Windmill
Open-source developer platform and workflow engine
Founded
2022
Starting Price
0
Category
Developer Tools
Last updated April 27, 2026
About Windmill
Windmill is an open-source platform to build, deploy, and monitor internal tools from scripts. It turns scripts into auto-generated UIs, APIs, cron jobs, and workflows with sub-20ms overhead, supporting Python, TypeScript, Go, Bash, SQL, and more. It positions itself as an alternative to Retool, n8n, Airflow, and Temporal.
Pros & Cons
Pros
- Fastest open-source workflow engine with sub-20ms overhead per step
- True open source (AGPLv3) and fully self-hostable avoiding vendor lock-in
- Multi-language flexibility supporting 9+ languages natively plus Docker images
- Code-first with low-code option balancing developer control with accessibility
- Generous free tier with unlimited executions and up to 50 users
Key Features
Multi-Language Script Editor
Write and execute scripts in Python, TypeScript, Go, PHP, Bash, SQL, Rust, or any Docker image with full LSP support
Workflow Orchestration
Build DAG-based workflows with conditional branches, parallel execution, for-loops, and sub-20ms per-step overhead
Low-Code App Builder
Drag-and-drop editor to create data dashboards and internal apps combining visual components with code
Auto-Generated UIs
Automatically generates user interfaces for scripts and flows based on their parameters
Scheduling & Triggers
Run scripts on schedules, via webhooks, CLI, Slack commands, or email triggers with full monitoring
Self-Hosting & Open Source
Fully open-source (AGPLv3) and self-hostable with complete control over data and infrastructure
Enterprise Security
Granular RBAC, SSO/SAML, secret management, OAuth, audit logs, and SOC 2 compliance
Pricing
Free / Community
0
- Unlimited executions
- Up to 50 users
- 3 workspaces
- Community Discord support
Pro
120/month
Best For
Internal Tool Development
Rapidly build admin panels and operational tools by turning backend scripts into applications with auto-generated UIs
Data Pipeline Orchestration
Orchestrate ETL/ELT workflows across databases, APIs, and file storage with DAG-based flows
IT & DevOps Automation
Automate infrastructure tasks, CI/CD pipelines, monitoring alerts, and incident response workflows
Business Process Automation
Build approval flows, notification systems, and cross-service integrations with human-in-the-loop steps
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