diff --git a/packages/node/meshnet_node/model_backend.py b/packages/node/meshnet_node/model_backend.py
index 00d04f6..ef189fa 100644
--- a/packages/node/meshnet_node/model_backend.py
+++ b/packages/node/meshnet_node/model_backend.py
@@ -134,8 +134,9 @@ class TorchModelShard:
                     self.model.to(self.device)
         except Exception as exc:
             if _looks_like_oom(exc):
+                memory_kind = "VRAM" if self.device.type == "cuda" else "RAM"
                 raise InsufficientVRAMError(
-                    f"insufficient VRAM to load {model_id} layers {shard_start}:{shard_end} "
+                    f"insufficient {memory_kind} to load {model_id} layers {shard_start}:{shard_end} "
                     f"with {quantization} quantization; choose a smaller shard or lower quantization"
                 ) from exc
             raise
@@ -411,7 +412,7 @@ def _should_partial_materialize_shard(
         return False
     if total_layers_hint is None:
         return False
-    return not (shard_start == 0 and shard_end >= total_layers_hint - 1)
+    return True
 
 
 def _load_partial_model_from_snapshot(
@@ -476,7 +477,7 @@ def _load_partial_model_from_snapshot(
         )
 
     with init_empty_weights_fn():
-        model = auto_model_for_causal_lm.from_config(cfg, torch_dtype=dtype)
+        model = auto_model_for_causal_lm.from_config(_causal_lm_config(cfg), torch_dtype=dtype)
     tie_weights = getattr(model, "tie_weights", None)
     if callable(tie_weights):
         tie_weights()
@@ -498,7 +499,7 @@ def _load_partial_model_from_snapshot(
             for tensor_name in names:
                 set_tensor_fn(
                     model,
-                    tensor_name,
+                    _checkpoint_tensor_name_for_model(model, tensor_name),
                     device,
                     value=handle.get_tensor(tensor_name),
                     dtype=dtype,
@@ -569,38 +570,74 @@ def _native_torch_dtype(cfg: Any, torch: Any) -> Any:
     return torch.bfloat16
 
 
+def _causal_lm_config(cfg: Any) -> Any:
+    """Use the text decoder config for composite VLM/MoE presets."""
+    get_text_config = getattr(cfg, "get_text_config", None)
+    if callable(get_text_config):
+        try:
+            return get_text_config()
+        except Exception:
+            pass
+    text_config = getattr(cfg, "text_config", None)
+    if text_config is not None:
+        return text_config
+    return cfg
+
+
+def _checkpoint_tensor_name_for_model(model: Any, tensor_name: str) -> str:
+    """Map multimodal checkpoint keys onto text-only CausalLM modules when needed."""
+    inner = getattr(model, "model", None)
+    if inner is not None and hasattr(inner, "language_model"):
+        return tensor_name
+    if ".language_model." in tensor_name:
+        return tensor_name.replace(".language_model.", ".")
+    return tensor_name
+
+
+def _transformer_backbone(model: Any) -> Any:
+    if hasattr(model, "model"):
+        inner = model.model
+        language_model = getattr(inner, "language_model", None)
+        if language_model is not None:
+            return language_model
+        return inner
+    if hasattr(model, "transformer"):
+        return model.transformer
+    raise ModelBackendError(
+        "unsupported HuggingFace model architecture: no transformer backbone found"
+    )
+
+
 def _model_layers(model: Any) -> Any:
-    if hasattr(model, "model") and hasattr(model.model, "layers"):
-        return model.model.layers
-    if hasattr(model, "transformer") and hasattr(model.transformer, "h"):
-        return model.transformer.h
+    backbone = _transformer_backbone(model)
+    for attr in ("layers", "h", "blocks"):
+        layers = getattr(backbone, attr, None)
+        if layers is not None:
+            return layers
     raise ModelBackendError(
         "unsupported HuggingFace model architecture: no transformer layers found"
     )
 
 
 def _embed_tokens(model: Any) -> Any:
-    if hasattr(model, "model") and hasattr(model.model, "embed_tokens"):
-        return model.model.embed_tokens
-    if hasattr(model, "transformer") and hasattr(model.transformer, "wte"):
-        return model.transformer.wte
+    backbone = _transformer_backbone(model)
+    for attr in ("embed_tokens", "wte"):
+        embed = getattr(backbone, attr, None)
+        if embed is not None:
+            return embed
     raise ModelBackendError(
         "unsupported HuggingFace model architecture: no token embeddings found"
     )
 
 
 def _position_embeddings(model: Any) -> Any | None:
-    if hasattr(model, "transformer") and hasattr(model.transformer, "wpe"):
-        return model.transformer.wpe
-    return None
+    backbone = _transformer_backbone(model)
+    return getattr(backbone, "wpe", None)
 
 
 def _rotary_embedding_module(model: Any) -> Any | None:
-    if hasattr(model, "model") and hasattr(model.model, "rotary_emb"):
-        return model.model.rotary_emb
-    if hasattr(model, "transformer") and hasattr(model.transformer, "rotary_emb"):
-        return model.transformer.rotary_emb
-    return None
+    backbone = _transformer_backbone(model)
+    return getattr(backbone, "rotary_emb", None)
 
 
 def _active_modules_for_shard(model: Any, shard_start: int, shard_end: int) -> list[Any]:
@@ -627,10 +664,11 @@ def _active_modules_for_shard(model: Any, shard_start: int, shard_end: int) -> l
 
 
 def _final_norm(model: Any) -> Any | None:
-    if hasattr(model, "model") and hasattr(model.model, "norm"):
-        return model.model.norm
-    if hasattr(model, "transformer") and hasattr(model.transformer, "ln_f"):
-        return model.transformer.ln_f
+    backbone = _transformer_backbone(model)
+    for attr in ("norm", "ln_f", "final_layer_norm"):
+        norm = getattr(backbone, attr, None)
+        if norm is not None:
+            return norm
     return None
 
