Developer builds open-source tool after deploy bug wiped all worker process records

A developer named Giulio Ritfeld discovered a critical flaw while building a platform that runs a long-lived worker process for each user. When the manager process restarted after a deployment, its in-memory dictionary of running workers was wiped, making all active processes appear stopped. Attempting to restart workers manually created duplicate processes competing for the same resources, revealing the root cause: process state was never persisted beyond memory. The fix involved storing process records in a persistent registry and validating workers on restart using both PID and process start time to avoid false matches. Ritfeld packaged the solution into an open-source MIT-licensed library called WorkerDeck, which handles safe process lifecycle management, crash recovery with backoff logic, and manager-restart resilience.