n8n/packages/@n8n/scheduler

@n8n/scheduler

Durable, multi-main scheduling for n8n. Upcoming work is recorded in storage before it runs, then claimed, fired and recovered under leases and epoch fencing, so each occurrence executes once across the cluster and survives restarts and failovers. Occurrences are dispatched to handlers by taskType; the Schedule Trigger node is the first consumer. Everything sits behind N8N_SCHEDULER_ENABLED (default off) while the legacy engine stays in place.

Surface

The package is pure logic, with no DI and no database. It exposes exactly two things (plus the types their signatures reach):

• Scheduler: registerTaskHandler plus one accessor per pass (materialize, execute, reap, prune, stop). The host drives each pass on its own cadence.
• createScheduler(deps): composes the internal algorithms (materializer, executor, reaper, retention) into a Scheduler.

The host binds deps: a task store and a transaction runner (the @n8n/db repositories satisfy the store contracts structurally, so no adapters are needed), optional per-pass tuning, and an onEvent sink for described incidents. In n8n that host is the cli's DurableScheduler (packages/cli/src/scheduling/), which wires DI, config and instance identity, and routes events to the logger.

Status

Early foundation. The algorithms, schedule math and composition surface are in place; the driver that runs the passes on their cadences in the main process lands in later milestones.