Cryspen
@cryspen.com
📤 104
📥 0
📝 64
High Assurance Software
Attending the OpenSSL conference? 🗣️ Our Chief Researcher, Karthikeyan Bhargavan, is giving a talk on high assurance post-quantum cryptography. He'd love to connect, so come find him for a chat about the future of crypto!
buff.ly/JIGSr0L
#OpenSSL
#PQC
#PostQuantum
#Cryptography
#Cybersecurity
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OpenSSL Conference Prague 2025 | October 7-9, 2025
OpenSSL Conference Prague 2025 | October 7-9, 2025
https://buff.ly/JIGSr0L
1 day ago
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We're excited to see the release of Signal's new post-quantum ratcheting protocol, SPQR! We are proud to have collaborated with the Signal team on the formal analysis of the design and implementation of this. Learn more on our blog
buff.ly/Zi3rCBs
and in Signal's announcement
buff.ly/Srroli9
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Helping Secure Signal's Post-Quantum Transition
Cryspen worked with Signal to formally analyze their new post-quantum ratchet
https://buff.ly/Zi3rCBs
3 days ago
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Submissions for RWC 2026 are open now! Real World Crypto (RWC) is an annual event where cryptographers and security engineers can exchange ideas and results on the use of cryptography in mainstream applications.
buff.ly/0PoLe2D
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RWC 2026
Real World Crypto Symposium
https://rwc.iacr.org/2026/
21 days ago
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How do we prove our cryptography is secure? 🧐 Join a talk by our Chief Researcher, Karthikeyan Bhargavan, on the rise of formally verified crypto!
#cryptography
#formalverification
#cybersecurity
#PQC
#infosec
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High-Assurance Post-Quantum Cryptography OpenSSL Conference
Recent years have seen several landmark results in the formal verification of high-performance cryptographic libraries, leading to verified crypto code being adopted by mainstream projects like…
https://buff.ly/k8Z7HGP
about 2 months ago
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JZLint 2.0 is here from MTG & Cryspen to lint post-quantum certificates! Now supporting ML-KEM & ML-DSA via libcrux. Read more detail on the blog:
buff.ly/EviQFar
#PQC
#cryptography
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PQC Support for JZLint
MTG and Cryspen release JZLint 2.0: A tool for analyzing post-quantum certificates
https://buff.ly/EviQFar
about 2 months ago
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reposted by
Cryspen
European Research Council (ERC)
2 months ago
Safer web browsing now possible thanks to spinout tech rooted in academic research. 🔐 On
#WorldWideWebDay
note Karthikeyan Bhargavan & team at Inria who developed tools to improve cryptographic security online. 👉
europa.eu/!hP6t8w
#ERCPoC
#AI
#Cryptography
#Encryption
#WebSecurity
@cryspen.com
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reposted by
Cryspen
chrysn
3 months ago
We're launching the embedded-cal project: Providing access to hardware accelerated and formally proven cryptographic algorithms on
#embedded
systems in
#rustlang
. For this, I'm teaming up with @inria Paris and @cryspen, supported by the
#eu
f
unded
@NGIZero
. Right now we're going through […]
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Original post on chaos.social
https://chaos.social/@chrysn/114857907725057397
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reposted by
Cryspen
XMTP
3 months ago
As of today, XMTP is now a fully quantum-resistant decentralized messaging protocol. This means, any developer, anywhere in the world can leverage XMTP to provide their users with private, decentralized, & quantum-resistant messaging.
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We're proud to be recognized by Wavestone on their 2025 Radar of French Cybersecurity Startups. A significant milestone that validates our core mission: building the essential developer tools for creating high-assurance software. Making provably secure software accessible to all developers.
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Radar des startups cybersécurité françaises 2025
Wavestone, en partenariat avec Bpifrance, a le plaisir de publier son Radar de l’innovation cybersécurité français 2025.
https://www.wavestone.com/fr/insight/radar-des-startups-cybersecurite-francaises-2025/
3 months ago
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Cloudflare has launched Orange Me2eets, an open-source end-to-end encrypted video calling demo! Built on top of our OpenMLS implementation, this project showcases secure, private real-time communication.
buff.ly/eEdJdnf
#Cloudflare
#E2EE
#VideoCalling
#OpenSource
#OpenMLS
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Orange Me2eets: We made an end-to-end encrypted video calling app and it was easy
Orange Meets, our open-source video calling web application, now supports end-to-end encryption using the MLS protocol with continuous group key agreement
https://blog.cloudflare.com/orange-me2eets-we-made-an-end-to-end-encrypted-video-calling-app-and-it-was/
3 months ago
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Cryspen is excited to announce it has been awarded a grant from the Ethereum Foundation to extend our hax verification toolchain with support for the Lean prover. Watch this space for more on this soon!