 
@@ -743,7 +781,12 @@ def _looks_like_oom(exc: BaseException) -> bool:
     current: BaseException | None = exc
     while current is not None:
         text = str(current).lower()
-        if "out of memory" in text or "cuda error: out of memory" in text:
+        if (
+            "out of memory" in text
+            or "cuda error: out of memory" in text
+            or "paging file is too small" in text
+            or "os error 1455" in text
+        ):
             return True
         current = current.__cause__ or current.__context__
     return False
diff --git a/packages/node/meshnet_node/startup.py b/packages/node/meshnet_node/startup.py
index f5a07ee..54fa139 100644
--- a/packages/node/meshnet_node/startup.py
+++ b/packages/node/meshnet_node/startup.py
@@ -995,6 +995,20 @@ def run_startup(
     )
     if user_pinned_shard:
         shard_label = f"{shard_label} (pinned)"
+    if user_pinned_shard and assigned_total_layers and assignment_bytes_per_layer:
+        pinned_layers = shard_end - shard_start + 1
+        max_layers = _max_assignable_layers(
+            memory_budget_mb,
+            assigned_total_layers,
+            assignment_bytes_per_layer,
+        )
+        if pinned_layers > max_layers:
+            raise ValueError(
+                f"Pinned shard layers {shard_start}–{shard_end} ({pinned_layers} layers) exceed "
+                f"the {memory_budget_mb / 1024:.1f} GB {memory_budget_source} budget "
+                f"(fits up to {max_layers}/{assigned_total_layers} layers at bfloat16). "
+                "Drop --shard-start/--shard-end to let the tracker auto-assign, or pin a smaller range."
+            )
     print(f"  Shard: {shard_label}", flush=True)
 
