windmill
Open-source developer platform to power your entire infra and turn scripts into webhooks, workflows and UIs. Fastest workflow engine (13x vs Airflow). Open-source alternative to Retool and Temporal.
Star Growth
Overview
Windmill is an open-source developer platform that transforms scripts into webhooks, workflows, and user interfaces for internal tools and automation. Supporting multiple programming languages including Python, TypeScript, Go, Bash, SQL, GraphQL, PowerShell, and Rust, it serves as a self-hostable alternative to commercial platforms like Retool, Pipedream, Superblocks, and Temporal. The platform automatically generates shareable UIs from scripts, allowing developers to compose them into flows or build richer applications using low-code approaches. Windmill claims to be the fastest workflow engine, performing 13x faster than Airflow, making it suitable for high-performance automation scenarios. The platform enables organizations to build internal APIs, manage background jobs, create complex workflows, and develop custom UIs all within a unified environment. With its AGPLv3 license, teams can deploy and modify Windmill according to their needs while benefiting from commercial support options through Windmill Labs. The platform's architecture supports both Docker Compose and Kubernetes deployments, making it flexible for various infrastructure requirements.
Deep Analysis
vs Retool: open-source with code-first approach and 10+ language support; vs Temporal: built-in UI generation and low-code app builder; vs n8n: developer-oriented with real code execution rather than node-based visual programming
⚡ Capabilities
- • Script-to-UI auto-generation
- • Workflow engine with visual flow editor
- • Multi-language script execution (Python/TS/Go/Bash/SQL/Rust)
- • Low-code app builder
- • Schedule/webhook/Kafka/WebSocket triggers
- • Secret management and RBAC
- • Git sync and VS Code extension
- • Sandboxed script execution (nsjail)
🔗 Integrations
✓ Best For
- ✓ Internal tool development with auto-generated UIs
- ✓ Workflow automation replacing Retool/Pipedream
- ✓ Teams needing multi-language script orchestration
✗ Not Ideal For
- ✗ Simple cron jobs (overkill)
- ✗ Customer-facing application development
Languages
Deployment
Pricing Detail
⚠ Known Limitations
- ⚠ AGPLv3 license requires open-sourcing modifications
- ⚠ Self-hosting needs PostgreSQL and Docker
- ⚠ Learning curve for flow and app builders
- ⚠ Worker scaling requires infrastructure management
Pros
- + Multi-language support with automatic UI generation from scripts in Python, TypeScript, Go, Bash, SQL, and more
- + High performance workflow engine claiming 13x faster execution than Airflow
- + Self-hostable open-source solution with AGPLv3 license providing full control and customization
Cons
- - AGPLv3 license may restrict some commercial use cases and require careful compliance consideration
- - Being a comprehensive platform may introduce complexity for simple automation tasks
- - Self-hosting requires infrastructure management and maintenance overhead
Use Cases
- • Building internal APIs and webhooks from existing scripts without additional infrastructure
- • Creating automated workflows for background jobs and data processing pipelines
- • Developing low-code internal applications with custom UIs for non-technical team members