Senior Web3 Engineer

Department: Engineering

Location: United Kingdom

Employment Type: FullTime

About Project Eleven

Project Eleven is an applied lab of builders and technologists working at the intersection of quantum computing and cryptography. We build impactful solutions that push the digital-asset ecosystem to a more secure future. Our focus is post-quantum migration: upgrading wallets, identity, and settlement rails to quantum-safe primitives without breaking UX, composability, and developer workflows.

Our mission is to future-proof digital assets and preserve self-sovereignty in a post-quantum world. We do that by building the canonical tooling and products teams can adopt: crypto-agile infrastructure, reference implementations, and integrations that fit real constraints like latency, cost, compatibility, key rotation, and recovery.

We work with leading ecosystems to make this migration real through products we build, audits, testnets, and cutting edge research. The vision we are have is clear: a proven upgrade path, production-ready tooling and users retaining control of their assets and identity, before CRQC exists.

The role

We're looking for a Senior Web3 Engineer to join our growing Product Engineering team. As a Web3 Engineer, you'll play a pivotal role in helping to build the canonical tools and products to protect digital assets and preserve self-sovereignty in a post-quantum world.

This role is a full-time, fully remote position in Europe (GMT to GMT+2).

What you'll be responsible for

• Own the development of user-facing blockchain applications with a strong focus on security, usability, and reliability

• Design and implement high-quality user interfaces for interacting with blockchain wallets and transaction flows

• Integrate frontend applications with security-critical core libraries without re-implementing sensitive logic

• Ensure safe handling of user inputs, permissions, error states, and edge cases in blockchain interactions

• Collaborate closely with backend, protocol, and security engineers to align UX with system constraints and guarantees

• Build and maintain scalable component architectures and frontend state management solutions

• Ensure applications meet high standards for performance, accessibility, and cross-platform compatibility

• Participate in usability testing and iterate on designs based on user feedback and security considerations

What you bring

• Strong proficiency in Typescript and modern frontend engineering (e.g. React or similar)

• Production experience building and publishing browser extensions

• Strong understanding of EVM/Web3 fundamentals e.g. wallet architecture, JSON-RPC, signature flows, integration with smart contracts

• Security-minded with experience working with security-sensitive code e.g. key handling, signing flows, storage, encryption

• Key experience consuming security-critical libraries

• Demonstrated ability to deliver high-fidelity UI/UX

  • Strong design skills and attention to detail

  • Experience designing component libraries and UX flows

  • Obsession with customer experience and usability testing

• High ownership and comfortable owning features end-to-end i.e. requirements → UI prototypes → Implementation → QA

• Strong English communication

What we'd love to see

• Experience with mobile development e.g. React Native, iOS development

• Experience with ERC-4337 account abstraction

• Awareness and understanding of post-quantum cryptography

• Backend experience e.g. building lightweight supporting services in Node.JS or Rust

• Prior experience using Viem and ZeroDev (or similar)

Equal Opportunity

We are committed to equal employment opportunity and believe that diverse teams build better products. All qualified applicants will receive consideration without regard to any protected characteristic under applicable law.