We’re experts in messy, real-world systems
Our founding team loves imposing order on chaos: we’ve deployed tools that retrofit safety guarantees on complex systems like Web browsers and runtimes, and we've published over 80 papers on systems security and cryptography.
Security despite
complexity
We’ve dedicated our careers to distilling (and enforcing) security properties of complex production systems. Our experience informs how we design our dev tools: we draw on our background from the lowest level—e.g., authoring the IETF hash-to-curve standard—to the highest—e.g., developing sandboxing tools for isolating untrusted code.
The technologies we’ve built transparently safeguard the data and machines of hundreds of millions of users today; the dev tools we are building will empower developers to securely ship the next generation of web3 systems.
Cubist
leadership
Riad Wahby
Co-Founder & CEO
Riad is a member of the Electrical and Computer Engineering faculty at Carnegie Mellon University. He is a leading academic researcher on zero-knowledge proofs and their applications, and is also responsible for the design and specification of several cryptographic protocols that form the basis for the security of Ethereum, Avalanche, and many other blockchains.
Riad was previously a cryptographic researcher at Algorand, and spent a decade as an analog and mixed-signal integrated circuit designer at Silicon Labs. Riad received his SB and MEng in Electrical Engineering and Computer Science from MIT, and his PhD in Computer Science at Stanford, where he was supported by a Ripple Fellowship. His work was recognized with a Distinguished Paper award at WOOT 2023.

Assistant Professor, Electrical & Computer Engineering at CMU
PhD, Computer Science at Stanford University
Ann Stefan
Co-Founder & COO
Ann is an accomplished strategy executive who spent seven years as a fintech COO in a high-risk consumer segment. For the majority of her career, she has focused on new market expansion, product development, and rapid scaling in early-stage SaaS and fintech companies. She has a rare breadth of technical and management experience spanning risk, product, sales, marketing, customer support, and government contracts.
Her core expertise centers around payment processing, online payments fraud prevention, and anti-money laundering programs, gained from years of building and running a fintech risk team and product in-house. She received a BS in Chemical-Biological Engineering from MIT and is on the Board of Directors for First Generation Alumni of MIT.

Former fintech COO
BS, Chemical-Biological Engineering at MIT
Fraser Brown
Co-Founder & CTO
Fraser is an Assistant Professor at Carnegie Mellon University’s School of Computer Science (Software and Societal Systems Department). Her research focuses on security and program correctness, from verifying (parts of) production systems to automatically finding exploitable bugs in real codebases; for example, her tools have found many zero-day bountied bugs and CVEs in the popular Chrome and Firefox browsers.
Fraser also works on compilation; in collaboration with CEO Riad and others, she developed the CirC compiler for cryptographic proof systems. Fraser received her BA in English and MS and PhD in Computer Science from Stanford, where she was supported by an NSF graduate research fellowship. Her work has been recognized with Distinguished Paper awards at IEEE Security & Privacy 2023 and WOOT 2023.

Assistant Professor, School of Computer Science at CMU
PhD, Computer Science at Stanford University
Deian Stefan
Co-Founder & Chief Scientist
Deian is an Associate Professor of Computer Science and Engineering at UC San Diego, where he co-leads the Security and Programming Systems groups. His research lies at the intersection of security and programming languages; he is particularly interested in building secure systems that are deployed in production. He was a co-founder of Intrinsic, a runtime security startup acquired by VMware in 2019.
His work has been recognized with a Most Influential Paper award (ICFP 2022), a Cybersecurity Award for Practice (IEEE 2022), Distinguished Paper awards (POPL 2019, USENIX Security 2020, ICFP 2020, POPL 2021, IEEE Security & Privacy 2023, ASPLOS 2023), an NSF CAREER award, and a Sloan Fellowship. He received his BE and ME in Electrical Engineering from Cooper Union and an MS and PhD from Stanford, where he was supported by an NDSEG graduate research fellowship.

Associate Professor, Computer Science & Engineering at UCSD
PhD, Computer Science at Stanford University
John Renner
Founding Engineer
At Cubist, John focuses on the design of developer tool interfaces. He received his PhD in Computer Science from UC San Diego, where he developed programming languages and tools to provide automated security guarantees to developers; during this time, he created CT-Wasm, a standards-track proposal to bring secure cryptography to WebAssembly.
John has also worked on internal developer tools at Google and on language-level testing support as a member of the Rust team at Mozilla.

PhD, Computer Science at UCSD
Aleksandar Milicevic
Founding Engineer
At Cubist, Aleksandar focuses on developer tools. Previously, he worked as a Principal Software Engineer at Microsoft, where he led the development of various low-level Linux-specific solutions like process sandboxing and filesystem virtualization. He was also a key contributor to a novel build system that leverages those solutions to automatically add caching and distribution to any existing build.
Aleksandar received his PhD in Computer Science from MIT in 2015. His thesis focused on designing declarative programming paradigms with the goal of building correct and robust software more easily.

PhD, Computer Science at MIT
Andres Nötzli
Founding Engineer
At Cubist, Andres focuses on compilation infrastructure. He has worked on compilers and databases, and is an expert in the design and implementation of SMT solvers; during his PhD at Stanford, Andres was one of the core developers of the cvc5 solver, an automated reasoning tool that is used extensively in industry and academia.
Prior to Stanford, Andres received his MS in Computer Science at EPFL. He has also worked on verification tools at the Amazon AWS Automated Reasoning Group, and contributed to Facebook's RocksDB, a high performance key-value store.

PhD, Computer Science at Stanford University
Our
advisors

Professor at Stanford University
Co-Director at Stanford Center for Blockchain Research

Professor at Stanford University
Co-Director at Stanford Center for Blockchain Research
Co-Founder at Stellar Development Foundation

Associate Professor at Stanford University
Co-Founder at Coverity (acquired by Synopsis)