diff --git a/frontend/package.json b/frontend/package.json
index c43ec99..7c36534 100644
--- a/frontend/package.json
+++ b/frontend/package.json
@@ -1,7 +1,7 @@
 {
   "name": "stackpilot-frontend",
   "private": true,
-  "version": "0.33.0",
+  "version": "0.34.0",
   "type": "module",
   "scripts": {
     "dev": "vite",
diff --git a/frontend/src/components/stacks/LogViewer.tsx b/frontend/src/components/stacks/LogViewer.tsx
index 99e7de4..dff2b7e 100644
--- a/frontend/src/components/stacks/LogViewer.tsx
+++ b/frontend/src/components/stacks/LogViewer.tsx
@@ -1,6 +1,6 @@
-import { useEffect, useRef, useState } from "react";
-import { ArrowDownToLine, Pause, Play } from "lucide-react";
-import { Button } from "@/components/ui";
+import { useEffect, useMemo, useRef, useState } from "react";
+import { ArrowDownToLine, Pause, Play, Search, X } from "lucide-react";
+import { Button, Input } from "@/components/ui";
 import { useAuthStore } from "@/store/auth";
 
 const MAX_LINES = 2000;
@@ -21,11 +21,42 @@ function colorFor(service: string | null): string {
   return serviceColors[h % serviceColors.length];
 }
 
+type Level = "error" | "warn" | "info" | "debug";
+
+const errorRe = /\b(error|err|fatal|fail(?:ed|ure)?|panic|exception|critical|crit)\b/i;
+const warnRe = /\b(warn(?:ing)?|deprecat(?:ed|ion)?)\b/i;
+const debugRe = /\b(debug|trace)\b/i;
+
+function levelFor(line: string): Level {
+  if (errorRe.test(line)) return "error";
+  if (warnRe.test(line)) return "warn";
+  if (debugRe.test(line)) return "debug";
+  return "info";
+}
+
+// Dozzle-style visual coding per severity.
+const levelStyles: Record<Level, { text: string; row: string }> = {
+  error: {
+    text: "text-rose-300",
+    row: "border-l-2 border-rose-500 bg-rose-500/10",
+  },
+  warn: {
+    text: "text-amber-300",
+    row: "border-l-2 border-amber-500 bg-amber-500/10",
+  },
+  info: { text: "text-slate-200", row: "border-l-2 border-transparent" },
+  debug: { text: "text-slate-400", row: "border-l-2 border-transparent" },
+};
+
+type LogLine = { service: string | null; line: string; level: Level };
+
 export function LogViewer({ stackId, agentId }: { stackId: string; agentId?: number }) {
-  const [lines, setLines] = useState<{ service: string | null; line: string }[]>([]);
+  const [lines, setLines] = useState<LogLine[]>([]);
   const [autoScroll, setAutoScroll] = useState(true);
   const [connected, setConnected] = useState(false);
   const [error, setError] = useState<string | null>(null);
+  const [serviceFilter, setServiceFilter] = useState<string>("__all__");
+  const [search, setSearch] = useState("");
   const containerRef = useRef<HTMLDivElement>(null);
   const token = useAuthStore((s) => s.accessToken);
 
@@ -53,7 +84,10 @@ export function LogViewer({ stackId, agentId }: { stackId: string; agentId?: num
         const msg = JSON.parse(ev.data);
         if (msg.type === "log") {
           setLines((prev) => {
-            const next = [...prev, { service: msg.service, line: msg.line }];
+            const next = [
+              ...prev,
+              { service: msg.service, line: msg.line, level: levelFor(msg.line) },
+            ];
             return next.length > MAX_LINES ? next.slice(-MAX_LINES) : next;
           });
         } else if (msg.type === "error") {
@@ -67,14 +101,30 @@ export function LogViewer({ stackId, agentId }: { stackId: string; agentId?: num
     return () => ws.close();
   }, [stackId, agentId, token]);
 
