Welcome Xavier Bruni

We’re excited to welcome Xavier Bruni to Dfns as Staff Security Engineer. Security has always been core to how we build Dfns, not as a feature, but as a discipline embedded into every layer of the platform. Xavier brings deep, hands-on security experience from some of the most demanding environments in crypto and fintech, further strengthening our security foundations.

Deep security experience from exchanges to infrastructure

Xavier has spent his career building and running security for production systems. Most recently, he led application security at Deribit, the world’s largest crypto options exchange, and continued in that role after its acquisition by Coinbase. He built and operated security programs at scale, including SAST and DAST pipelines, supply-chain security, DevSecOps practices, penetration testing and audits, bug bounty programs, incident response, and compliance with standards such as ISO 27001, SOC 2, and CCSS.

Before that, Xavier was CTO at Lyber, where he led engineering and system architecture while achieving and maintaining regulatory compliance. He also co-founded a cybersecurity firm, OPCODES, focused on smart contract audits across EVM and Solana. Earlier in his career, he worked on deep technical security at Thales and got a degree in computer science from a top engineering school, Centrale Lille.

Engineering end-to-end zero trust into the platform 

At Dfns, Xavier will work across the stack to continuously raise our security bar. That includes strengthening application security, hardening our SSDLC, improving detection and response, driving audits and certifications, building security features into the platform (e.g., transaction scanning, simulation, behavioral analytics) and helping ensure that security scales alongside our product and customer base.

Security is not optional for us. We build wallet infrastructure and orchestration systems that sit at the core of financial institutions and fintech platforms. Our clients rely on us to protect assets, enforce policies, and provide cryptographic guarantees under all conditions. That means security must be proactive, measurable, and engineered into how we ship software every day. Xavier’s background, spanning exchanges, custody-grade systems, audits, and compliance, fits exactly with that philosophy. We’re thrilled to have him on board and excited about the impact he’ll have as we keep pushing Dfns forward.

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