     # 4. Download shard
@@ -1020,7 +1034,77 @@ def run_startup(
     )
     print(f"  Cached at: {shard_path}", flush=True)
 
-    # 5. Start HTTP server
+    # 5. Start HTTP server — real HF weights use TorchNodeServer; stub-model stays stub.
+    _node_start_time = time.monotonic()
+    if hf_repo and assigned_model != "stub-model":
+        print("Loading real PyTorch model shard...", flush=True)
+        node = TorchNodeServer(
+            host=host,
+            port=port,
+            model_id=hf_repo,
+            shard_start=shard_start,
+            shard_end=shard_end,
+            quantization=quantization,
+            tracker_url=tracker_url,
+            route_timeout=route_timeout,
+            cache_dir=shard_path,
+            debug=debug,
+            max_loaded_shards=max_loaded_shards,
+        )
+        actual_port = node.start()
+        total_layers = getattr(getattr(node, "backend", None), "total_layers", None) or assigned_total_layers
+        shard_label = _format_shard_label(shard_start, shard_end, total_layers, model_name=assigned_model)
+        if user_pinned_shard:
+            shard_label = f"{shard_label} (pinned)"
+        public_host = advertise_host or (socket.getfqdn() if host == "0.0.0.0" else host)
+        endpoint = f"http://{public_host}:{actual_port}"
+        local_base_url = f"http://127.0.0.1:{actual_port}"
+        relay_bridge, relay_fields = _start_relay_bridge_if_available(
+            tracker_url,
+            address,
+            local_base_url,
+            endpoint,
+            relay_url=relay_url,
+        )
+        _attach_relay_bridge(node, relay_bridge)
+        reg_payload = {
+            "endpoint": endpoint,
+            "model": assigned_model,
+            "hf_repo": hf_repo,
+            "num_layers": total_layers,
+            "shard_start": shard_start,
+            "shard_end": shard_end,
+            "downloaded_models": downloaded_models,
+            "hardware_profile": hw,
+            "wallet_address": address,
+            "quantization": quantization,
+            "score": 1.0,
+            "tracker_mode": (shard_start == 0),
+            "managed_assignment": not user_pinned_shard,
+            "model_metadata": model_metadata_for(hf_repo, total_layers, cache_dir=shard_path),
+            **registration_capabilities,
+            **relay_fields,
+        }
+        tracker_node_id = _register_with_tracker(
+            tracker_url, reg_payload, node, _node_start_time,
+        )
+        print(
+            f"\n{'=' * 32}\n"
+            f"meshnet-node ready\n"
+            f"  Wallet:       {address}\n"
+            f"  Model ID:     {hf_repo}\n"
+            f"  Shard:        {shard_label}\n"
+            f"  {_shard_budget_line(memory_budget_mb, memory_budget_source, total_layers, quantization, bytes_per_layer=assignment_bytes_per_layer)}\n"
+            f"  Quantization: {quantization}\n"
+            f"  Endpoint:     {endpoint}\n"
+            f"  Node ID:      {tracker_node_id or 'unregistered'}\n"
+            f"  Hardware:     {_hardware_label(device, gpu_name)}\n"
+            f"  Benchmark:    {bench_tps:,.0f} (throughput index)\n"
+            f"{'=' * 32}",
+            flush=True,
+        )
+        return node
+
     is_last = shard_end >= assignment.get("model_layers_end", shard_end)
     node = StubNodeServer(
         host=host,
@@ -1031,7 +1115,6 @@ def run_startup(
         model=assigned_model,
         shard_path=shard_path,
     )
-    _node_start_time = time.monotonic()
     actual_port = node.start()
     public_host = advertise_host or (socket.getfqdn() if host == "0.0.0.0" else host)
     endpoint = f"http://{public_host}:{actual_port}"
diff --git a/packages/tracker/meshnet_tracker/dashboard.html b/packages/tracker/meshnet_tracker/dashboard.html
index 1c16306..ffda954 100644
--- a/packages/tracker/meshnet_tracker/dashboard.html
+++ b/packages/tracker/meshnet_tracker/dashboard.html
@@ -8,14 +8,20 @@
   :root { --bg:#0d1117; --panel:#161b22; --border:#30363d; --fg:#c9d1d9;
           --dim:#8b949e; --accent:#58a6ff; --ok:#3fb950; --bad:#f85149; --warn:#d29922; }
   * { box-sizing:border-box; }
+  html, body { height:100%; }
   body { margin:0; background:var(--bg); color:var(--fg);
          font:13px/1.5 ui-monospace,SFMono-Regular,Menlo,Consolas,monospace; }
+  body.chat-tab-active { overflow:hidden; height:100dvh; display:flex; flex-direction:column; }
   header { display:flex; align-items:baseline; gap:14px; padding:14px 20px;
-           border-bottom:1px solid var(--border); }
+           border-bottom:1px solid var(--border); flex-shrink:0; }
   header h1 { font-size:16px; margin:0; color:var(--accent); }
   header .meta { color:var(--dim); font-size:12px; }
   main { display:grid; grid-template-columns:repeat(auto-fit,minmax(340px,1fr));
          gap:14px; padding:14px 20px; }
+  body.chat-tab-active main {
+    flex:1; min-height:0; display:flex; flex-direction:column;
+    padding:0; gap:0; overflow:hidden;
+  }
   section { background:var(--panel); border:1px solid var(--border);
             border-radius:8px; padding:12px 14px; min-height:80px; }
   section h2 { margin:0 0 8px; font-size:12px; text-transform:uppercase;
@@ -53,27 +59,116 @@
   .tabs { display:flex; gap:10px; margin-bottom:8px; }
   .tabs a { color:var(--dim); cursor:pointer; }
   .tabs a.active { color:var(--accent); border-bottom:1px solid var(--accent); }
-  .dashboard-tabs { display:flex; gap:10px; padding:10px 20px 0; border-bottom:1px solid var(--border); }
+  .dashboard-tabs { display:flex; gap:10px; padding:10px 20px 0; border-bottom:1px solid var(--border); flex-shrink:0; }
   .dashboard-tabs button { border:0; border-bottom:1px solid transparent; border-radius:0;
           background:transparent; color:var(--dim); padding:5px 0 8px; }
   .dashboard-tabs button.active { color:var(--accent); border-bottom-color:var(--accent); }
   .wide { grid-column:1 / -1; }
   section[hidden] { display:none !important; }
-  .chat-shell { display:grid; grid-template-columns:minmax(0, 1.35fr) minmax(320px, 0.65fr); gap:12px; }
-  .chat-pane { display:flex; flex-direction:column; gap:10px; min-width:0; }
-  .chat-panel { background:var(--bg); border:1px solid var(--border); border-radius:6px; padding:10px; }
-  .chat-controls { display:flex; gap:10px; align-items:end; flex-wrap:wrap; }
-  .chat-controls label { display:flex; flex-direction:column; gap:4px; color:var(--dim); }
-  .chat-controls select { min-width:220px; }
-  .chat-history { display:flex; flex-direction:column; gap:8px; min-height:220px; max-height:420px; overflow:auto; }
-  .chat-message { border:1px solid #21262d; border-radius:6px; padding:8px 10px; background:#10151d; }
-  .chat-role { color:var(--dim); font-size:11px; text-transform:uppercase; letter-spacing:.06em; margin-bottom:4px; }
-  .chat-role-user { color:var(--accent); }
-  .chat-role-assistant { color:var(--ok); }
-  .chat-role-error { color:var(--bad); }
