My guess would be that their app isn’t running with PID 1. This can happen when services are launched from an entrypoint script in docker without using exec. If

My guess would be that their app isn’t running with PID 1. This can happen when services are launched from an entrypoint script in docker without using exec. If the request is fulfilled and the system sends a sigint to the container, docker will relay that to whatever is running on pid 1. If that’s their app, it’ll flush logs and quit. If their app is using another pid, docker will kill the container by force.