diff --git a/server/src/__tests__/workspace-runtime.test.ts b/server/src/__tests__/workspace-runtime.test.ts
index e753259544..c65f26c4d6 100644
--- a/server/src/__tests__/workspace-runtime.test.ts
+++ b/server/src/__tests__/workspace-runtime.test.ts
@@ -5884,7 +5884,12 @@ describeEmbeddedPostgres("workspace runtime service control persistence", () =>
   });
 
   afterEach(async () => {
-    await resetRuntimeServicesForTests();
+    // Terminate the real child processes this block starts and persist their
+    // stopped rows before the row deletes below. A left-over child exits later
+    // and its detached exit handler then writes a workspace_runtime_services row
+    // that references the deleted project, which raises an unhandled foreign-key
+    // error in the next test.
+    await resetRuntimeServicesForTests({ terminateProcesses: true });
     // Service control writes activity_log rows. Delete them before the company
     // delete so a lingering foreign-key row cannot block the company delete and
     // leak rows into the next test.
@@ -6923,6 +6928,12 @@ describeEmbeddedPostgres("workspace runtime startup reconciliation", () => {
   });
 
   afterEach(async () => {
+    // Startup reconciliation starts real child processes and registers them.
+    // Terminate them and persist their stopped rows before the row deletes
+    // below. A left-over child exits later and its detached exit handler then
+    // writes a workspace_runtime_services row that references the deleted
+    // project, which raises an unhandled foreign-key error in the next test.
+    await resetRuntimeServicesForTests({ terminateProcesses: true });
     // Startup reconciliation writes activity_log rows (for example, exposure
     // reservation drift). Delete those rows before the company delete. A stale
     // activity_log row holds a foreign key to the company and makes the company
diff --git a/server/src/services/workspace-runtime.ts b/server/src/services/workspace-runtime.ts
index f305aec894..261e00613c 100644
--- a/server/src/services/workspace-runtime.ts
+++ b/server/src/services/workspace-runtime.ts
@@ -6638,9 +6638,22 @@ function registerRuntimeService(db: Db | undefined, record: RuntimeServiceRecord
       runtimeServicesByReuseKey.delete(current.reuseKey);
     }
     void (async () => {
-      await cleanupRecordExposure(current);
-      await removeLocalServiceRegistryRecord(current.serviceKey);
-      await persistRuntimeServiceRecord(db, current);
+      // The child exited on its own. Record the terminal status as best effort.
+      // The persist can fail when a parent row is already gone: a caller can
+      // delete the project or the company while this service still runs, and the
+      // `project_id` foreign key then rejects the write. Catch every error here,
+      // or the detached persist becomes an unhandled rejection and crashes the
+      // host. This path runs off the child `exit` event, so no caller awaits it.
+      try {
+        await cleanupRecordExposure(current);
+        await removeLocalServiceRegistryRecord(current.serviceKey);
+        await persistRuntimeServiceRecord(db, current);
+      } catch (err) {
+        const detail = err instanceof Error ? err.message : String(err);
+        console.warn(
+          `[workspace-runtime] runtime service exit cleanup failed for ${current.id}: ${detail}`,
+        );
+      }
     })();
   });
 }