Pranay Prakash
08318f6da0
Review follow-ups on #4100: - The queue-owned row no longer sends a backstop per running step per replay. The dispatch pass folds every queue-owned running step into ONE delayed run continuation, due when the latest bare start's lease expires and keyed `${runId}:queue-backstop:${latestStartedAt}`. The invocation remembers the epochs it armed and skips the send on later passes over an unchanged log, so three replay passes over one running step (or one pass over N running steps) cost a single publish; concurrent invocations collapse onto one pending wake server-side via the shared key. A coarser bucket key would either be deduped against an in-flight wake that fires before a newer step's lease expires, or need a delay past the queue's per-message cap, so the epoch is the key. A wake on a finished run is the ordinary already-terminal exit. - `isQueueOwnedRunning` additionally requires the run's specVersion to be at or above SPEC_VERSION_SUPPORTS_SLOT_IDENTITY (6), the first spec version every ownership-stamping runtime mints (#2848 shipped under spec 5). A bare start on an older or unknown run is not proof of a queue delivery, since the replay contract tolerates a legacy unstamped inline start, so such runs keep the immediate re-enqueue. - `workflow.queue_ownership.backstop_wakes_armed` is now 0/1 per pass. Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Workflow SDK
Workflow SDK makes TypeScript and JavaScript functions durable. It persists workflow progress, retries failed steps, and provides built-in observability. Workflows can suspend without using compute while they wait.
Quick start
Install the SDK in an existing project:
npm install workflow
Configure the integration for your framework. For example, with Next.js:
// next.config.ts
import { withWorkflow } from 'workflow/next';
export default withWorkflow({});
Then start a workflow from an API route, Server Action, or other server-side code:
import { start } from 'workflow/api';
import { onboardUser } from './workflows/onboard-user';
await start(onboardUser, ['hello@example.com']);
Run your app, then open the local observability UI in another terminal:
npm run dev
npx workflow web
Choose your framework in the getting-started guides.
Note
The
workflowpackage includes its full documentation, so coding agents can read version-matched guides locally fromnode_modules/workflow/docs.
Run anywhere
Local development uses the bundled backend with no configuration. Deploy to Vercel for managed storage, queuing, scaling, and observability. To self-host, use the Postgres backend or implement a custom World.
The Worlds page lists maintainer-curated third-party Worlds, including self-hosted and managed options. Submit your World by updating the Worlds Manifest.
Community
The Workflow SDK community lives on GitHub Discussions, where you can ask questions, share ideas, and show what you have built.
Contributing
Contributions are welcome. Use issues and discussions to collaborate with the team and wider community. By participating, you agree to our Code of Conduct.
Security
If you find a security vulnerability in Workflow SDK, disclose it responsibly instead of opening a public issue.
To participate in our Open Source Software Bug Bounty program, please email responsible.disclosure@vercel.com. We will add you to the program and provide further instructions for submitting your report.