How it works

flowchart LR
    app["Your code<br>client.Enqueue"] -- insert --> db[("Your database<br>PostgreSQL, MySQL, SQL Server or SQLite")]
    db -- claim --> s1["kiln server<br>runs handlers"]
    db -- claim --> s2["kiln server<br>runs handlers"]
    s1 -- results, heartbeats --> db
    s2 -- results, heartbeats --> db
    dash["Dashboard"] -- reads, requeues --> db

A Client writes jobs to the store. Any number of Servers, in the same process or in others, claim the jobs of their queues, run the handler registered for each job's kind and write the outcome back. They learn about new work from the database's notifications (LISTEN/NOTIFY on PostgreSQL, an optional Redis bus on MySQL, SQL Server and SQLite) and by polling. One server at a time is also the leader: it fires recurring jobs, rescues the jobs of servers that stopped heartbeating, and prunes old jobs. There is no broker and no extra service to run.