Windmill

Description

Windmill is an open-source developer platform, workflow engine, and internal-tools builder — a self-hosted alternative to Retool, Airflow, and Temporal. A script in Python, TypeScript, Go, Bash, PowerShell, or SQL becomes a webhook, a scheduled job, or a step in a multi-step flow the moment it's saved, and Windmill can auto-generate a UI form for it. Flows support branching, loops, approval steps, and retries, and a low-code app editor lets non-engineers assemble dashboards on top of the same scripts. A Rust-based distributed worker pool executes jobs in parallel, which the project benchmarks as significantly faster than comparable orchestrators like Airflow.

Features

• Scripts to endpoints: Any script instantly becomes a webhook, cron job, or flow step.
• Visual flow editor: Chain scripts across languages with branching, loops, retries, and approvals.
• App builder: Low-code drag-and-drop UIs backed directly by your scripts and flows.
• Multi-language: Python, TypeScript, Go, Bash, PowerShell, and SQL in the same flow.
• Fast execution engine: Rust-based distributed workers built for high-throughput job processing.
• Governance: Git-based version control, RBAC, audit logs, and resource/secret management.

Technology Stack

• Rust execution engine and backend
• TypeScript / Svelte frontend
• PostgreSQL for storage and job queueing
• Docker Compose or Kubernetes/Helm deployment

Requirements

• Docker and Docker Compose (or Kubernetes)
• PostgreSQL 14+
• ~2 CPU / 2 GB RAM minimum for a small instance