factory
factory

Introduction

.md

What factory is, and the shape of a project that uses it.

Factory runs coding agents against your repository from workflows you write as plain async functions: await, if, try/catch, early returns. No step graph, no DSL, no YAML. It clones a fresh working tree per run, streams every event to a live web UI, and opens the pull request itself when the workflow says so.

export default defineWorkflow("fix-issue", {
  input: Schema.Struct({ issueNumber: Schema.Int }),


  run: async (ctx, input) => {
    await ctx.agent("implement", `Read issue #${input.issueNumber} with gh and implement it.`);


    // A failing test is just an `if`, not a framework concept.
    const tests = await ctx.exec(["bun", "test"]);
    if (tests.exitCode !== 0) {
      await ctx.agent("fix", `bun test is failing:\n\n${tests.stdout}`);
    }


    const pr = await ctx.writeBack({
      branch: `factory/issue-${input.issueNumber}`,
      commitMessage: `Close #${input.issueNumber}`,
      prTitle: `Fix issue #${input.issueNumber}`,
      prBody: "Opened by factory.",
    });
    return { prUrl: pr.prUrl };
  },
});

Factory is early, 0.x, and a proof of concept. It depends on effect@4.0.0-rc.* and @tanstack/ai@0.x, so expect breaking changes without a major version bump. It runs agents on your machine against your real repositories: read Before you run it before pointing it at anything you care about.

How a project is shaped

A project owns a .factory/ folder:

your-project/
└── .factory/
    ├── factory.config.ts     # repo, identity, workflow registry — committed
    └── workflows/
        └── hello.ts          # a starter workflow, yours to edit

factory.config.ts and workflows/ are committed. Everything else factory generates at runtime — the event database, the working trees — lives under .factory/ too, and init gitignores it.

Three pieces, one event log

  • Workflows — your imperative TypeScript, running against a working tree.
  • The daemon (factory serve) — owns run lifecycle, concurrency, the event database, the scheduler, and an HTTP + SSE API.
  • The UI — a browser client of that same API. Anything it does, a script can do too.

Every run appends to an append-only event log in SQLite as it happens, so a run that was interrupted still has its full history, and the UI replays then tails rather than polling for state.

Next