On the recordRead 11 Oct 202613 facts
F*
Plans and prices
F*
Free
Apache 2.0 licensed · binaries for Windows, Linux, and Mac OS X · install via OPAM, Docker, or Nix, or build from source
Read 11 Oct 2026 · fstar-lang.org
On the record
- Community support
- The project directs questions to GitHub Discussions and a public Zulip forum, and lists a low-traffic mailing list and maintainer contact email.fstar-lang.org · read 11 Oct 2026
- Compilation
- F* programs compile by default to OCaml, and fragments can also be extracted to F#, C, WebAssembly, or assembly using KaRaMeL or Vale.fstar-lang.org · read 11 Oct 2026
- Core team
- The listed core development team includes contributors affiliated with Microsoft Research in Redmond and Bangalore.fstar-lang.org · read 11 Oct 2026
- Development
- F* is open source on GitHub and is under active development by Microsoft Research, Inria, and the community.fstar-lang.org · read 11 Oct 2026
- Implementation
- F* is implemented in F* and bootstrapped using OCaml.fstar-lang.org · read 11 Oct 2026
- Installation
- The project offers binaries for Windows, Linux, and Mac OS X, and installation through OPAM, Docker, Nix, or source builds.fstar-lang.org · read 11 Oct 2026
- Learning
- The site links to an online book, browser examples and exercises, and a tutorial for Low*, a low-level subset that can compile to C through KaRaMeL.fstar-lang.org · read 11 Oct 2026
- License
- F* is distributed under the Apache 2.0 license.fstar-lang.org · read 11 Oct 2026
- Parser tooling
- EverParse generates C code from formally proven F* and is used in production, including in Windows Hyper-V.fstar-lang.org · read 11 Oct 2026
- Production use
- The site says code from HACL*, ValeCrypt, and EverCrypt is used in production projects including Firefox, the Linux kernel, Python, mbedTLS, and WireGuard.fstar-lang.org · read 11 Oct 2026
- Proof system
- It combines dependent types with proof automation based on SMT solving and tactic-based interactive theorem proving.fstar-lang.org · read 11 Oct 2026
- Purpose
- F* is a general-purpose proof-oriented programming language for purely functional and effectful programming.fstar-lang.org · read 11 Oct 2026
- Security use
- Project Everest develops high-assurance secure communication software in F*, and HACL* provides high-assurance cryptographic primitives written in F* and extracted to C.fstar-lang.org · read 11 Oct 2026
