better-effect-mq

better-effect-mq is the storage-neutral core for durable jobs, optional parent/child composition, and Layer-first Workers. A queue is a namespace, a Job is an immutable versioned producer/handler identity, and a JobStore is the atomic persistence seam. A Worker runs handlers over one existing better-effect Runtime; it does not create a second Runtime or choose a database.

For application boundaries, start with a provider-backed schema: the recommended path is Zod 4 through better-effect-schema, connected to a Job with Codec.standardSchema. This validates persisted payloads and results at the edge while keeping the core provider-neutral. The trusted JSON escape hatch is available for values that are already plain and trusted—such as a small internal payload—but is not the default for HTTP, queue or database-boundary examples.

Read the guide that matches the operation you are implementing:

• Introduction — the queue and delivery model.
• Defining Jobs — queue, identity, codecs and versions.
• Enqueueing — producer programs, admin operations and idempotency.
• Workers — handler inference and the Worker lifecycle.
• Flows — durable parent/child fan-out and result collection.
• Retries and timeouts — durable backoff and cooperative limits.
• Cancellation and shutdown — AbortSignal and graceful ownership.
• Idempotency and delivery — at-least-once processing.
• Stores and named stores — adapters and bindings.
• Testing — TestJobStore, real Workers and deterministic clocks.
• Writing a storage adapter — the advanced provider boundary.
• Operations and observability — polling, events and production checks.

Storage adapters are separate packages. The current adapter family includes PostgreSQL, Redis/Valkey, MongoDB, SQLite and MySQL; each provides the same JobStore contract and documents its migrations, client ownership and transaction boundaries in the adapter guides. The storage-neutral better-effect-mq-outbox package provides prepared outbox records, routing and a Layer-owned publisher.

The public package surface is exported from better-effect-mq; runner-neutral helpers are under better-effect-mq/testing. The package uses only better-effect and better-result as its core foundations and contains no SQL, Redis or other driver.