-  .chat-compose { display:flex; flex-direction:column; gap:8px; }
-  .chat-compose textarea { min-height:112px; resize:vertical; width:100%; }
-  .chat-status { color:var(--dim); font-size:12px; }
+  section.chat-section {
+    padding:0; border:0; border-radius:0; background:var(--bg); min-height:0;
+  }
+  body.chat-tab-active section.chat-section {
+    flex:1; display:flex !important; flex-direction:column; min-height:0;
+  }
+  .chat-app {
+    display:grid; grid-template-columns:260px minmax(0, 1fr); gap:0;
+    flex:1; min-height:0; overflow:hidden; background:var(--bg);
+  }
+  .chat-sidebar {
+    display:flex; flex-direction:column; min-height:0;
+    border-right:1px solid var(--border); background:var(--panel);
+  }
+  .chat-new-btn {
+    margin:12px; width:calc(100% - 24px); text-align:left;
+    border:1px solid var(--border); border-radius:8px; padding:10px 12px;
+    background:transparent; color:var(--fg);
+  }
+  .chat-new-btn:hover { background:#10151d; border-color:var(--accent); }
+  .chat-session-list {
+    flex:1; overflow:auto; padding:0 8px 12px; display:flex; flex-direction:column; gap:2px;
+  }
+  .chat-session-list.empty-state {
+    justify-content:center; align-items:center; color:var(--dim); font-style:italic;
+    padding:24px 12px;
+  }
+  .chat-session-item {
+    position:relative; display:block; width:100%; text-align:left;
+    padding:10px 32px 10px 12px; border:1px solid transparent; border-radius:8px;
+    background:transparent; color:var(--fg); cursor:pointer;
+  }
+  .chat-session-item:hover { background:#10151d; }
+  .chat-session-item.active { background:#10151d; border-color:#30363d; }
+  .chat-session-title {
+    font-size:13px; white-space:nowrap; overflow:hidden; text-overflow:ellipsis;
+  }
+  .chat-session-meta {
+    margin-top:3px; font-size:11px; color:var(--dim);
+    white-space:nowrap; overflow:hidden; text-overflow:ellipsis;
+  }
+  .chat-session-delete {
+    position:absolute; top:50%; right:6px; transform:translateY(-50%);
+    padding:2px 6px; min-width:0; border:0; border-radius:4px;
+    background:transparent; color:var(--dim); line-height:1.2; opacity:0;
+  }
+  .chat-session-item:hover .chat-session-delete,
+  .chat-session-item.active .chat-session-delete { opacity:1; }
+  .chat-session-delete:hover { color:var(--bad); background:#1a1012; }
+  .chat-main { display:flex; flex-direction:column; min-height:0; min-width:0; }
+  .chat-toolbar {
+    display:flex; gap:12px; align-items:center; flex-shrink:0;
+    padding:10px 16px; border-bottom:1px solid var(--border); background:var(--panel);
+  }
+  .chat-toolbar label {
+    display:flex; align-items:center; gap:8px; color:var(--dim); margin:0;
+  }
+  .chat-toolbar select { min-width:220px; max-width:min(420px, 50vw); }
+  .chat-status { color:var(--dim); font-size:12px; margin-left:auto; }
+  .chat-messages {
+    flex:1; overflow:auto; padding:24px 16px; min-height:0;
+  }
+  .chat-messages-inner {
+    max-width:768px; margin:0 auto; display:flex; flex-direction:column; gap:20px;
+  }
+  .chat-messages.empty .chat-messages-inner {
+    min-height:100%; justify-content:center; align-items:center;
+    color:var(--dim); font-size:14px;
+  }
+  .chat-row { display:flex; width:100%; }
+  .chat-row.user { justify-content:flex-end; }
+  .chat-row.assistant, .chat-row.error { justify-content:flex-start; }
+  .chat-bubble {
+    max-width:85%; padding:12px 14px; border-radius:16px; line-height:1.55;
+    white-space:pre-wrap; word-break:break-word; font-size:13px;
+  }
+  .chat-bubble.user {
+    background:#1f3a5f; border:1px solid #264a73; border-bottom-right-radius:4px;
+  }
+  .chat-bubble.assistant {
+    background:transparent; border:0; padding-left:0; padding-right:0; max-width:100%;
+  }
+  .chat-bubble.error {
+    background:#1a1012; border:1px solid #5c2020; color:#ffb4b4; border-bottom-left-radius:4px;
+  }
+  .chat-compose-wrap {
+    flex-shrink:0; padding:12px 16px 16px; border-top:1px solid var(--border);
+    background:var(--panel);
+  }
+  .chat-compose {
+    display:flex; gap:8px; align-items:flex-end; max-width:768px; margin:0 auto;
+    padding:10px 12px; border:1px solid var(--border); border-radius:16px;
+    background:var(--bg);
+  }
+  .chat-compose:focus-within { border-color:var(--accent); }
+  .chat-compose textarea {
+    flex:1; min-height:24px; max-height:200px; resize:none; width:auto;
+    border:0; background:transparent; padding:2px 0; outline:none;
+  }
+  .chat-compose button {
+    flex-shrink:0; min-width:36px; height:36px; padding:0;
+    border-radius:8px; border:1px solid var(--border);
+  }
+  .chat-compose button:disabled { opacity:.45; cursor:not-allowed; }
   .console {
     background:var(--bg); border:1px solid var(--border); border-radius:6px;
     min-height:160px; max-height:280px; overflow:auto; padding:7px 9px;
@@ -111,27 +206,27 @@
   <section data-tab="overview"><h2>Nodes &amp; coverage</h2><div id="nodes" class="empty">loading…</div></section>
   <section data-tab="overview"><h2>Model usage (RPM)</h2><div id="stats" class="empty">loading…</div></section>
   <section data-tab="overview" class="wide"><h2>Call wall</h2><div id="call-wall" class="empty">loading...</div></section>
-  <section data-tab="chat" class="wide">
-    <h2>Chat / inference</h2>
-    <div class="chat-shell">
-      <div class="chat-pane">
-        <div class="chat-panel chat-controls">
+  <section data-tab="chat" class="wide chat-section">
+    <div class="chat-app">
+      <aside class="chat-sidebar">
+        <button type="button" class="chat-new-btn" onclick="createNewChatSession()">+ New chat</button>
+        <div id="chat-session-list" class="chat-session-list empty-state">No chats yet</div>
+      </aside>
+      <div class="chat-main">
+        <div class="chat-toolbar">
           <label>Model
             <select id="chat-model" onchange="selectChatModel(this.value)"></select>
           </label>
-          <button class="small" onclick="clearChatHistory()">clear history</button>
-        </div>
-        <div class="chat-panel chat-compose">
-          <textarea id="chat-prompt" placeholder="Ask a question or describe the task"></textarea>
-          <div class="form-row">
-            <button onclick="sendChat()" id="chat-send">Send</button>
-          </div>
-        </div>
-      </div>
-      <div class="chat-pane">
-        <div class="chat-panel">
           <div id="chat-status" class="chat-status">select a model to start</div>
-          <div id="chat-history" class="chat-history empty">no messages yet</div>
+        </div>
+        <div id="chat-history" class="chat-messages empty">
+          <div class="chat-messages-inner">Send a message to start this conversation.</div>
+        </div>
+        <div class="chat-compose-wrap">
+          <div class="chat-compose">
+            <textarea id="chat-prompt" placeholder="Message…" rows="1" aria-label="Message"></textarea>
