Cryptography Engineer

ABOUT THE ROLE

We are looking for an experienced Cryptography Engineer to join our R&D team and work on security-critical open source system where cryptography is a core part of the product.

You will be working at the intersection of applied cryptography, software engineering, security and modern distributed systems — analysing cryptographic constructions, designing secure protocols, implementing cryptographic primitives and their optimization in the framework.

This role is suitable for both cryptography-first engineers with a strong mathematical background and engineering-first developers who have substantial experience with cryptographic systems and want to go deeper into applied cryptography.
 

WHAT YOU WILL DO

• Design, implement and review cryptographic protocols and security-critical components for the framework under creation.
• Implement and integrate cryptographic algorithms and primitives into production software and its releases.
• Work with symmetric and asymmetric cryptography, digital signatures, hashing and key-exchange mechanisms.
• Design and implement secure key management and key lifecycle processes.
• Analyse existing cryptographic implementations and identify potential weaknesses.
• Participate in security and cryptographic code reviews.
• Translate cryptographic research and academic papers into practical engineering solutions.
• Develop comprehensive unit, integration, negative and interoperability tests.
• Investigate vulnerabilities, implementation flaws and potential attack vectors.
• Keep up with developments in applied cryptography, cryptographic protocols and emerging security technologies.
   

WHAT WE EXPECT

Cryptography

• Strong understanding of modern cryptographic fundamentals:
  • symmetric encryption;
  • asymmetric encryption;
  • hash functions;
  • MAC / HMAC;
  • digital signatures;
  • key exchange;
  • public-key cryptography;
  • random number generation;
  • key derivation and key management.
• Practical understanding of algorithms and constructions such as:
  • AES;
  • ChaCha20 / Poly1305;
  • SHA-2 / SHA-3;
  • RSA;
  • ECC;
  • ECDSA / EdDSA;
  • Diffie–Hellman / ECDH;
  • HKDF;
  • AEAD.
• Understanding of common cryptographic protocols and how they are used in real systems.
• Ability to reason about cryptographic security assumptions and threat models.
• Understanding of common cryptographic implementation mistakes and attack vectors.
• Ability to read and understand cryptographic papers, specifications and technical documentation.
   

Software Engineering

• 4+ years of professional software engineering experience, with significant experience working with security-critical or low-level systems.
• Strong programming skills in at least one of:
  • Rust
  • C/C++
  • Go
  • Python
• Experience designing and implementing production-grade software.
• Strong understanding of algorithms, data structures and software architecture.
• Experience with unit testing, integration testing and code review.
• Understanding of networking and modern distributed systems.
• Good understanding of operating-system concepts and how applications interact with system resources.
• Experience working with APIs, protocols and serialization formats.
   

Security

• Understanding of threat modelling and security boundaries.
• Understanding of authentication, authorization and trust models.
• Familiarity with secure software development practices.
• Ability to distinguish between a cryptographic problem and a problem that should be solved by another security control.
• Experience analysing security vulnerabilities and their potential impact.
   

WOULD BE A PLUS

• Experience with Rust and/or cryptographic libraries.
• Experience developing cryptographic libraries or security-critical components.
• Experience with TLS, PKI, X.509, certificates and key management systems.
• Knowledge of modern protocols such as HPKE.
• Experience with zero-knowledge proofs, MPC, threshold cryptography or homomorphic encryption.
• Experience with blockchain cryptography and transaction privacy.
• Knowledge of secure distributed computing.
• Experience with hardware-backed security, HSM, TPM, Secure Enclave or similar technologies.
• Experience with side-channel attacks and constant-time programming.
• Contributions to open-source cryptographic or security projects.
• Academic or professional background in cryptography, information security, mathematics or computer science.
• Publications, conference talks or research experience in cryptography/security.
   

WHAT WE OFFER

• Work on technically challenging security-critical problems.
• Opportunity to work with modern applied cryptography rather than only standard application security.
• Direct involvement in real open source system development.
• Collaboration with experienced software engineers and network engineers.
• Flexible remote / hybrid work.
• Competitive compensation.
• Paid vacation and sick leave.