#FormalVerification
#Lean
#Rust
4 months ago
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At IEEE S&P, Théophile Wallez presented new results on the formal security verification of a bit-precise executable specification of TreeKEM, the core key agreement component of the MLS protocol. This work was done in collaboration with chief research scientist Karthikeyan Bhargavan.
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TreeKEM: A Modular Machine-Checked Symbolic Security Analysis of Group Key Agreement in Messaging Layer Security
The Messaging Layer Security (MLS) protocol standard proposes a novel tree-based protocol that enables efficient end-to-end encrypted messaging over large groups with thousands of members. Its…
https://buff.ly/UZCmJyR
4 months ago
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Thrilled to welcome Clément to Cryspen's Tools and Proofs team! 🎉 His expertise in formal methods (PhD from Inria Paris!) will be for conducting rigorous proofs and enhancing our tooling. Welcome, Clément! 🚀
#NewHire
#FormalMethods
buff.ly/Ab4wuNA
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Cryspen Welcomes Clement
A Warm Welcome to Clement, Our Newest Cryspen Crew Member!
https://cryspen.com/post/welcome_clement/
5 months ago
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Updates from some of Cryspen's Open Source Projects! Check out our latest updates: - Dive into the latest developments from the past month on 𝐡𝐚𝐱.
buff.ly/trIZnTx
- And see how the 𝐎𝐩𝐞𝐧𝐌𝐋𝐒 project is progressing and what's on the horizon.
buff.ly/LAxrwnH
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This Month in Hax: April 2025 - hax
In April, we successfully merged 38 pull requests!
https://hax.cryspen.com/blog/2025/05/05/this-month-in-hax-april-2025/
5 months ago
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MLS Group State Forks: What, Why, How Group state forks are faulty states that MLS groups can end up in. We have a new blog post that looks at what they are exactly, how that happens and how to resolve them, and how a a new OpenMLS feature makes fork resolutions a little easier.
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MLS Group State Forks: What, Why, How
What are state forks, why can’t they happen but do anyway and how can they be resolved in OpenMLS?
https://buff.ly/Tu5xNm1
6 months ago
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Rust identifiers, demystified! We're revealing our analysis toolchain's secrets in our latest blog. Discover how we tackle global vs. local identifiers for better formal verification with hax. Read the full story:
buff.ly/fWGDzLY
#RustLang
#CodeAnalysis
#HighAssurance
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Redesigning Global Identifiers in hax - hax
A careful treatment of identifiers lies at the heart of all code analysis frameworks, and we hope our experience here proves useful to others.
https://buff.ly/fWGDzLY
6 months ago
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Updates from some of Cryspen's Open Source Projects! Check out our latest updates: - Dive into the latest developments from the past month on 𝐡𝐚𝐱.
buff.ly/TJpxWW1
- And see how the 𝐎𝐩𝐞𝐧𝐌𝐋𝐒 project is progressing and what's on the horizon.
buff.ly/VAJxltR
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This Month in Hax: March 2025 - hax
In March, we successfully merged 32 pull requests!
https://buff.ly/TJpxWW1
6 months ago
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RWC 2025 buzzed with energy as the cutting edge of cryptography was presented to and discussed among an audience. Today, Cryspen teamed up with Google to showcase practical, scalable, verified solutions for high-assurance software and post-quantum cryptography.
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Cryspen @ RWC 2025
Real World Crypto 2025 buzzed with energy as the cutting edge of cryptography was presented to and discussed among an audience of leading researchers and developers from academia and industry. Today,…
https://buff.ly/qc3lpn2
7 months ago
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New blog post! 📝 Control flow analysis with Hax. In this post we show how to ensure control flow properties such as "function A is always called before function B" in Rust. Super relevant for security! 🔒
buff.ly/ntTW299
#rustlang
#formalverification
#security
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Control flow analysis with hax
A difficulty of formal verification is that specifying programs can be hard. Certain kinds of programs can end up having a specification that is as complex as the code itself. In this case it is…
https://buff.ly/ntTW299
7 months ago
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reposted by
Cryspen
Real World Crypto Symposium
8 months ago
Thank you to new sponsors of Real World Crypto 2025, CASA, Chelpis Quantum, Cryspen, and Interop Labs! Your contributions are essential in making this conference possible and we look forward to seeing you in Sofia!
