Senior Protocol Engineer

Role overview Build and operate core components of a Bitcoin-secured Layer 2 rollup. This hands-on protocol engineering role spans execution, consensus, sequencing, block derivation, bridges, and proofs. You will work with a small, experienced team, take part in technical decisions, and help deliver changes safely to a live public network.

Responsibilities - Design and maintain protocol components, including execution and consensus clients, the sequencer, block derivation, and batch submission to the parent chain. - Develop bridge and proof-system functionality for deposits, withdrawals, cross-layer messages, and state validation. - Make safe, maintainable changes in a large open-source codebase. - Review code, write design documents and RFCs, and contribute to architecture decisions. - Test and debug distributed-system behavior, including reorgs, node desynchronization, adversarial cases, and performance issues. - Coordinate releases, upgrades, monitoring, and incident response with product, operations, and security colleagues.

Requirements - At least five years of professional software engineering experience, including two or more years in blockchain protocol or core development. - Production experience with a mainstream programming language such as Go, Rust, or Java. - Deep understanding of blockchain internals and the EVM, including consensus, peer-to-peer networking, state and storage, transaction lifecycle, and JSON-RPC. - Ability to work effectively in a large codebase written by others. - Autonomy, ownership of delivered work, and good spoken and written English. - Use of AI-assisted development as part of the engineering workflow while taking responsibility for results.

Nice to have - Go or Rust experience; Ethereum Layer 2 rollup or rollup design knowledge; or open-source blockchain contributions. - Familiarity with fault or validity proofs, Bitcoin and EVM-compatible chains, Docker, cloud platforms, Prometheus, or Grafana. - Ability to read and review Solidity contracts.

Benefits and work setup - Fully remote across Europe and Latin America, with access to coworking spaces. - Paid vacation and sick leave, learning support, and language courses.