+            <button type="button" onclick="sendChat()" id="chat-send" title="Send (Enter)">↑</button>
+          </div>
         </div>
       </div>
     </div>
@@ -604,17 +699,214 @@ let lastStats = null;
 let availableModels = [];
 let chatHistory = [];
 let chatBusy = false;
+let chatSessions = [];
+let activeChatSessionId = "";
 let selectedChatModel = localStorage.getItem("meshnet_chat_model") || "";
+const CHAT_SESSIONS_KEY = "meshnet_chat_sessions_v1";
+const CHAT_ACTIVE_SESSION_KEY = "meshnet_chat_active_session_v1";
+const CHAT_SESSIONS_LIMIT = 50;
+
+function newChatSessionId() {
+  if (window.crypto && crypto.randomUUID) return crypto.randomUUID();
+  return "chat-" + Date.now().toString(36) + "-" + Math.random().toString(36).slice(2, 8);
+}
+
+function loadChatSessionsStore() {
+  try {
+    const raw = localStorage.getItem(CHAT_SESSIONS_KEY);
+    const parsed = raw ? JSON.parse(raw) : [];
+    return Array.isArray(parsed) ? parsed : [];
+  } catch {
+    return [];
+  }
+}
+
+function saveChatSessionsStore() {
+  localStorage.setItem(CHAT_SESSIONS_KEY, JSON.stringify(chatSessions));
+  if (activeChatSessionId) {
+    localStorage.setItem(CHAT_ACTIVE_SESSION_KEY, activeChatSessionId);
+  }
+}
+
+function chatSessionTitle(session) {
+  const firstUser = (session.messages || []).find(msg => msg.role === "user");
+  if (!firstUser || !firstUser.content) return "New chat";
+  const text = String(firstUser.content).trim().replace(/\s+/g, " ");
+  return text.length > 42 ? text.slice(0, 42) + "…" : text;
+}
+
+function formatSessionTime(iso) {
+  if (!iso) return "";
+  const date = new Date(iso);
+  if (Number.isNaN(date.getTime())) return "";
+  const now = new Date();
+  const sameDay = date.toDateString() === now.toDateString();
+  if (sameDay) return date.toLocaleTimeString([], { hour: "2-digit", minute: "2-digit" });
+  return date.toLocaleDateString([], { month: "short", day: "numeric" });
+}
+
+function getActiveChatSession() {
+  return chatSessions.find(session => session.id === activeChatSessionId) || null;
+}
+
+function persistActiveChatSession() {
+  const session = getActiveChatSession();
+  if (!session) return;
+  session.messages = chatHistory.slice();
+  session.model = selectedChatModel || session.model || "";
+  session.title = chatSessionTitle(session);
+  session.updatedAt = new Date().toISOString();
+  chatSessions.sort((a, b) => String(b.updatedAt).localeCompare(String(a.updatedAt)));
+  if (chatSessions.length > CHAT_SESSIONS_LIMIT) {
+    chatSessions = chatSessions.slice(0, CHAT_SESSIONS_LIMIT);
+    if (!chatSessions.some(item => item.id === activeChatSessionId)) {
+      activeChatSessionId = chatSessions[0].id;
+      chatHistory = chatSessions[0].messages.slice();
+    }
+  }
+  saveChatSessionsStore();
+  renderChatSessionList();
+}
+
+function clearChatPrompt() {
+  const promptEl = $("chat-prompt");
+  if (!promptEl) return;
+  promptEl.value = "";
+  promptEl.style.height = "auto";
+}
+
+function createNewChatSession() {
+  if (chatBusy) return;
+  const session = {
+    id: newChatSessionId(),
+    title: "New chat",
+    model: selectedChatModel || "",
+    messages: [],
+    createdAt: new Date().toISOString(),
+    updatedAt: new Date().toISOString(),
+  };
+  chatSessions.unshift(session);
+  activeChatSessionId = session.id;
+  chatHistory = [];
+  clearChatPrompt();
+  saveChatSessionsStore();
+  renderChatSessionList();
+  renderChatHistory();
+  renderChatAuthHint();
+  const promptEl = $("chat-prompt");
+  if (promptEl) promptEl.focus();
+}
+
+function selectChatSession(sessionId) {
+  if (chatBusy) return;
+  const session = chatSessions.find(item => item.id === sessionId);
+  if (!session) return;
+  if (sessionId === activeChatSessionId) return;
+  activeChatSessionId = session.id;
+  chatHistory = (session.messages || []).slice();
+  clearChatPrompt();
+  if (session.model) {
+    selectedChatModel = session.model;
+    localStorage.setItem("meshnet_chat_model", selectedChatModel);
+    const select = $("chat-model");
+    if (select) select.value = selectedChatModel;
+  }
+  localStorage.setItem(CHAT_ACTIVE_SESSION_KEY, activeChatSessionId);
+  renderChatSessionList();
+  renderChatHistory();
+  renderChatAuthHint();
+}
+
+function deleteChatSession(sessionId, event) {
+  if (event) {
+    event.preventDefault();
+    event.stopPropagation();
+  }
+  if (chatBusy) return;
+  const index = chatSessions.findIndex(item => item.id === sessionId);
+  if (index < 0) return;
+  chatSessions.splice(index, 1);
+  if (activeChatSessionId === sessionId) {
+    if (chatSessions.length) {
+      activeChatSessionId = chatSessions[0].id;
+      chatHistory = (chatSessions[0].messages || []).slice();
+      clearChatPrompt();
+      if (chatSessions[0].model) {
+        selectedChatModel = chatSessions[0].model;
+        localStorage.setItem("meshnet_chat_model", selectedChatModel);
+      }
+    } else {
+      saveChatSessionsStore();
+      createNewChatSession();
+      return;
+    }
+  }
+  saveChatSessionsStore();
+  renderChatSessionList();
+  renderChatHistory();
+  renderChatModels();
+}
+
+function initChatSessions() {
+  chatSessions = loadChatSessionsStore();
+  activeChatSessionId = localStorage.getItem(CHAT_ACTIVE_SESSION_KEY) || "";
+  const active = chatSessions.find(session => session.id === activeChatSessionId);
+  if (!active) {
+    if (chatSessions.length) {
+      activeChatSessionId = chatSessions[0].id;
+      chatHistory = (chatSessions[0].messages || []).slice();
+      if (chatSessions[0].model) selectedChatModel = chatSessions[0].model;
+    } else {
+      createNewChatSession();
+      return;
+    }
+  } else {
+    chatHistory = (active.messages || []).slice();
+    if (active.model) selectedChatModel = active.model;
+  }
+  renderChatSessionList();
+  renderChatHistory();
+}
+
+function renderChatSessionList() {
+  const list = $("chat-session-list");
+  if (!list) return;
+  if (!chatSessions.length) {
+    list.className = "chat-session-list empty-state";
+    list.innerHTML = "No chats yet";
+    return;
+  }
+  list.className = "chat-session-list";
+  list.innerHTML = chatSessions.map(session => {
+    const active = session.id === activeChatSessionId ? " active" : "";
+    const title = esc(chatSessionTitle(session));
+    const when = esc(formatSessionTime(session.updatedAt || session.createdAt));
+    const id = JSON.stringify(session.id);
+    return `<div class="chat-session-item${active}" role="button" tabindex="0"` +
+      ` onclick="selectChatSession(${id})"` +
+      ` onkeydown="if(event.key==='Enter'||event.key===' '){event.preventDefault();selectChatSession(${id});}">` +
+      `<div class="chat-session-title">${title}</div>` +
+      (when ? `<div class="chat-session-meta">${when}</div>` : "") +
+      `<button type="button" class="chat-session-delete" title="Delete chat"` +
+      ` onclick="deleteChatSession(${id}, event)">×</button>` +
+      `</div>`;
+  }).join("");
+}
 