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Cryspen is heading to RWC in Sofia next week! 🚀 We'll be presenting "Using Formally Verified Post-Quantum Algorithms at Scale" and our team will be on hand to discuss all things high assurance software and crypto. Oh, and we're sponsoring too!
buff.ly/IC7eg8O
#RWC
#Cryptography
#PostQuantum
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RWC 2025
Real World Crypto Symposium
https://buff.ly/IC7eg8O
7 months ago
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Exciting to see MLS gaining traction! 🚀 This increased adoption is a huge win for security and privacy in messaging.
#MLS
#Security
#Privacy
#XMTP
#OpenMLS
add a skeleton here at some point
7 months ago
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New Blog Post: Making hax More Usable for Everyone! We've just published a new technical blog post detailing our ongoing efforts to improve hax. Learn about the strategies and implementations we're employing to make hax more usable and efficient for all users.
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Hax for everyone - hax
The hax toolchain has been successfully used to formally verify our cryptographic implementations for ML-KEM,Bertie and more. All these projects are developed with formal verification (using hax) in…
https://buff.ly/DhrcxML
7 months ago
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We welcomed Clara to the Cryspen team this month! She's a TU Berlin grad, a Rust enthusiast, and a passionate open-source contributor. Her skills in low-level programming and commitment to secure software make her a perfect fit for our mission.
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Cryspen Welcomes Clara
A Warm Welcome to Clara, Our Newest Cryspen Crew Member!
https://buff.ly/4gyGEwc
8 months ago
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We are excited to be part of the PROTECT team to develop new approaches to make IT systems more resilient.
www.dfki.de/en/web/news/...
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Protecting against cyberattacks: Project sets new standards in IT security with formal verification and flexibility
Cyberattacks on companies and public institutions are increasing dramatically worldwide. The PROTECT project, funded by the Cyberagentur, is developing solutions to enhance the resilience of IT system...
https://www.dfki.de/en/web/news/projektstart-protect
8 months ago
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Our paper "hax: Verifying Security-Critical Rust Software using Multiple Provers" is now available on eprint and will be published in the VSTTE 2024 proceedings.
add a skeleton here at some point
8 months ago
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🚀 hax is entering a new era! 🚀 We're excited to announce the launch of our new website and our first official release! Check out our latest blog post to learn more about this exciting new chapter 🔗
https://hax.cryspen.com/blog/2025/01/21/a-new-chapter.html
#opensource
#hax
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A new chapter - hax
We're thrilled to announce that hax is entering a new era of stability and growth with the launch of our new website, a fresh start at Cryspen, and our first official release, v0.1.0!
https://hax.cryspen.com/blog/2025/01/21/a-new-chapter.html
9 months ago
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Cryspen is thrilled to be part of the "Verifiably Secure IT Ecosystem" funded by the Cyberagentur! 🚀
add a skeleton here at some point
9 months ago
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Test your PQC readiness now! Our new website, featuring our formally verified libcrux crypto library, makes it easy to see if your browser is future-proof. Head over to
https://buff.ly/4ak1LB6
to test your browser and learn more about post-quantum cryptography.
#postquantumcrypto
#cryptography
9 months ago
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Cryspen is looking for a talented Proof Engineer to join our team in Germany or France! 🇫🇷🇩🇪 Cryspen is on a mission to build high-assurance software and formal verification tools that make the world a safer place.
https://buff.ly/4jeEJiN
#ProofEngineering
#Hiring
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Jobs
Work with us
https://buff.ly/4jeEJiN
9 months ago
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Great News! Cryspen's libcrux crypto library was mentioned in a recent article in The Register. If you're interested in learning more about how libcrux can be used to improve the security of your applications, please visit our website or contact us.
