Senior Software Engineer

About the role: As a Senior Software Engineer at Common Prefix you will design, implement, and maintain blockchain software solutions. You will work on end‑to‑end implementation of protocols, collaborate with scientists, auditors, and product teams, and help drive the technical vision of the company.

Responsibilities

• End‑to‑end implementation of blockchain software.
• Develop code in a variety of programming languages including Rust, Go, JavaScript, TypeScript, Solidity, and Python.
• Write unit, end‑to‑end, and integration tests to ensure reliability of financial systems.
• Identify and fix bugs and security issues in your own and others’ code.
• Conduct code reviews for colleagues within and outside the team.
• Work with auditors to ensure correctness of mission‑critical software.
• Manage software lifecycle and DevOps processes.
• Design and prototype software to demonstrate to clients in early phases.
• Turn prototypes into production‑grade software and manage deployment to testnets and mainnets.
• Ensure system stability and safety while handling millions of dollars in total value locked.
• Build monitoring tools, diversify infrastructure, and eliminate single points of failure.
• Communicate scientific and security requirements with the research team.
• Attend lectures, courses, or read academic papers to stay up‑to‑date.
• Teach engineering details back to the scientific team.
• Communicate with project stakeholders to align on business requirements.
• Represent the company in client calls when needed, supported by business and science teams.
• Write blogs and tweets in collaboration with the marketing team.
• Mentor engineers and optionally take ownership of projects.
• Develop internal tools and open‑source software for the blockchain community.

Requirements

• 5+ years of software engineering experience.
• Experience designing large‑scale software spanning hundreds of thousands of lines of code.
• Experience in network programming (sockets, APIs).
• Proven track record in blockchain technology (e.g., Solidity smart contracts on Ethereum, CosmWasm on Cosmos, Bitcoin scripts) is a plus.
• Familiarity with blockchain ecosystems, Layer 2 solutions, rollups, light clients, bridges, and DeFi is a plus.
• Degree in Computer Science (BSc, MSc/MEng, or PhD) is a plus.
• Understanding of cryptography theory and consensus security proofs is a plus.
• Strong open‑source contribution history is a plus.
• Professional experience with Rust, Go, JavaScript, TypeScript, Solidity, or Python.
• Network programming experience in peer‑to‑peer contexts such as libp2p/ragep2p.
• Experience with web technologies such as HTTP.

What we offer

• Total compensation estimated between $80,000 – $160,000 per year before tax (depending on level).
• Unlimited vacation (typically 30 days per year including public holidays).
• Ability to work remotely as much as you prefer, with optional on‑site work in Athens, Greece.
• Opportunities to travel for conferences and scientific events 2‑3 times per year.
• Work and learn from world‑class scientists from major universities.
• Collaboration with senior engineers and exposure to cutting‑edge blockchain projects.
• Contributions to open‑source libraries and tools used by the broader community.
• Professional development through internal lectures, courses, and mentoring.
• Flexible working schedule and supportive culture.