 function switchDashboardTab(name) {
   if (name === "admin" && !isAdmin) name = "overview";
   if (name === "billing" && !isLoggedIn) name = "overview";
   dashboardTab = name;
+  document.body.classList.toggle("chat-tab-active", name === "chat");
   updateSectionVisibility();
   for (const tabName of ["overview", "chat", "billing", "admin"]) {
     const button = $("tab-" + tabName);
     if (button) button.classList.toggle("active", tabName === dashboardTab);
   }
+  if (name === "chat") {
+    const promptEl = $("chat-prompt");
+    if (promptEl) promptEl.focus();
+  }
 }
 
 function updateSectionVisibility() {
@@ -632,18 +924,18 @@ function renderChatStatus(text) {
 
 function renderChatHistory() {
   const history = $("chat-history");
+  if (!history) return;
   if (!chatHistory.length) {
-    history.classList.add("empty");
-    history.innerHTML = "no messages yet";
+    history.className = "chat-messages empty";
+    history.innerHTML = '<div class="chat-messages-inner">Send a message to start this conversation.</div>';
     return;
   }
-  history.classList.remove("empty");
-  history.innerHTML = chatHistory.map(msg => {
-    const roleClass = msg.role === "user" ? "chat-role-user" : msg.role === "assistant" ? "chat-role-assistant" : "chat-role-error";
-    const label = msg.role === "user" ? "user" : msg.role === "assistant" ? "assistant" : "error";
-    const meta = msg.model ? ` <span class="dim">· ${esc(short(msg.model, 24))}</span>` : "";
-    return `<div class="chat-message"><div class="chat-role ${roleClass}">${label}${meta}</div><div>${esc(msg.content)}</div></div>`;
+  history.className = "chat-messages";
+  const rows = chatHistory.map(msg => {
+    const role = msg.role === "user" ? "user" : msg.role === "assistant" ? "assistant" : "error";
+    return `<div class="chat-row ${role}"><div class="chat-bubble ${role}">${esc(msg.content)}</div></div>`;
   }).join("");
+  history.innerHTML = `<div class="chat-messages-inner">${rows}</div>`;
   history.scrollTop = history.scrollHeight;
 }
 
@@ -674,12 +966,13 @@ function renderChatModels() {
 function selectChatModel(value) {
   selectedChatModel = value || "";
   localStorage.setItem("meshnet_chat_model", selectedChatModel);
-}
-
-function clearChatHistory() {
-  chatHistory = [];
-  renderChatHistory();
-  renderChatStatus("history cleared");
+  const session = getActiveChatSession();
+  if (session) {
+    session.model = selectedChatModel;
+    session.updatedAt = new Date().toISOString();
+    saveChatSessionsStore();
+    renderChatSessionList();
+  }
 }
 
 function chatAuthToken() {
@@ -935,8 +1228,10 @@ async function sendChat() {
   chatBusy = true;
   $("chat-send").disabled = true;
   promptEl.value = "";
+  promptEl.style.height = "auto";
   chatHistory.push({ role: "user", content: prompt, model: selectedChatModel });
   renderChatHistory();
+  persistActiveChatSession();
   renderChatStatus("sending request…");
   const r = await apiCall("/v1/chat/completions", "POST", body, bearerToken);
   chatBusy = false;
@@ -947,6 +1242,7 @@ async function sendChat() {
       : "request failed";
     chatHistory.push({ role: "error", content: error, model: selectedChatModel });
     renderChatHistory();
+    persistActiveChatSession();
     renderChatStatus(error);
     promptEl.focus();
     return;
@@ -959,12 +1255,29 @@ async function sendChat() {
     model: selectedChatModel,
   });
   renderChatHistory();
+  persistActiveChatSession();
   renderChatStatus(usage
     ? `done: ${usage.total_tokens ?? "?"} tokens`
     : "done");
   promptEl.focus();
 }
 