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Boffins carve up C so code can be converted to Rust
Mini-C is a subset of C that can be automatically turned to Rust without much fuss
https://buff.ly/3W3FYaK
9 months ago
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bertie.cryspen.com
now available with mlkem TLS and Bertie We've launched
bertie.cryspen.com
with mlkem TLS, powered by our Bertie TLS 1.3 implementation. This provides a secure and efficient endpoint for your applications. Read more here:
https://buff.ly/3ZOiJT3
#mlkem
#TLS
#pqc
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X25519MLKEM768 TLS-Handshake in Bertie
https://bertie.cryspen.com
10 months ago
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Updates from Cryspen's Open Source Projects! Check out our latest updates: - Dive into the latest developments from the past month on 𝐡𝐚𝐱.
buff.ly/3VgVccc
- And see how the 𝐎𝐩𝐞𝐧𝐌𝐋𝐒 project is progressing and what's on the horizon.
buff.ly/4fVzNgX
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This month in hax: November 2024
Despite some team members attending an offsite work week event, we merged 24 PRs this month. Here’s an overview of the work of the month. The frontend remained stable this month, with only a few pull ...
https://buff.ly/3VgVccc
10 months ago
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reposted by
Cryspen
Berlin Crypto Meetup
11 months ago
📣 Upcoming Event! Our next Berlin Crypto Meetup is coming up! We've got two great talks lined up. Be part of the growing Berlin crypto community. 📆 December 4 🕖 From 19:00 to 22:00 📍 Secure Systems Engineering GmbH Hauptstraße 3 10827 Berlin
www.eventbrite.de/e/berlin-cry...
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Berlin Crypto December 2024
Where the Berlin Crypto Community gets together.
https://www.eventbrite.de/e/berlin-crypto-december-2024-tickets-1036773045087
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Cryspen is looking for a talented Rust Software Engineer to join our team! 🇫🇷🇩🇪
join.com/companies/cr...
We encourage applications from all qualified candidates, regardless of their background or identity.
#Hiring
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Jobs at Cryspen | JOIN
Jobs at Cryspen. Browse all our open positions and become part of our growing team! We are currently looking for additions to our company. Apply today!
https://join.com/companies/cryspen
11 months ago
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At VSTTE 2024 in Prague, Karthik spoke about how formal verification can be used to speed up the development and clarify the security of real-world cryptography from design to implementation. Slides are up! Check them out.
cryspen.com/post/vstte20...
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Cryspen @ VSTTE 2024
Karthik gave an invited talk on High Assurance Post-Quantum Cryptography at VSTTE 2024.
https://cryspen.com/post/vstte2024/
12 months ago
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Our Chief Researcher, Karthik, is giving an invited talk today at VSTT in Prague! He will delve into the fascinating world of modern cryptography and software verification and discuss how formal verification is being used to improve the security of real-world systems.
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VSTTE 2024
October 14-15, 2024, Prague, Czech Republic Co-located with Formal Methods in Computer-Aided Design 2024 (FMCAD 2024)
https://buff.ly/3Nna8km
12 months ago
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Updates from Cryspen's Open Source Projects! Check out our latest updates: - Dive into the latest developments from the past month on hax.
buff.ly/3XS4ifI
- And see how the OpenMLS project is progressing and what's on the horizon.
buff.ly/4gJVxgp
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This month in hax: September 2024
In July, we merged 33 PRs! 🎉 On the side of the frontend, Nadrieril and I worked at making hax handling of binders (e.g. 'a in for<'a> &'a T: PartialEq<i32>) and traits better. This is not finished ye...
https://buff.ly/3XS4ifI
about 1 year ago
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When implementing cryptographic protocols, ensuring input validation is paramount. Neglecting this can lead to severe vulnerabilities. In a recent blog post, Jan delved into how we address input validation in OpenMLS, an open-source Rust implementation of the MLS protocol.
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Taking Stock of Validation Checks
When implementing cryptographic protocols, probably the most important thing is to not forget validating all inputs. Failing to do so can lead to inadvertant leakage of private information, state…
https://buff.ly/47P9vJL
about 1 year ago
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Our Chief Researcher Karthik Bhargavan has been invited to present at the 6-th Future-IoT School this week. His talk is titled "Formal Guarantees for Secure IoT Systems" and will dive into how formal methods can help building secure IoT systems.
