diff --git a/services/mam-api/src/index.js b/services/mam-api/src/index.js
index 1ba708a..01b18b7 100644
--- a/services/mam-api/src/index.js
+++ b/services/mam-api/src/index.js
@@ -32,6 +32,7 @@ import metricsRouter  from './routes/metrics.js';
 import commentsRouter from './routes/comments.js';
 import importsRouter  from './routes/imports.js';
 import { startSchedulerLoop } from './scheduler.js';
+import { startCleanupLoop } from './tasks/cleanupTempSegments.js';
 
 const app  = express();
 const PORT = process.env.PORT || 3000;
@@ -196,4 +197,7 @@ app.listen(PORT, () => {
   // Boot the recorder scheduler tick loop after the HTTP server is live so
   // the loop's self-calls to /recorders/:id/start|stop reach a ready socket.
   startSchedulerLoop();
+
+  // Boot the temp-segment cleanup loop (runs hourly).
+  startCleanupLoop();
 });
diff --git a/services/mam-api/src/tasks/cleanupTempSegments.js b/services/mam-api/src/tasks/cleanupTempSegments.js
new file mode 100644
index 0000000..1401eb6
--- /dev/null
+++ b/services/mam-api/src/tasks/cleanupTempSegments.js
@@ -0,0 +1,41 @@
+import pool from '../db/pool.js';
+import { deleteObject } from '../s3/client.js';
+
+const CLEANUP_INTERVAL_MS = 3600_000;
+
+let _interval = null;
+
+async function cleanup() {
+  const expired = await pool.query(
+    'SELECT * FROM temp_segments WHERE expires_at < NOW()'
+  );
+
+  if (expired.rows.length === 0) return;
+
+  let deleted = 0;
+  let errors = 0;
+
+  for (const segment of expired.rows) {
+    try {
+      await deleteObject(segment.s3_key);
+      await pool.query('DELETE FROM temp_segments WHERE id = $1', [segment.id]);
+      deleted++;
+    } catch (err) {
+      console.error('[cleanup] failed to delete segment ' + segment.id + ': ' + err.message);
+      errors++;
+    }
+  }
+
+  console.log(`[cleanup] temp segments: ${deleted} deleted, ${errors} errors`);
+}
+
+export function startCleanupLoop() {
+  if (_interval) return;
+  console.log(`[cleanup] temp segments loop started (interval=${CLEANUP_INTERVAL_MS}ms)`);
+  cleanup().catch(() => {});
+  _interval = setInterval(() => cleanup().catch(() => {}), CLEANUP_INTERVAL_MS);
+}
+
+export function stopCleanupLoop() {
+  if (_interval) { clearInterval(_interval); _interval = null; }
+}