Windmill
Leading#2 in Open sourcehigh confidence
Fast Rust-based developer platform (~17.3k★) that turns scripts into workflows, UIs and cron jobs — for engineers who want code over drag-and-drop.Our read
Why it ranks #2
About 17.3k GitHub stars and active Discord/docs adoption support its position as a leading code-first alternative; the repository is explicitly positioned for APIs, background jobs, workflows, and internal UIs.Here is the catch
developer-centric model is not ideal for business-only users
self-hosting and worker sizing require engineering judgment
smaller connector ecosystem and review base than mainstream SaaS tools
Does this well
excellent fit for engineers who want code instead of drag-and-drop
turns scripts into reusable workflows, APIs, and UIs
fast self-hosting with strong infrastructure control
Pricing
Checked by hand on 2026-07-23. Prices in this category change often — if this looks wrong, it probably is.
Key features
scripts in Python, TypeScript, Go, Bash, SQL, and RustDAG workflows and background jobsauto-generated UIs and APIsself-hosted workers and cron schedules
Sources we read
Quick facts
More in this area
The rest of the Open source column.- 1Node-REDMature low-code, event-driven flow tool (~23.4k★, IBM origin) — the standard for wiring together devices, APIs and services, huge in IoT.
- 3Trigger.devCode-first background jobs and AI-agent workflows (~15.7k★) in TypeScript — durable, long-running tasks for developers.
- 4KestraEvent-driven, YAML-declarative orchestration and scheduling platform (~27.4k★) — broader/data-oriented, bridging workflow automation and pipeline orchestration.
- 5HKUDS/nanobotPersonal AI agent you host yourself, reachable from a bundled web UI, terminal, or chat apps like Telegram, with long-term memory and MCP tools.
- 6vercel-labs/workflow-builder-templateDeployable Next.js starter for building your own workflow tool: a React Flow canvas that compiles nodes into TypeScript run by Workflow DevKit.
- 7wassupjay/n8n-free-templatesAbout 200 importable n8n workflow files across 20-plus industries, most wired to vector databases, embeddings, and LLM calls; add credentials and activate.