diff --git a/packages/iios-service/src/messaging/message.gateway.ts b/packages/iios-service/src/messaging/message.gateway.ts
index 2967640..9501443 100644
--- a/packages/iios-service/src/messaging/message.gateway.ts
+++ b/packages/iios-service/src/messaging/message.gateway.ts
@@ -66,11 +66,20 @@ export class MessageGateway implements OnGatewayInit, OnGatewayConnection {
   }
 
   @SubscribeMessage('open_thread')
-  async openThread(@ConnectedSocket() client: Socket, @MessageBody() body: { threadId?: string; membership?: string; creatorRole?: string }) {
+  async openThread(@ConnectedSocket() client: Socket, @MessageBody() body: { threadId?: string; membership?: string; creatorRole?: string; subject?: string }) {
     const { principal } = client.data as SocketState;
-    const result = await this.messages.openThread(body?.threadId ?? null, principal, { membership: body?.membership, creatorRole: body?.creatorRole });
-    await client.join(result.threadId);
-    return result;
+    try {
+      const result = await this.messages.openThread(body?.threadId ?? null, principal, {
+        membership: body?.membership,
+        creatorRole: body?.creatorRole,
+        subject: body?.subject,
+      });
+      await client.join(result.threadId);
+      return result;
+    } catch (err) {
+      // Fail to an ACK'd error instead of throwing (which never acks → client hangs on "loading").
+      return { error: (err as Error).message ?? 'could not open the conversation' };
+    }
   }
 
   @SubscribeMessage('add_participant')
diff --git a/packages/iios-service/src/messaging/message.service.ts b/packages/iios-service/src/messaging/message.service.ts
index 4dfa4af..33b4278 100644
--- a/packages/iios-service/src/messaging/message.service.ts
+++ b/packages/iios-service/src/messaging/message.service.ts
@@ -59,17 +59,18 @@ export class MessageService {
    * for a group. Opening an existing thread is a GOVERNED join: only an existing member may
    * re-open it (policy `iios.thread.join`) — new members enter via addParticipant.
    */
-  async openThread(threadId: string | null, principal: MessagePrincipal, opts?: { membership?: string; creatorRole?: string }): Promise<OpenThreadResult> {
+  async openThread(threadId: string | null, principal: MessagePrincipal, opts?: { membership?: string; creatorRole?: string; subject?: string }): Promise<OpenThreadResult> {
     if (!threadId) {
       await decideOrThrow(this.ports, { action: 'iios.thread.create', scope: principal });
       const scope = await this.actors.resolveScope(principal);
       const actor = await this.actors.resolveActor(scope.id, principal);
-      // `membership` + `creatorRole` are generic, app-supplied thread attributes — the kernel
-      // stores/echoes them but never branches on their chat meaning (that lives in policy + app).
+      // `membership`/`creatorRole`/`subject` are generic, app-supplied thread attributes — the
+      // kernel stores/echoes them but never branches on their chat meaning (that lives in policy + app).
       const thread = await this.prisma.iiosThread.create({
         data: {
           scopeId: scope.id,
           createdByActorId: actor.id,
+          subject: opts?.subject?.trim() || undefined,
           metadata: opts?.membership ? ({ membership: opts.membership } as Prisma.InputJsonValue) : undefined,
         },
       });
diff --git a/packages/iios-service/src/threads/threads.controller.ts b/packages/iios-service/src/threads/threads.controller.ts
index 3e4c95e..02e5e0b 100644
--- a/packages/iios-service/src/threads/threads.controller.ts
+++ b/packages/iios-service/src/threads/threads.controller.ts
@@ -28,11 +28,11 @@ export class ThreadsController {
     return this.messages.listThreads(this.principal(auth));
   }
 
-  /** Create a thread; `membership`/`creatorRole` are opaque, app-supplied thread attributes the kernel stores but never interprets. */
+  /** Create a thread; `membership`/`creatorRole`/`subject` are opaque, app-supplied attributes the kernel stores but never interprets. */
   @Post()
   @HttpCode(201)
-  async createThread(@Body() body: { membership?: string; creatorRole?: string }, @Headers('authorization') auth?: string) {
-    return this.messages.openThread(null, this.principal(auth), { membership: body?.membership, creatorRole: body?.creatorRole });
+  async createThread(@Body() body: { membership?: string; creatorRole?: string; subject?: string }, @Headers('authorization') auth?: string) {
+    return this.messages.openThread(null, this.principal(auth), { membership: body?.membership, creatorRole: body?.creatorRole, subject: body?.subject });
   }
 
   /** Governed membership: add a user (by userId) to a thread — policy enforces DM cap / roles. */
diff --git a/scripts/vitest-global-setup.mjs b/scripts/vitest-global-setup.mjs
new file mode 100644
index 0000000..6d8dfdd
--- /dev/null
+++ b/scripts/vitest-global-setup.mjs
@@ -0,0 +1,20 @@
+import { execSync } from 'node:child_process';
+
+// Tests TRUNCATE between cases, so they MUST NOT touch the dev database. Run them
+// against an isolated `iios_test` DB (created + migrated here, once, before the suite).
+const TEST_URL = 'postgresql://iios:iios@localhost:5434/iios_test?schema=public';
+
+export default function setup() {
+  try {
+    execSync(`docker exec iios-db psql -U iios -d postgres -c "CREATE DATABASE iios_test"`, { stdio: 'pipe' });
+  } catch (e) {
+    const msg = String(e.stderr ?? e.stdout ?? e);
+    if (!/already exists/i.test(msg)) {
+      console.warn(`[vitest] could not create iios_test (is the iios-db container up?): ${msg.slice(0, 160)}`);
+    }
+  }
+  execSync('pnpm --filter @insignia/iios-service exec prisma migrate deploy', {
+    stdio: 'inherit',
+    env: { ...process.env, DATABASE_URL: TEST_URL },
+  });
+}
diff --git a/vitest.config.ts b/vitest.config.ts
index 2245582..995eb6f 100644
--- a/vitest.config.ts
+++ b/vitest.config.ts
@@ -15,9 +15,13 @@ export default defineConfig({
   },
   test: {
     include: ['packages/**/src/**/*.{test,spec}.ts', 'test/**/*.{test,spec}.ts'],
-    // DB-backed specs share one Postgres and TRUNCATE between tests. Run every
-    // file in a single worker process, sequentially, so there is no cross-file
-    // race on the shared database.
+    // DB-backed specs TRUNCATE between tests, so they run against an ISOLATED
+    // `iios_test` database (created + migrated by the global setup) — never the dev
+    // DB. This env overrides any DATABASE_URL from the shell.
+    env: { DATABASE_URL: 'postgresql://iios:iios@localhost:5434/iios_test?schema=public' },
+    globalSetup: ['./scripts/vitest-global-setup.mjs'],
+    // Run every file in a single worker process, sequentially, so there is no
+    // cross-file race on the shared database.
     fileParallelism: false,
     sequence: { concurrent: false },
     pool: 'forks',