OSS-first docs
These docs teach the open system first: contracts, generated surfaces, runtimes, governance, and incremental adoption. Studio shows up as the operating layer on top, not as the source of truth.
Windmill
Windmill is an open-source platform that turns scripts into endpoints, workflows and UIs. It seeks to remove boilerplate by generating interfaces and workflows around existing code
Platform features
- Script-driven model. Write scripts in TypeScript, Python, Go, PHP, Bash, C#, SQL or Rust; Windmill infers dependencies, creates lockfiles and JSON schemas, then serves minimal UIs automatically
- Visual flow editor. Compose scripts into workflows with retries, error handling, loops, branching, suspending flows and approval steps
- Low-code UI builder. Build dashboards and admin panels using inline scripts and trigger flows from the UI
- Enterprise readiness. Features include RBAC permissions, secret management, OAuth handling, CLI/git sync, scheduling and webhooks
- Use cases. Deploy scripts as webhooks or cron jobs; create “applicative workflows” combining external APIs; build ETLs and interactive dashboards
- Open source & self-hosting. Windmill emphasises an open-source codebase and self-hosting options
Comparison with ContractSpec
| Feature | Windmill | ContractSpec |
|---|---|---|
| Entry model | Write scripts; platform auto-generates UI and workflows | Define typed specs (Capabilities, DataViews, Workflows, Policies); compiler outputs back-end, front-end and forms. |
| Language support | 20+ languages via embedded runtimes | Uses TypeScript/JavaScript for providers; supports other back-ends through capability providers. |
| UI generation | Minimal UI forms from script parameters; low-code app builder | Generates full web and mobile UIs from specs; user layouts can be customised via signed overlays. |
| Policy & personalization | RBAC and secret management; no per-user overlay concept | Built-in policy engine enforcing ABAC/PII on every render/mutate; overlays allow safe per-user customisation. |
| Open source | Fully open source and self-hostable | Closed-source core (SDK is open); offers hosted and on-prem modes. |
| Ideal for | Teams wanting to expose scripts as APIs, workflows or dashboards without heavy infrastructure. | Teams needing a spec-driven platform that generates code and UI, enforces policies and lets non-technical users tailor the experience. |
Windmill excels at converting scripts into workflows and admin panels. ContractSpec takes a spec-first approach, generating the entire stack and enforcing policies, making it suitable for long-lived applications that must evolve safely.
OSS docsStart with OSS. Adopt Studio when you want the operating layer.
Why ContractSpec
Keep educational and comparison content reachable without letting it define the primary OSS learning path.