Windmill Labs
Windmill

App builder

Full-code frontends connected to your backend

Build custom UIs in React or Svelte on top of your backend scripts and flows through an auto-generated, type-safe API.

React and Svelte apps on top of Windmill

The app builder lets you write a React or Svelte frontend that calls scripts and flows, also referenced as 'backend runnables'. Windmill handles execution, authentication, and hosting. You keep full control over the UI and can develop from the browser editor or locally from the CLI.

Scripts

Single functions in TypeScript, Python, Go, SQL, Bash, and 15+ other languages. Each script runs on an isolated worker.

Flows

Multi-step workflows that chain scripts into DAGs with branching, loops, retries, and approval steps.

Backend runnables

The frontend is served by the Windmill platform. When you add backend runnables to your app, Windmill auto-generates a typed wmill.ts file that makes them callable from the frontend. Your editor gets full autocomplete and type checking out of the box. Runnables execute on workers and stream results back to the UI in real time.

Read the docs
Screenshot coming soon

Datatables

Datatables are a managed layer on top of your own database that your app's backend runnables can read and write to. Windmill handles schema management and generates a DATATABLES.md context file so AI assistants understand the data model when building your frontend.

Read the docs
Screenshot coming soon

Develop from the Windmill UI or locally

Build from the browser editor or locally with the CLI, which provides scaffolding, hot reload, and AI context generation for tools like Claude Code and Cursor.

Read the docs
Screenshot coming soon
Screenshot coming soon

Deploy, version, and share

Deploy from the browser or CLI. Each deployment is versioned and can be synced to Git. Promote across staging and production workspaces.

Check our versioning dedicated page
Screenshot coming soon

Observability

Every backend runnable call is logged with its inputs, outputs, duration, and status. Run history is searchable, failed jobs show full error traces.

Check our observability dedicated page

Frequently asked questions

Build your internal platform on Windmill

Scripts, flows, apps, and infrastructure in one place.