High Assurance Cryptography

We build formal verification tools and mathematically proven software to help you gain confidence in your most security-critical systems.

Customers and Supporters


Verify your Security

Cryspen offers services to perform an in-depth formal security analysis of your deployed cryptographic mechanisms, protocols, and their implementations.

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Secure Group Communication

Cryspen builds software that can help you embrace the new Messaging Layer Security (MLS) standard and integrate it securely into your technology stack.

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Post Quantum Transition

Cryspen provides services and software to upgrade the security of your systems, protocols and infrastructure with future-proof post-quantum cryptography.

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OpenMLS is an implementation of the Messaging Layer Security (MLS) protocol, a building block for implementing end-to-end encrypted applications in groups.

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Our Rust verification framework, that translates a large subset of safe Rust into the formal languages for security analysis and full functional verification.

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HACL packages are a collection of production-ready cryptographic libraries in C, Rust, OCaml, and JavaScript, developed by Cryspen on top of the HACL* project.

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hacspec is a specification language for cryptographic algorithms and protocols in Rust. An easy way for anyone to get started with formally verified cryptography.

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Libcrux is a fast, portable, formally verified cryptographic library that brings together the fastest verified artifacts from different sources.

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Hybrid Public Key Encryption (HPKE) is a new standard (IRTF RFC 9180) supporting the encryption of arbitrary-sized plaintext streams using a recipient's public key.

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