+function bindChatPromptShortcuts() {
+  const promptEl = $("chat-prompt");
+  if (!promptEl || promptEl.dataset.bound === "1") return;
+  promptEl.dataset.bound = "1";
+  promptEl.addEventListener("keydown", event => {
+    if (event.key === "Enter" && !event.shiftKey) {
+      event.preventDefault();
+      sendChat();
+    }
+  });
+  promptEl.addEventListener("input", () => {
+    promptEl.style.height = "auto";
+    promptEl.style.height = Math.min(promptEl.scrollHeight, 200) + "px";
+  });
+}
+
 async function renderAdminPanel() {
   const r = await apiCall("/v1/admin/accounts");
   if (!r.ok) { setAdminMode(false); return; }
@@ -1034,6 +1347,8 @@ async function refresh() {
   $("refreshed").textContent = "refreshed " + new Date().toLocaleTimeString();
 }
 refresh();
+initChatSessions();
+bindChatPromptShortcuts();
 renderAccountPanel();
 renderChatModels();
 renderChatHistory();
diff --git a/packages/tracker/meshnet_tracker/server.py b/packages/tracker/meshnet_tracker/server.py
index 1ea498d..d28ed8a 100644
--- a/packages/tracker/meshnet_tracker/server.py
+++ b/packages/tracker/meshnet_tracker/server.py
@@ -4864,6 +4864,7 @@ class _TrackerHandler(http.server.BaseHTTPRequestHandler):
             "model": resolved_name,
             "model_layers_end": required_end,
             "peers": peers,
+            "bytes_per_layer": _preset_bytes_per_layer(preset),
             "model_sources": self._model_sources(
                 resolved_name,
                 preset,
diff --git a/tests/test_node_startup.py b/tests/test_node_startup.py
index 3a22a51..fdf09a9 100644
--- a/tests/test_node_startup.py
+++ b/tests/test_node_startup.py
@@ -1646,6 +1646,106 @@ def test_preset_model_startup_honors_pinned_shard_range(tmp_path, monkeypatch):
         tracker.stop()
 
 
+def test_preset_startup_rejects_pinned_shard_above_memory_budget(tmp_path, monkeypatch):
+    """Pinned layer ranges that exceed the node memory budget fail before model load."""
+    import meshnet_node.startup as startup_mod
+
+    monkeypatch.setattr(
+        startup_mod,
+        "detect_hardware",
+        lambda: {"device": "cpu", "gpu_name": None, "vram_mb": 0, "ram_mb": 8 * 1024},
+    )
+
+    tracker = TrackerServer(model_presets={
+        "big-model": {
+            "layers_start": 0,
+            "layers_end": 39,
+            "hf_repo": "org/big-model",
+            "bytes_per_layer": {"bfloat16": 2 * 1024 * 1024 * 1024},
+        },
+    })
+    tracker_port = tracker.start()
+    tracker_url = f"http://127.0.0.1:{tracker_port}"
+    try:
+        with pytest.raises(ValueError, match="Pinned shard layers 0–39"):
+            run_startup(
+                tracker_url=tracker_url,
+                model="big-model",
+                shard_start=0,
+                shard_end=39,
+                wallet_path=tmp_path / "wallet.json",
+                cache_dir=tmp_path / "shards",
+            )
+    finally:
+        tracker.stop()
+
+
+def test_preset_model_with_hf_repo_loads_torch_backend(tmp_path, monkeypatch, capsys):
+    """Named presets that advertise hf_repo must load TorchNodeServer, not the stub server."""
+    import meshnet_node.startup as startup_mod
+
+    class FakeBackend:
+        total_layers = 16
+
+    torch_calls: list[dict] = []
+
+    class FakeTorchNodeServer:
+        def __init__(self, **kwargs):
+            torch_calls.append(kwargs)
+            self.backend = FakeBackend()
+            self.port = None
+            self.chat_completion_count = 0
+            self.tracker_node_id = None
+
+        def start(self):
+            self.port = 7002
+            return self.port
+
+        def stop(self):
+            pass
+
+    monkeypatch.setattr(
+        startup_mod,
+        "detect_hardware",
+        lambda: {"device": "cpu", "gpu_name": None, "vram_mb": 0, "ram_mb": 16 * 1024},
+    )
+    monkeypatch.setattr(startup_mod, "TorchNodeServer", FakeTorchNodeServer)
+    monkeypatch.setattr(startup_mod, "StubNodeServer", lambda **_kw: (_ for _ in ()).throw(AssertionError("preset with hf_repo must not use StubNodeServer")))
+
+    model_dir = tmp_path / "node-shards" / "tiny-llama"
+    model_dir.mkdir(parents=True)
+    (model_dir / "config.json").write_text('{"num_hidden_layers": 16}')
+    monkeypatch.setattr(startup_mod, "download_shard", lambda *_a, **_kw: model_dir)
+
+    tracker = TrackerServer(model_presets={
+        "tiny-llama": {"layers_start": 0, "layers_end": 15, "hf_repo": "org/tiny-llama-shards"}
+    })
+    tracker_port = tracker.start()
+    tracker_url = f"http://127.0.0.1:{tracker_port}"
+    try:
+        node = run_startup(
+            tracker_url=tracker_url,
+            model="tiny-llama",
+            wallet_path=tmp_path / "wallet.json",
+            cache_dir=tmp_path / "node-shards",
+        )
+        try:
+            assert len(torch_calls) == 1
+            assert torch_calls[0]["model_id"] == "org/tiny-llama-shards"
+            assert torch_calls[0]["cache_dir"] == model_dir
+            output = capsys.readouterr().out
+            assert "Loading real PyTorch model shard..." in output
+            assert "Model ID:     org/tiny-llama-shards" in output
+            network_map = _get_json(f"{tracker_url}/v1/network/map")
+            registered = network_map["nodes"][0]
+            assert registered["hf_repo"] == "org/tiny-llama-shards"
+            assert registered["num_layers"] == 16
+        finally:
+            node.stop()
+    finally:
+        tracker.stop()
+
+
 def test_torch_startup_retries_registration_when_tracker_unreachable(
     tmp_path,
     monkeypatch,
diff --git a/tests/test_real_model_backend.py b/tests/test_real_model_backend.py
index 656c55f..de8e5e5 100644
--- a/tests/test_real_model_backend.py
+++ b/tests/test_real_model_backend.py
@@ -17,6 +17,7 @@ from meshnet_node.model_backend import (
     TensorPayload,
     TorchModelShard,
     _call_layer,
+    _checkpoint_tensor_name_for_model,
     _load_partial_model_from_snapshot,
     _should_partial_materialize_shard,
     _decoder_attention_mask,
@@ -429,7 +430,7 @@ def test_partial_materialize_guard_requires_local_non_full_non_quantized_snapsho
         39,
         total_layers_hint=40,
         uses_quantized_weights=False,
-    ) is False
+    ) is True
     assert _should_partial_materialize_shard(
         str(snapshot_dir),
         4,
@@ -446,6 +447,118 @@ def test_partial_materialize_guard_requires_local_non_full_non_quantized_snapsho
     ) is False
 
