Queue worker is a background process that continuously reads jobs from a message queue and executes the associated code. It runs independently of web requests, allowing tasks such as email sending, image processing or data imports to be handled after the user sees a response.
Also called: background worker, job worker
Why it matters
Clients benefit because time‑consuming operations no longer slow down the website, leading to a smoother user experience and reduced risk of time‑out errors during peak traffic. Reliable background processing also means business‑critical jobs are less likely to be missed.
How it works
A queue system—often Redis, RabbitMQ or a database table—stores serialized job payloads. The worker is a CLI script (for example php artisan queue:work in Laravel) that polls the queue, deserialises each job, runs its handler function, then marks the job as completed or retries on failure. Workers can be supervised by a process manager such as Supervisor to keep them running continuously.
The mistake people make
A common error is to launch a worker without a process manager, so it stops after a crash or server reboot, causing jobs to accumulate and eventually time out. Another pitfall is running heavy jobs inside the request cycle instead of queuing them, which blocks the response and degrades performance.
Related terms
message queue, asynchronous processing, cron job, Laravel queue
