Mistral Vibe: Background Processes Now Stop Cleanly and Can Be Disabled

Mistral VibeOct 9, 2026View original changelog

Mistral Vibe 2.26.1 changed how background processes end: stopping one now also stops everything it started in the background, and a process stays alive until all of those have exited. A new enable_background_processes = false setting stops the agent from starting them at all, and vibe -p --agent-socket sessions now run them inside the POSIX sandbox.

Key Takeaways

Stopping a background process now stops everything it spawned and waits until all of it has exited.
A background process stays alive until its whole process tree has exited, not just its shell.
enable_background_processes = false stops the agent from starting any.
vibe -p --agent-socket sessions now run background processes inside the POSIX sandbox instead of disabling them.
The change targets orphaned dev servers and watchers that outlive their parent.
It ships in Mistral Vibe 2.26.1 and complements the Vibe Code background process panel from 2.26.0.

Background Processes Are Tracked to the Last Child

Earlier behavior could leave stray work running after a background process was stopped, because only the shell was tracked. Mistral Vibe 2.26.1 changes this in two ways. Stopping a background process now also stops what it started in the background, and returns only once all of it has exited. A background process also now keeps running until everything it started has exited, not just its shell. Developers should see fewer orphaned dev servers and watchers.

A Switch to Turn Them Off

The new enable_background_processes = false setting prevents the agent from starting background processes. This is useful where long-lived processes are unwanted, such as shared machines or locked-down environments.

Sandbox in Headless Agent-Socket Sessions

vibe -p --agent-socket sessions now run background processes inside their POSIX sandbox, as enable_background_processes specifies, instead of always turning them off. Background work in these sessions therefore stays within the sandbox boundary.