+  // Unique services seen so far, for the container filter.
+  const services = useMemo(() => {
+    const set = new Set<string>();
+    for (const l of lines) if (l.service) set.add(l.service);
+    return [...set].sort();
+  }, [lines]);
+
+  const filtered = useMemo(() => {
+    const q = search.trim().toLowerCase();
+    return lines.filter((l) => {
+      if (serviceFilter !== "__all__" && l.service !== serviceFilter) return false;
+      if (q && !l.line.toLowerCase().includes(q)) return false;
+      return true;
+    });
+  }, [lines, serviceFilter, search]);
+
   useEffect(() => {
     if (autoScroll && containerRef.current) {
       containerRef.current.scrollTop = containerRef.current.scrollHeight;
     }
-  }, [lines, autoScroll]);
+  }, [filtered, autoScroll]);
 
   const download = () => {
-    const blob = new Blob([lines.map((l) => l.line).join("\n")], {
+    const blob = new Blob([filtered.map((l) => l.line).join("\n")], {
       type: "text/plain",
     });
     const a = document.createElement("a");
@@ -85,15 +135,51 @@ export function LogViewer({ stackId, agentId }: { stackId: string; agentId?: num
 
   return (
     <div className="flex h-full flex-col">
-      <div className="mb-2 flex items-center justify-between">
-        <span className="text-xs text-slate-500">
-          {connected ? (
-            <span className="text-green-500">● live</span>
-          ) : (
-            <span className="text-slate-400">○ disconnected</span>
-          )}
-          <span className="ml-2">{lines.length} lines</span>
-        </span>
+      <div className="mb-2 flex flex-wrap items-center justify-between gap-2">
+        <div className="flex items-center gap-2">
+          <span className="text-xs text-slate-500">
+            {connected ? (
+              <span className="text-green-500">● live</span>
+            ) : (
+              <span className="text-slate-400">○ disconnected</span>
+            )}
+          </span>
+          <select
+            value={serviceFilter}
+            onChange={(e) => setServiceFilter(e.target.value)}
+            className="rounded-lg border border-slate-300 bg-white px-2 py-1.5 text-sm text-slate-900 outline-none focus:border-accent focus:ring-1 focus:ring-accent dark:border-slate-600 dark:bg-slate-800 dark:text-slate-100"
+          >
+            <option value="__all__">All containers</option>
+            {services.map((s) => (
+              <option key={s} value={s}>
+                {s}
+              </option>
+            ))}
+          </select>
+          <div className="relative">
+            <Search className="pointer-events-none absolute left-2 top-1/2 h-4 w-4 -translate-y-1/2 text-slate-400" />
+            <Input
+              value={search}
+              onChange={(e) => setSearch(e.target.value)}
+              placeholder="Filter…"
+              className="w-44 py-1.5 pl-8 pr-7"
+            />
+            {search && (
+              <button
+                onClick={() => setSearch("")}
+                className="absolute right-2 top-1/2 -translate-y-1/2 text-slate-400 hover:text-slate-200"
+                aria-label="Clear filter"
+              >
+                <X className="h-4 w-4" />
+              </button>
+            )}
+          </div>
+          <span className="text-xs text-slate-500">
+            {filtered.length === lines.length
+              ? `${lines.length} lines`
+              : `${filtered.length} / ${lines.length} lines`}
+          </span>
+        </div>
         <div className="flex gap-2">
           <Button variant="outline" onClick={() => setAutoScroll((v) => !v)}>
             {autoScroll ? <Pause className="h-4 w-4" /> : <Play className="h-4 w-4" />}
@@ -106,7 +192,7 @@ export function LogViewer({ stackId, agentId }: { stackId: string; agentId?: num
       </div>
       <div
         ref={containerRef}
-        className="flex-1 overflow-auto rounded-lg bg-slate-950 p-3 font-mono text-xs leading-relaxed"
+        className="h-[65vh] overflow-auto rounded-lg bg-slate-950 p-3 font-mono text-xs leading-relaxed"
       >
         {error && (
           <div className="mb-1 whitespace-pre-wrap break-words text-rose-400">
@@ -116,14 +202,23 @@ export function LogViewer({ stackId, agentId }: { stackId: string; agentId?: num
         {lines.length === 0 && !error && (
           <div className="text-slate-500">Waiting for log output…</div>
         )}
-        {lines.map((l, i) => (
-          <div key={i} className="whitespace-pre-wrap break-all">
-            {l.service && (
-              <span className={`mr-2 ${colorFor(l.service)}`}>{l.service}</span>
-            )}
-            <span className="text-slate-200">{l.line}</span>
-          </div>
-        ))}
+        {lines.length > 0 && filtered.length === 0 && !error && (
+          <div className="text-slate-500">No lines match the current filter.</div>
+        )}
+        {filtered.map((l, i) => {
+          const style = levelStyles[l.level];
+          return (
+            <div
+              key={i}
+              className={`whitespace-pre-wrap break-all py-0.5 pl-2 ${style.row}`}
+            >
+              {l.service && (
+                <span className={`mr-2 ${colorFor(l.service)}`}>{l.service}</span>
+              )}
+              <span className={style.text}>{l.line}</span>
+            </div>
+          );
+        })}
       </div>
     </div>
   );