Cybersecurity Engineer, Cryptography

Client: US technology company (digital identity and payments infrastructure) · Location: remote, LATAM, US Eastern overlap · Level: senior · Engagement: full-time contractor

You will own applied cryptography across the product: key management, protocol design review and the migration plan to post-quantum algorithms.
What you will do

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Design and operate key management on HSMs and cloud KMS, including rotation, escrow and ceremonies

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Review protocol and feature designs for correct use of encryption, signatures and key exchange

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Run PKI: certificate authorities, issuance automation and mTLS between services

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Build the crypto inventory and lead the roadmap to NIST post-quantum standards (ML-KEM, ML-DSA)

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Maintain internal crypto libraries and guidance so product teams do not roll their own

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Support audits and certifications such as FIPS 140-3, PCI DSS and SOC 2

What you bring

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6+ years in security engineering, 3+ focused on applied cryptography

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Solid command of modern primitives and protocols (AES-GCM, ECC, TLS 1.3, Noise, JOSE)

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Hands-on HSM and KMS experience (Thales, AWS CloudHSM, AWS KMS or equivalent)

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Coding in Go, Rust or C, with secure coding and code review experience

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Ability to explain cryptographic risk to non-specialists in English

Nice to have

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Threshold signatures, MPC or zero-knowledge proof experience

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Degree or research background in cryptography

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Contributions to open-source crypto libraries

Originally posted on Himalayas