MaxListenersExceededWarning when running many sequential child tasks via batchTriggerAndWait

[itsfabioroma]

Bug Description

When running a parent task that triggers many child tasks via batchTriggerAndWait, a MaxListenersExceededWarning appears after ~10 child tasks complete. The warning indicates SIGTERM listeners are being added to the process without cleanup.

Environment

• SDK Version: 4.1.2 (@trigger.dev/sdk, @trigger.dev/react-hooks, @trigger.dev/build)
• Node.js: v22
• OS: macOS (darwin)
• Runtime: node

Steps to Reproduce

1. Create a parent task that uses batch.triggerAndWait() to trigger multiple child tasks
2. Child tasks are simple (send HTTP request, update parent metadata via metadata.parent.increment())
3. Run the parent task with 10+ child tasks
4. Observe warning in terminal after ~10 child tasks complete

Code Structure

// Parent task
export const parentTask = task({
  id: "parent-task",
  run: async (payload) => {
    const batchItems = [/* 13 items */];
    
    const batchHandle = await batch.triggerAndWait<typeof childTask>(
      batchItems.map(item => ({
        id: "child-task",
        payload: item.payload,
        options: { concurrencyKey: item.payload.instanceNumber },
      }))
    );
    
    // Process results...
  },
});

// Child task
export const childTask = task({
  id: "child-task",
  queue: { concurrencyLimit: 1 },
  run: async (payload) => {
    // Make HTTP request
    const response = await fetch(apiEndpoint, { ... });
    
    // Update parent metadata
    metadata.parent.increment("sent", 1);
    
    return { success: true, ... };
  },
});

Warning Output

(node:54268) MaxListenersExceededWarning: Possible EventEmitter memory leak detected. 11 SIGTERM listeners added to [process]. MaxListeners is 10. Use emitter.setMaxListeners() to increase limit
(Use `node --trace-warnings ...` to show where the warning was created)

Expected Behavior

No warning should appear. SIGTERM listeners should either:

• Be reused across child task runs
• Be properly removed after each child task completes

Actual Behavior

Each child task run appears to add a new SIGTERM listener without removing it, causing the warning after 10+ runs.

Notes

• Functionality is not affected - tasks complete successfully and realtime metadata updates work correctly
• The warning appears to be from SDK internals managing graceful shutdown handlers
• Child tasks don't use any external clients (no Supabase, no DB connections) - only fetch and metadata.parent

Workaround Attempted

Tried process.setMaxListeners(50) but this just masks the issue rather than fixing the underlying listener accumulation.

[IBRAHIMFONYUY]

Hey!, i will see how i can work on that