Sr Applied Scientist, Amazon Cryptographic Libraries

The Amazon Cryptographic Libraries(ACL) team builds the cryptography that AWS services and a growing open-source community depend on, including AWS-LC, our FIPS-validated open-source cryptographic library. As an Applied Scientist on the team, your primary focus will be formal verification: building machine-checked proofs that cryptographic implementations are correct. You will also contribute to algorithm implementation, assembly level optimization, and the adoption of post-quantum cryptography.

You will work alongside senior scientists on the team, building deep expertise in an environment where your proofs and code ship to effectively every AWS service. This is a role where an early-career scientist gets both rigorous mentorship and immediate production-scale impact.

• Develop and maintain machine-checked proofs of correctness for cryptographic implementations in AWS-LC.
• Specify the functional behaviour of low-level cryptographic code (Rust, C, assembly) in formal notation and verify it using both automatic and interactive provers, such as HOL-Light, Verus and CBMC.
• Apply formal methods, program analysis, and rigorous testing to raise the assurance bar of a security-critical, widely deployed codebase.
• Contribute to the implementation and optimization of cryptographic algorithms, including post-quantum algorithms (ML-KEM, ML-DSA, SLH-DSA) for production use.
• Assist in the career development of others, actively mentoring individuals and the community on advanced technical issues.
• Publish patents and peer-reviewed articles and present your research both internally and externally

You take a cryptographic algorithm that needs to be provably correct and write the formal specification of its behaviour, the code and the proof of correctness. You develop the proof in an interactive theorem prover, assisted by state-of-the-art AI models and iterate until the machine checks it end to end. Some days you are debugging a proof obligation; other days you are reading a paper on a new verification technique or helping refine an algorithm implementation, so it is both fast and amenable to proof.

Your proofs back code that is validated for FIPS and deployed across AWS.

ACL owns AWS-LC (Amazon's FIPS-validated cryptographic library) and manages third-party cryptographic libraries. We build the cryptographic foundation under nearly every AWS service and a growing set of external open-source projects. Applied Scientists on the team own algorithm-level and assembly performance work and partner deeply with AWS's Automated Reasoning Group on formal verification.

• PhD or equivalent research experience, or a PhD and experience in patents or publications at top-tier peer-reviewed conferences or journals
• Experience programming in Rust, Java, C, C++, Python or related language
• Experience in any of the following areas: formal verification, interactive theorem proving, deductive verification, cryptography or mathematical logic

• Hands-on experience with automatic or interactive program verification tools, such as HOL Light, CBMC, Verus, or Lean.
• Experience specifying or verifying low-level software (machine code or assembly)
• Familiarity with cryptographic primitives and their implementation
• Low-level or systems programming experience in Rust, C or assembly
• Familiarity with post-quantum cryptography (lattice-based, code-based, or hash-based schemes)

Amazon is an equal opportunity employer and does not discriminate on the basis of protected veteran status, disability, or other legally protected status.

Our inclusive culture empowers Amazonians to deliver the best results for our customers. If you have a disability and need a workplace accommodation or adjustment during the application and hiring process, including support for the interview or onboarding process, please visit (Use the "Apply for this Job" box below). for more information. If the country/region you're applying in isn't listed, please contact your Recruiting Partner.

The base salary range for this position is listed below. Your Amazon package will include sign-on payments and restricted stock units (RSUs). Final compensation will be determined based on factors including experience, qualifications, and location. Amazon also offers comprehensive benefits including health insurance (medical, dental, vision, prescription, Basic Life & AD&D insurance and option for Supplemental life plans, EAP, Mental Health Support, Medical Advice Line, Flexible Spending Accounts, Adoption and Surrogacy Reimbursement coverage), 401(k) matching, paid time off, and parental leave.

Learn more about our benefits at .

USA, WA, Seattle -  -  USD annually