Applied Cryptographer - Bitcoin DeFi

Input Output Group; Remote; GBP 60,000 - 80,000; Full time

Job summary

A leading technology company in Bristol is seeking an experienced Cryptographic Engineer to contribute to designing and implementing secure cryptographic protocols. The ideal candidate will possess a PhD in Computer Science or a related field, and have proven proficiency in Rust. This remote position offers opportunities for collaboration with distributed teams and a commitment to diversity and inclusion within the workplace.

Benefits

Remote work

Laptop reimbursement

Learning & Development opportunities

Competitive PTO

Qualifications

• PhD in Computer Science, Cryptography, Mathematics, or a related field.
• Proven experience in applied cryptographic engineering.
• Proficient in Rust with some exposure to Haskell or C.

Responsibilities

• Design and implement cryptographic constructions and libraries.
• Translate academic research into reliable production code.
• Ensure cryptographic correctness and performance.

Skills

Proficiency in Rust

Experience with Git

Knowledge of cryptographic protocols

Strong problem-solving skills

Clear communication abilities

Education

PhD in Computer Science or related field

Tools

Cryptographic libraries

Haskell

Job description

Who are we?

IOG, is a technology company focused on Blockchain research and development. We are renowned for our scientific approach to blockchain development, emphasizing peer-reviewed research and formal methods to ensure security, scalability, and sustainability. Our projects include decentralized finance (DeFi), governance, and identity management, aiming to advance the capabilities and adoption of blockchain technology globally.

We invest in the unknown, applying our curiosity and desire for positive change to everything we do. By fueling creativity, innovation, and progress within our teams, our products and services are designed for people to be fearless, to be changemakers.

What is Bitcoin DeFi:

Bitcoin DeFi is about unlocking real utility for the world's most trusted digital asset without ever compromising user control. For developers and innovators, this means finding a way to use Bitcoin in decentralized finance without forcing holders to hand their BTC to a third party. Until now, most attempts at Bitcoin DeFi have relied on "wrapped" tokens that essentially represent a promise - you send your BTC away and trust someone else to issue a proxy token on another chain. In all these custodial models, users effectively give up custody of their bitcoin to an intermediary in exchange for a tokenized representation. This status quo runs counter to Bitcoin's core ethos of self-sovereignty and security.

What the role involves:

As an experienced Cryptographic Engineer, you will contribute to the design, implementation, and integration of secure cryptographic protocols and primitives across diverse projects.

This role sits at the intersection of applied research and engineering, turning advanced cryptographic designs into robust, production-ready systems.

You will work closely with researchers, protocol designers, software architects, and QA teams to ensure cryptographic correctness, performance, and maintainability, with a strong emphasis on high-assurance coding and practical deployment.

• Collaborate with distributed teams across time zones, taking ownership of assigned tasks and delivering to agreed standards
• Design and implement cryptographic constructions, such as digital signatures, zero-knowledge proofs, verifiable random functions (VRFs), commitment schemes, and accumulators
• Develop and maintain cryptographic libraries, primarily using Rust and Haskell (with occasional use of C with attention to safety, clarity, performance, and auditability
• Translate academic research and formal specifications into reliable, well-structured production code
• Participate in cryptographic design discussions, parameter tuning, and performance benchmarking
• Analyse and validate protocol design to ensure security, via properties such as soundness, liveness, and resistance to practical attacks
• Troubleshoot, debug, and optimise cryptographic code and its interaction with broader systems
• Write and maintain clear documentation, including developer guides and internal design notes
• Stay current with developments in cryptography and assess their relevance for ongoing or future projects

Requirements

Who you are :

• Typically, a PhD in Computer Science, Cryptography, Mathematics, or a related field
• Proven experience in academic publications
• Practical experience in applied cryptographic engineering through academic research, industry work, or open-source contributions
• Proven proficiency in Rust (and ideally some Haskell) for systems-level cryptographic development
• Experience with version control systems, especially Git, in collaborative development environments
• Exposure to cryptography for blockchain, distributed systems, or consensus mechanisms is a plus
• Solid mathematical foundation in cryptography, number theory, finite fields, and probability
• Ability to work independently in highly-complex cryptographic topics
• Experience with elliptic curve cryptography, digital signatures, multi-signature schemes, and cryptographic commitments
• Familiarity with zero-knowledge proof systems and their application in distributed or blockchain-based protocols
• Hands-on experience implementing cryptographic primitives and protocols in Rust; exposure to Haskell is highly advantageous; familiarity with C is a plus
• Good understanding of cryptographic protocol design, including security properties like soundness and adversarial modelling
• Ability to read, interpret, and implement cryptographic research papers and formal specs
• Strong problem-solving and debugging skills, with a security-first mindset
• Clear written and verbal communication skills to collaborate effectively across engineering and research teams

Benefits

• Remote work
• Laptop reimbursement
• New starter package to buy hardware essentials (headphones, monitor, etc)
• Learning & Development opportunities
• Competitive PTO

At IOG, we value diversity and always treat all employees and job applicants based on merit, qualifications, competence, and talent. We do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.