`convex dev --start` leaves `next dev --turbopack` running after `Ctrl+C`

[brandon-julio-t]

Summary

When running convex dev with --start through Bun's script runner, pressing Ctrl+C stops the Convex dev process but does not always stop the command started via --start.

In my case, the package script is:

{
  "scripts": {
    "dev": "convex dev --start 'next dev --turbopack'"
  }
}

Running bun run dev can leave the Next.js dev server running in the background after Ctrl+C, which leaves orphaned processes around and can cause memory leaks or stale dev servers on the same port.

Steps To Reproduce

1. Add a package script like:

   {
     "scripts": {
       "dev": "convex dev --start 'next dev --turbopack'"
     }
   }

2. Run:

   bun run dev

3. Wait for both Convex and Next.js to start.

4. Press Ctrl+C.

Expected Behavior

Both processes should shut down cleanly:

• convex dev should exit
• the --start command and its child processes should also exit

Actual Behavior

• convex dev exits
• next dev --turbopack can continue running in the background

Screen.Recording.2026-04-12.at.18.22.23.mp4

Impact

• orphaned dev server processes
• memory usage continues growing after Convex exits
• port conflicts on the next run
• confusing local dev behavior because Convex is stopped but Next is still alive

Environment

• OS: macOS
• Invocation: bun run dev
• Script: convex dev --start 'next dev --turbopack'
• Framework: Next.js dev server with Turbopack

Notes

• After further testing, I can only reproduce this when Convex is invoked via Bun's script runner.

• Running Convex directly, for example:

  bunx convex dev --start 'next dev --turbopack'

  shuts down correctly on Ctrl+C in my setup.

• So this appears to be specifically about the bun run invocation path rather than convex dev --start being broken in all invocation modes.

• Here are some verbose logs from the failing bun run path: https://gist.github.com/brandon-julio-t/4b276c6bd8e3fb04ce502a51297ab3b5

Maybe relevant issues:

• [BUG] SIGINT called twice npm/cli#5021
• [BUG] Improper handling of graceful exits with npx npm/cli#8164
• [BUG] Ctrl+C / SIGINT propagation to child processes broken since 10.3.0 npm/cli#7693