Code-first open-source developer platform (Paris + San Francisco) — founded 2022 by Ruben Fiszel (YC S22, EPFL CS graduate, ex-Palantir developer-tools lead, Stanford compilers research), 16,500+ GitHub stars on windmill-labs/windmill, $15M total funding including a $5M Series A on 8 October 2024 led by Super Angel and Dot Capital, $2.7M ARR in 2024 with an 18-person team, positioned as the open-source alternative to Retool, n8n, Temporal and Airflow
Windmill is one of the most capital-efficient and technically credible open-source developer platforms to come out of the YC ecosystem in the last three years. It sits in a unique product position: more code-first than n8n, more app-builder-capable than Temporal, more self-hostable than Retool, and dramatically cheaper than all three. The company was founded in 2022 by Ruben Fiszel, an EPFL computer-science graduate who previously led developer tools at Palantir and did compilers research at Stanford — credentials that show up clearly in the product, which is built on a Rust backend with a Svelte frontend and claims (and benchmarks publicly) 13x faster execution than Airflow. Windmill went through Y Combinator's Summer 2022 batch (YC S22), operates from a dual headquarters in Paris, France and San Francisco, and has raised approximately $15 million across two rounds — a $3M seed (Pentland Ventures, Next Play Ventures and others) followed by a $5M Series A on 8 October 2024 led by Super Angel and Dot Capital. As of 2024 disclosures the company hit $2.7 million in annual recurring revenue with an 18-person team (up from $900K ARR the prior year) — exceptional capital efficiency. The open-source repository at github.com/windmill-labs/windmill has crossed 16,500 GitHub stars. Important URL correction: the previous version of this page linked to windmill.com, which is an unrelated air-purifier brand — the correct domain is windmill.dev. For Indian buyers the right framing is: Windmill is the right call for engineering teams that want to turn Python / TypeScript / Go / Bash / SQL scripts into production workflows, internal apps and webhooks — all self-hostable on Indian cloud infrastructure. It is the wrong call for non-developers (use Zapier / Bardeen), enterprise legacy-systems RPA (use Automation Anywhere / UiPath), or teams that explicitly need Temporal-grade durable-execution guarantees on multi-week workflows.
Windmill is a code-first, open-source developer platform that lets engineers turn ordinary scripts — written in Python, TypeScript, Go, Bash, or SQL — into three production-grade artifacts at once: workflows (multi-step orchestrated pipelines), internal apps (UI surfaces over the same scripts), and webhooks / API endpoints (triggered remotely). It overlaps with several adjacent categories — Retool for internal apps, n8n for low-code automation, Temporal for workflow orchestration, Airflow for DAG-based data pipelines — but the differentiator is the code-first approach: engineers write actual code in their preferred language, and Windmill handles deployment, scheduling, scaling, secrets, permissions, UI generation, and observability.
The company was founded in 2022 by Ruben Fiszel, with backgrounds that explain Windmill's technical character. Fiszel is a computer-science graduate from EPFL (École Polytechnique Fédérale de Lausanne), one of Europe's top engineering schools, who previously led developer tools at Palantir and conducted compilers research at Stanford. The compiler / type-system pedigree is visible in Windmill's product surface: scripts are typed end-to-end (input / output schemas inferred from code), the platform generates UI form fields automatically from function signatures, and the workflow engine is implemented in Rust rather than a slower scripted runtime. Public benchmarks claim 13x faster execution than Apache Airflow — a meaningful technical advantage for high-volume data and workflow teams.
Windmill is a Y Combinator Summer 2022 batch (YC S22) company and operates a dual-headquarters structure: Paris, France (where most of the engineering team is based) and San Francisco, United States (where the YC connection and US go-to-market live). The company has raised approximately $15 million across two rounds: an initial $3M seed round with participation from Pentland Ventures and Next Play Ventures, followed by a $5M Series A on 8 October 2024 led by Super Angel and Dot Capital. The total ($8M disclosed + ~$7M of angels / SAFEs is implied by Tracxn's $15M aggregate) makes Windmill one of the more capital-efficient open-source developer platforms in the YC cohort.
By 2024 disclosures, Windmill hit $2.7M in ARR with an 18-person team — up from $900K ARR the previous year, a 3x year-over-year revenue growth on a tiny headcount. The open-source GitHub repository at github.com/windmill-labs/windmill has crossed 16,500 stars, sitting in the same star-band as n8n in its early years. For Indian buyers the relevance is direct: Windmill's open-source Community Edition is fully production-grade, MIT-licensed, and self-hostable on AWS Mumbai / Hetzner / DigitalOcean / Indian datacentres, making it an excellent fit for engineering teams at Indian SaaS / fintech / e-commerce / NBFC companies that want the capabilities of Retool / Temporal / n8n without the per-seat licensing or data-residency complications.
Write code in your preferred language. Windmill auto-generates input forms from function signatures, handles secrets / dependencies / version-pinning, and provides one-click execution. The foundation that everything else builds on.
Compose scripts into multi-step workflows with branching, parallelism, error handling, retries, approval steps, and scheduled triggers. Lighter-weight than Temporal but covers most non-mission-critical automation cases.
Drag-and-drop internal application builder over the same scripts — tables, forms, charts, buttons. Closest comparison is Retool's app builder but without the per-seat licensing or proprietary platform lock-in.
Every script can be exposed as an HTTP webhook or API endpoint, with auto-generated OpenAPI specs. Useful for triggering workflows from external systems (Stripe events, GitHub webhooks, Slack commands).
The workflow engine is implemented in Rust, with Svelte for the frontend. Public benchmarks claim 13x faster execution than Airflow for equivalent workload. The performance advantage compounds at high-volume data engineering and ETL workloads.
First-class secrets management, RBAC permissions, workspaces / folders for multi-tenancy. SAML / SCIM available on Enterprise tier. Audit logs and SSO are critical for Indian fintech / NBFC procurement.
Windmill's pricing structure changed in 2024 to a compute-units + per-seat hybrid. Live rates from windmill.dev/pricing:
The previous version of this page listed "Cloud from ₹670/mo" — that figure was loosely correct for a small Team-tier cloud account, but missed both the compute-units model and the genuine free-forever Community Edition option. For a typical 5-developer Indian SaaS team on Enterprise Cloud, the all-in monthly cost is roughly $120 + 5 × $20 = $220/month (~₹20,500 all-in with 18% IGST) — meaningfully cheaper than Retool ($10–50/user × 5+ users on top), n8n Cloud Pro, or Temporal Cloud Growth at similar workload volumes.
Windmill is the wrong call when: you have no developers on the team (use Zapier / Bardeen / n8n); you need Temporal-grade durable execution for mission-critical multi-week stateful workflows (use Temporal); you need enterprise legacy-systems RPA on mainframes / SAP / Oracle (use Automation Anywhere / UiPath); or you require a large pre-built integrations marketplace — Windmill leans toward "write the integration yourself in 5 lines of Python" rather than the 1,000-app drag-and-drop libraries that Zapier and n8n offer.