@yieldstar/bun-worker-invoker

Subprocess-based workflow invoker for Bun. Spawns a new child process for each workflow execution and communicates via IPC.

Install

bun add @yieldstar/bun-worker-invoker

`createWorkflowInvoker({ workerPath, logger })`

Creates a WorkflowInvoker that spawns Bun subprocesses. Each call to execute runs bun <workerPath> as a child process, sends the execution event via IPC, and waits for a response.

import { createWorkflowInvoker } from "@yieldstar/bun-worker-invoker";

const invoker = createWorkflowInvoker({
  workerPath: new URL("./worker.ts", import.meta.url).href,
  logger,
});

Param	Type	Description
`workerPath`	`string`	Path or `file://` URL to the worker script
`executable`	`boolean`	If `true`, runs the path directly instead of via `bun`
`logger`	`Logger`	Pino logger

The invoker exposes a workflowEndEmitter (EventEmitter) that fires when a workflow completes or errors. The local SDK listens on this emitter to resolve triggerAndWait promises.

When the child sends { status: "completed", response }, the emitter fires the result. When it sends { status: "error", error }, the error is deserialized with serialize-error and emitted. The child process is killed after each message.

`createWorkflowWorker(runner, logger)`

Creates a worker that listens for IPC messages in the subprocess. Call .listen() to start processing.

import { WorkflowRunner } from "@yieldstar/core";
import { createWorkflowWorker } from "@yieldstar/bun-worker-invoker";

const runner = new WorkflowRunner({ router, heapClient, schedulerClient, logger });
createWorkflowWorker(runner, logger).listen();

The worker listens on process.on("message"), converts the incoming MiddlewareEvent context into a ReadOnlyMap, and passes the event to workflowRunner.run. The result or error is sent back to the parent via process.send.