effect-managed-runtime

Create a ManagedRuntime once at module scope with ManagedRuntime.make(YourLayer), then call runtime.runPromise(effect) inside each handler. The runtime injects the layer's services into every effect you run.

Use runMain when Effect owns the entire process, such as CLI apps or standalone services, since it handles signals and scope automatically. Use ManagedRuntime when Effect code is embedded in a larger non-Effect system with multiple entry points.

Yes. Create the runtime at module scope so it is reused across warm invocations, and do not dispose it after every request. Dispose only when the runtime is no longer needed or the host exposes a real shutdown hook.

Memoized layers are built only once per MemoMap, so sharing one via Layer.makeMemoMapUnsafe() prevents duplicate layer construction across runtimes. With a single runtime you can omit the option and one is created automatically.

Resources acquired during layer construction, such as database pools and HTTP clients, leak because ManagedRuntime owns their scope. Wire runtime.dispose() to SIGINT/SIGTERM handlers for long-running hosts.

Avoid it when Effect owns the whole process — use NodeRuntime.runMain or BunRuntime.runMain instead — or when a long-running Effect service is the application, where Layer.launch is the right fit.