The Cryspen HACL packages is a collection of cryptographic libraries developed by Cryspen on top of HACL*. In particular, it contains a portable C crypto library that selects optimized implementations for each platform, as well as Rust, OCaml, and JavaScript bindings for this library.

Getting Started

If you want to build from sources or run tests, get started on Github.

Depending on the language you are looking for there are different entry points.


The Cryspen HACL packages are free and open source. You can find the source code on GitHub and issues and feature requests can be posted on the GitHub issue tracker. If you'd like to contribute, please read the CONTRIBUTING guide and developer section and consider opening a pull request.

The HACL* repository is a collection of high-assurance cryptographic algorithms developed as part of Project Everest. It includes source code written in F*, generated code in C, verified assembly code from the Vale project, and an agile multiplexed cryptographic provider called EverCrypt. As such, the full HACL* repository contains many software artifacts.

Get in touch for more information or support.