= 2;
-    }
-    if (newCap > maxSize) newCap = maxSize;
-    final grown = Uint8List(newCap);
-    grown.setRange(0, outLen, out);
-    out = grown;
-  }
-
-  while (pos < src.length) {
-    final token = src[pos++];
-    var litLen = token >> 4;
-
-    if (litLen == 15) {
-      while (pos < src.length) {
-        final b = src[pos++];
-        litLen += b;
-        if (b != 255) break;
-      }
-    }
-
-    if (litLen > 0) {
-      ensure(litLen);
-      out.setRange(outLen, outLen + litLen, src, pos);
-      outLen += litLen;
-      pos += litLen;
-    }
-
-    if (pos >= src.length) break;
-
-    if (pos + 1 >= src.length) throw StateError('LZ4: unexpected end of input');
-    final offset = src[pos] | (src[pos + 1] << 8);
-    pos += 2;
-    if (offset == 0) throw StateError('LZ4: offset = 0');
-
-    var matchLen = (token & 0x0F) + 4;
-    if ((token & 0x0F) == 0x0F) {
-      while (pos < src.length) {
-        final b = src[pos++];
-        matchLen += b;
-        if (b != 255) break;
-      }
-    }
-
-    ensure(matchLen);
-    final start = outLen - offset;
-    if (start < 0) throw StateError('LZ4: offset за пределами вывода');
-    for (var i = 0; i < matchLen; i++) {
-      out[outLen + i] = out[start + i];
-    }
-    outLen += matchLen;
-  }
-
-  return Uint8List.sublistView(out, 0, outLen);
-}
diff --git a/lib/core/push/push_service.dart b/lib/core/push/push_service.dart
index 4ecb356..3a21860 100644
--- a/lib/core/push/push_service.dart
+++ b/lib/core/push/push_service.dart
@@ -5,6 +5,7 @@ import 'package:firebase_core/firebase_core.dart';
 import 'package:firebase_messaging/firebase_messaging.dart';
 import 'package:flutter/widgets.dart';
 import 'package:flutter_local_notifications/flutter_local_notifications.dart';
+import 'package:kolibri/kolibri.dart' show initKolibri;
 import 'package:shared_preferences/shared_preferences.dart';
 
 import '../../backend/api.dart';
@@ -53,6 +54,9 @@ Future<void> _handleCallDecline(String payloadJson) async {
   }
   if (vcp.isEmpty || conversationId.isEmpty) return;
 
+  // Фоновый изолят: инициализируем ядро перед vcp-декодом/сигналингом.
+  await initKolibri();
+
   final params = ConversationParams.decode(vcp);
   if (params == null) return;
 
@@ -83,6 +87,7 @@ Future<void> _handleReply(String payloadJson, String text) async {
   if (account == 0 || chatId == 0) return;
 
   WidgetsFlutterBinding.ensureInitialized();
+  await initKolibri();
   if (AppInstance.isNamed) {
     try {
       SharedPreferences.setPrefix('flutter.${AppInstance.id}.');
diff --git a/lib/frontend/screens/webapp/web_app_screen.dart b/lib/frontend/screens/webapp/web_app_screen.dart
index 114db51..1acfd16 100644
--- a/lib/frontend/screens/webapp/web_app_screen.dart
+++ b/lib/frontend/screens/webapp/web_app_screen.dart
@@ -6,6 +6,7 @@ import 'package:material_symbols_icons/symbols.dart';
 
 import '../../../backend/modules/webapp.dart';
 import '../../../core/storage/spoofing_service.dart';
+import '../../../main.dart' show api;
 import '../../widgets/connection_status.dart';
 import '../../widgets/error_view.dart';
 import '../../widgets/webview_permission_prompt.dart';
@@ -63,7 +64,11 @@ class _WebAppScreenState extends State<WebAppScreen> {
       _launch = null;
     });
     try {
-      _userAgent = await SpoofingService.getWebViewUserAgent() ?? '';
+      // Тот же UA, что уходит в sessionInit (из handshake-устройства ядра),
+      // чтобы веб-аппы видели нативный клиент; фолбэк — браузерный UA спуфа.
+      _userAgent = api.session?.userAgent() ??
+          await SpoofingService.getWebViewUserAgent() ??
+          '';
       final launch = await widget.loader();
       if (!mounted) return;
       setState(() => _launch = launch);
diff --git a/pubspec.lock b/pubspec.lock
index 71bb253..57a1c9b 100644
--- a/pubspec.lock
+++ b/pubspec.lock
@@ -201,14 +201,6 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.0.2"
-  dart_lz4:
-    dependency: "direct main"
-    description:
-      name: dart_lz4
-      sha256: e2e9c30fdf83a7a1e63bc6c4d90786cf795c38eefee40b1f4c35ea6480c91db9
-      url: "https://pub.dev"
-    source: hosted
-    version: "1.2.0"
   dart_webrtc:
     dependency: transitive
     description:
diff --git a/pubspec.yaml b/pubspec.yaml
index 8146c77..30eb5d0 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -35,13 +35,13 @@ dependencies:
   intl: any
 
   # Rust networking core (kolibri) — FFI plugin, replaces the Dart transport.
-  # Vendored as a git submodule (third_party/kolibri).
+  # DEV: local path for fast iteration; re-pin to third_party/kolibri submodule
+  # (path: third_party/kolibri/kolibri-dart) before merge.
   kolibri:
     path: third_party/kolibri/kolibri-dart
 
   # The following adds the Cupertino Icons font to your application.
   # Use with the CupertinoIcons class for iOS style icons.
-  dart_lz4: ^1.0.0
   crypto: ^3.0.7
   ffi: ^2.1.0
   logger: ^2.6.2
diff --git a/third_party/kolibri b/third_party/kolibri
index 949e70a..8f6836c 160000
--- a/third_party/kolibri
+++ b/third_party/kolibri
@@ -1 +1 @@
-Subproject commit 949e70a1a5e9f38d57360cbc9869d701cec71da9
+Subproject commit 8f6836cac2198027697ed0702044426e84d6f78b