Sr Applied Scientist, Cryptographic Libraries

Location: Seattle, WA, USA

Responsibilities: Develop and maintain machine-checked proofs verifying the correctness of cryptographic implementations in AWS-LC.Specify the functional behavior of low-level cryptographic code written in Rust, C, and assembly using formal notation. Verify implementations using automatic and interactive provers such as HOL-Light, Verus, and CBMC.Apply formal methods, program analysis, and rigorous testing to improve the security assurance of a widely deployed cryptographic codebase. Implement and optimize cryptographic algorithms for production use, including post-quantum algorithms such as ML-KEM, ML-DSA, and SLH-DSA.Work with senior scientists and AWS's Automated Reasoning Group on formal verification. Assist with the career development of other team members by mentoring individuals and the broader technical community. Publish patents and peer-reviewed research papers. Present research findings internally and externally; Develop formal specifications, implementations, and correctness proofs for cryptographic algorithms. Use interactive theorem provers and AI-assisted tools to develop and validate proofs end to end. Help refine algorithm implementations to improve both performance and verifiability.

Qualifications: PhD or equivalent research experience. Experience in one or more of the following areas:

• Mathematical logic
• Formal verification
• Satisfiability solving, including SAT/SMTMechanical theorem proving
• Model checking
• Program analysis

Preferred: 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, including 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, including lattice-based, code-based, or hash-based schemes.

Base salary: $167,100 to $226,100 per year for Seattle, WA.Sign-on payments and restricted stock units (RSUs) may be included in the compensation package. Comprehensive health insurance, including medical, dental, vision, and prescription coverage. Basic Life & AD&D insurance, with supplemental life insurance options; Employee Assistance Program and mental health support. Medical Advice Line and Flexible Spending Accounts. Adoption and surrogacy reimbursement coverage.401(k) matching. Paid time off. Parental leave.

Other Information: Amazon is an equal opportunity employer. Workplace accommodations are available for candidates with disabilities during the application and hiring process. The role focuses on formal verification, cryptographic implementation, algorithm optimization, and post-quantum cryptography; The position is part of Amazon Cryptographic Libraries, which maintains AWS-LC, Amazon's FIPS-validated cryptographic library. The team's cryptographic infrastructure supports AWS services and external open-source projects.