 
+def test_checkpoint_tensor_name_remapped_for_text_only_causal_lm():
+    class TextOnlyModel:
+        def __init__(self):
+            self.model = types.SimpleNamespace(layers=[])
+
+    model = TextOnlyModel()
+    assert _checkpoint_tensor_name_for_model(
+        model,
+        "model.language_model.layers.0.mlp.gate.weight",
+    ) == "model.layers.0.mlp.gate.weight"
+    assert _checkpoint_tensor_name_for_model(
+        model,
+        "model.language_model.embed_tokens.weight",
+    ) == "model.embed_tokens.weight"
+
+
+def test_checkpoint_tensor_name_kept_for_multimodal_backbone():
+    class MultimodalModel:
+        def __init__(self):
+            self.model = types.SimpleNamespace(language_model=types.SimpleNamespace())
+
+    model = MultimodalModel()
+    name = "model.language_model.layers.0.mlp.gate.weight"
+    assert _checkpoint_tensor_name_for_model(model, name) == name
+
+
+def test_partial_snapshot_loader_remaps_language_model_checkpoint_keys(tmp_path):
+    snapshot_dir = tmp_path / "snapshot"
+    snapshot_dir.mkdir()
+    (snapshot_dir / "config.json").write_text(json.dumps({
+        "text_config": {"num_hidden_layers": 3},
+    }))
+    (snapshot_dir / "model.safetensors.index.json").write_text(json.dumps({
+        "weight_map": {
+            "model.language_model.layers.1.self_attn.q_proj.weight": "shard-2.safetensors",
+        }
+    }))
+    (snapshot_dir / "shard-2.safetensors").write_bytes(b"stub")
+
+    class FakeModule:
+        def __init__(self):
+            self.to_calls = []
+
+        def to(self, device):
+            self.to_calls.append(device)
+            return self
+
+    class FakeModel:
+        def __init__(self):
+            self.model = types.SimpleNamespace(
+                layers=[FakeModule(), FakeModule(), FakeModule()],
+                rotary_emb=FakeModule(),
+            )
+
+        def tie_weights(self):
+            pass
+
+    class AutoConfigStub:
+        @staticmethod
+        def from_pretrained(model_id):
+            return types.SimpleNamespace(
+                text_config=types.SimpleNamespace(num_hidden_layers=3),
+                get_text_config=lambda: types.SimpleNamespace(num_hidden_layers=3),
+            )
+
+    class AutoModelStub:
+        @staticmethod
+        def from_config(cfg, torch_dtype=None):
+            return FakeModel()
+
+    set_calls = []
+
+    def fake_set_tensor(module, tensor_name, device, value=None, dtype=None):
+        set_calls.append(tensor_name)
+
+    class FakeSafeOpen:
+        def __init__(self, filename, framework, device):
+            self.filename = Path(filename).name
+
+        def __enter__(self):
+            return self
+
+        def __exit__(self, exc_type, exc, tb):
+            return False
+
+        def get_tensor(self, tensor_name):
+            return tensor_name
+
+    class UnusedContext:
+        def __enter__(self):
+            return None
+
+        def __exit__(self, exc_type, exc, tb):
+            return False
+
+    _load_partial_model_from_snapshot(
+        AutoConfigStub,
+        AutoModelStub,
+        types.SimpleNamespace(),
+        str(snapshot_dir),
+        1,
+        1,
+        "bf16",
+        "cpu:0",
+        init_empty_weights_fn=UnusedContext,
+        set_tensor_fn=fake_set_tensor,
+        safe_open_fn=FakeSafeOpen,
+    )
+
+    assert set_calls == ["model.layers.1.self_attn.q_proj.weight"]
+
+
 def test_partial_snapshot_loader_materializes_only_assigned_tensors(tmp_path):
     snapshot_dir = tmp_path / "snapshot"
     snapshot_dir.mkdir()