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6th Future-IoT PhD School – IoT meets Secure Supply Chain, 30.9.-4.10.2024 in Paris, France
IoT meets Secure Supply Chain, 30.9.-4.10.2024 in Paris, France
https://buff.ly/3XMNred
about 1 year ago
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Real World Crypto (RWC) 2025 is now open for submissions! 🌍 As part of the program committee, we're excited to see the latest groundbreaking research and practical applications in applied cryptography.
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RWC 2025 paper submission
Real World Crypto Symposium
https://buff.ly/4d3bhYZ
about 1 year ago
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We are happy to announce the release of OpenMLS v0.6, a significant update to our open-source MLS implementation. This version includes several new features and improvements. Read all details on the blog:
https://buff.ly/47aL5dz
#MLS
#opensource
#cryptography
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OpenMLS 0.6 released
Today, we are releasing version 0.6 of OpenMLS. In this post we’ll go over the most significant changes since our last release. New Storage Provider To make it easier to persist group state, the…
https://buff.ly/47aL5dz
about 1 year ago
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Our Chief Researcher, Karthikeyan Bhargavan, delivered a captivating talk at Crypto 2024. His presentation, titled "Integrating Formal Verification in Cryptographic Standards and Implementations", is now available on YouTube.
www.youtube.com/watch?v=PIma...
#crypto
#formalverification
add a skeleton here at some point
about 1 year ago
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Our Chief Research Scientist, Karthikeyan Bhargavan, was invited to speak at Crypto, the world's leading cryptography conference. He shared insights on using formal methods to enhance the security of protocols like PQXDH, TLS, and MLS.
cryspen.com/post/crypto2...
#cryptography
#formalmethods
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Cryspen @ Crypto 2024
Karthik gave an invited talk on Formal Methods for Cryptography at Crypto 2024.
https://cryspen.com/post/crypto2024/
about 1 year ago
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Thrilled to share that we've teamed up with Google to create formally verified implementations of NIST's post-quantum algorithms. These open-source solutions will offer robust security guarantees, high performance, and are designed for widespread adoption.
bughunters.google.com/blog/6038863...
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Blog: Formally Verified Post-Quantum Algorithms
In our latest post on PQC, we discuss how we are partnering with Cryspen to produce formally verified implementations of the NIST-selected post-quantum algorithms.
https://bughunters.google.com/blog/6038863069184000/formally-verified-post-quantum-algorithms
about 1 year ago
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We’re proud to announce the hax playground! Inspired by the Rust Playground, the hax playground allows you to play with hax directly in your web browser! This provides a first glimpse at Cryspen’s upcoming verification workbench!
hax-playground.cryspen.com
More details:
cryspen.com/post/announc...
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Announcing the hax Playground
Our Rust verification framework now has a web playground!
https://cryspen.com/post/announcement-playground/
about 1 year ago
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This month in hax #2
hacspec.org/blog/posts/t...
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This month in hax: July 2024
In July, we merged 32 PRs! 🎉 On the side of the frontend and CLI, we had a lot of fixes and improvements! The hax command line and rustc driver were refactored, allowing for better scaling and caching...
https://hacspec.org/blog/posts/this-month-in-hax/2024-07/
about 1 year ago
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We’re thrilled to announce that Maxime Buyse has joined Cryspen as a Formal Verification Engineer! Maxime is a whiz when it comes to formal methods, software verification, and compilers. His expertise will be instrumental in supercharging our tools.
cryspen.com/post/welcome...
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Cryspen Welcomes Maxime
Maxime joins the Cryspen family.
https://cryspen.com/post/welcome_maxime/
about 1 year ago
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Last week, at the National CyberSecurity Center of Excellence in Maryland, NIST hosted a workshop on Formal Methods within Certification Programs.
cryspen.com/post/fmcp/
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Cryspen @ FMCP 2024
We gave a talk at the NIST workshop on Formal Methods within Certification Programs.
https://cryspen.com/post/fmcp/
about 1 year ago
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We are excited to collaborate with SandboxAQ on formally verified software. This collaboration marks a significant step towards making our hax toolchain accessible to a wider audience, transforming it into a tool for software architects, engineers, and crypto experts.
cryspen.com/post/hax-san...
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Unlocking New Possibilities
Cryspen partners with SandboxAQ to accelerate hax adoption
https://cryspen.com/post/hax-sandbox/
about 1 year ago
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