Resonate on Postgres

Dead simple durable execution.

Resonate durable execution runs your code as a reliable workflow, checkpointing each step as a durable promise, sleeping for days, surviving crashes and restarts. resonate-pg is one SQL file. No additional servers, queues, or timers — Postgres, with pg_cron, is all three. Full Resonate docs live at docs.resonatehq.io.

resonate.register(
  "countdown",
  async function countdown(ctx: Context, n: number) {
    for (let i = n; i > 0; i--) {
      await ctx.run(() => console.log(`countdown: ${i}`));
      await ctx.sleep(10 * 60 * 1000); // durable: no process waits
    }
    await ctx.run(() => console.log("liftoff 🚀"));
  },
);

Crash the process, redeploy, or lose the machine mid-run — the workflow resumes on the right number, and nothing runs twice. Each ctx.run is checkpointed to Postgres as it completes, so a resumed run replays finished steps from the database instead of re-executing them. And ctx.sleep is just a row with a deadline: the invocation returns and nothing runs until it fires, whether that's ten minutes or ten days from now.

On Supabase? example/countdown goes from an empty project to a running durable workflow in about five minutes.

Getting started

resonate-pg is a Resonate Server in a single file running on Postgres 16+:

psql -d yourdb -f resonate.sql

Extensions

• pg_cron (required — drives all timers)
• pg_net or pgsql_http (optional — either one enables HTTP push delivery)

SDK

You write workflows with a Resonate SDK:

• TypeScript
• Python
• Go
• Java
• Rust

Operations

Completed workflows stay in the database. Delete old ones on a schedule:

-- daily at 03:00: delete workflows finished more than 7 days ago
select cron.schedule('resonate-gc', '0 3 * * *',
  $$select resonate.gc((extract(epoch from now())*1000 - 7*86400000)::bigint)$$);

Keep the horizon longer than any window in which you might re-send the same workflow id; ids are idempotent only while the row exists.

Under the hood

resonate-pg is a faithful implementation of the Resonate protocol: every protocol action is a stored procedure, callable via resonate_rpc:

SELECT resonate.resonate_rpc('{"kind":"promise.get","head":{},"data":{"id":"invoke:foo"}}');

Community

Questions, ideas, or want to help? Join the Resonate Discord, or open an issue or pull request — contributions welcome. resonate-pg is part of Resonate.

License

Apache 2.0.