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 libcrypto. 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.

Key job responsibilities
- Develop and maintain machine-checked proofs of correctness for cryptographic implementations in AWS-LC, working alongside senior scientists. This is the core of the role.
- Specify the functional behavior of low-level cryptographic code (C, assembly) in formal notation and verify it using interactive theorem provers (HOL Light, Isabelle/HOL, or similar).
- 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 constructions (ML-KEM, ML-DSA, SLH-DSA), for production use.
- Collaborate with SDEs, security engineers, and partner teams to translate verified implementations into production-grade, FIPS-validated software.
- Grow your expertise through publications, open-source contributions, and engagement with the broader formal-methods and cryptographic research communities.

A day in the life
You take a cryptographic primitive that needs to be provably correct. Working with a senior scientist or an ARG partner, you write the formal specification of its behavior, develop the proof in an interactive theorem prover, and iterate until the machine checks it end to end. Some days you are debugging a proof obligation that does not discharge; 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, so you operate at an assurance bar most scientists never encounter this early in their career.

About the team
ACL owns AWS-LC (Amazon's FIPS-validated libcrypto), the Amazon Corretto Crypto Provider (ACCP), and managed third-party cryptographic libraries, 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 Amazon's Automated Reasoning Group on formal verification. The team has senior scientists at L6 and L7 who actively mentor and collaborate, so an early-career scientist gets both research depth and production-scale reach from day one.

Basic Qualifications

- 3+ years of building models for business application experience
- PhD, or Master's degree and 4+ years of CS, CE, ML or related field experience
- Experience in patents or publications at top-tier peer-reviewed conferences or journals
- Experience programming in Java, C++, Python or related language
- Experience in any of the following areas: algorithms and data structures, parsing, numerical optimization, data mining, parallel and distributed computing, high-performance computing
- Coursework or research experience in one or more of: formal verification, interactive theorem proving, deductive verification, program analysis, cryptography or mathematical logic

Preferred Qualifications

- Hands-on experience with an interactive theorem prover (HOL Light, Isabelle/HOL, Lean, Coq, or Verus)
- Experience specifying or verifying low-level software (machine code, C, or assembly)
- Familiarity with cryptographic primitives and their implementations
- Low-level or systems programming experience in C, Rust, or assembly
- Familiarity with post-quantum cryptography (lattice-based, code-based, or hash-based schemes)

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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 https://amazon.jobs/en/benefits.

USA, WA, Seattle - 142,800.00 - 193,200.00 USD annually