Windmill

Windmill turns scripts into internal tooling. You write a small script that does one job, and the platform parses its parameters, generates a form for it, and makes it callable as an API, a scheduled job or a step inside a larger flow.

The backend is Rust, running stateless API servers and workers that pull jobs from a Postgres queue, with a Svelte front end above them. Jobs are sandboxed with nsjail and PID namespace isolation, and once a job starts there is no overhead beyond roughly 50 milliseconds of queue latency.

Languages and triggers are deliberately wide.

• Runtimes: TypeScript on Bun or Deno, Python with uv, plus Go, Bash, PowerShell, PHP, Rust, C#, Java and Ansible.
• Flows and apps: chain scripts into flows, or assemble richer interfaces in the low-code app editor.
• Triggers: schedules, webhooks, HTTP routes, Kafka, WebSockets and inbound email.
• Local development: a CLI, a VS Code extension and two-way Git sync between your repository and the instance.
• Secrets: one encryption key per workspace for credentials kept in the platform's key-value store.

The Community Edition is free to use internally, while reselling it or serving it as a managed offering needs a commercial agreement. Self-hosting is three files and a Docker Compose command, or a Helm chart on Kubernetes, and it runs on AWS, GCP, Azure, Fly.io, Hetzner and others at roughly one worker per vCPU.