The posting
Location: Tel Aviv — hybrid (4 days in office / 1 day remote)
Why join us
We are building a next-generation block builder that augments Ethereums capabilities, unlocks new DeFi primitives, and improves neutrality while making block participation more accessible. As a Protocol Expert youll be the steward of protocol-level systems: youll author production-grade Rust services, define how blocks are constructed and transactions are ordered, own PBS-related integrations, and partner with validators, relays and searchers — directly shaping ordering and inclusion rules, hardening deterministic simulations and safety checks, and driving measurable impact across the Ethereum ecosystem.
What youll build
A production-grade block builder platform and the off-chain infrastructure that powers it: block construction algorithms, secure low-latency builderrelay communication and bundle handling, deterministic simulation and safety tooling, and rich observability for builder performance and market effects. Crucially, you will also design and deliver a first-of-its-kind DeFi primitive that depends on our builders augmented capabilities — a concrete, production-ready demonstration of the platforms unique value to users and the wider ecosystem.
What youll own
You will work on the architecture, implementation, and operator readiness of our block building and off-chain protocol stack: Design novel block building mechanisms. Architect algorithms that optimize inclusion guarantees, value extraction, and latency while preserving fairness and censorship resistance. Own PBS & MEV-Boost integration. Drive the integration layer with relays and validators, ensuring compliance, timing correctness, and high availability. Build builder-relay infra. Implement secure, low-latency builder-relay communication, bundle handling, and safety checks for real-world operation. Research and implement ordering strategies. Invent and validate transaction ordering, bundle-inclusion rules, and timing-game mitigations that expand usable DeFi primitives. Tooling and monitoring. Create observability, dashboards, market-share trackers, and alerting to measure builder performance, relay connectivity, and on-chain effects. Run production builder services. Ensure robust deployments, deterministic simulations, safe rollouts, and incident runbooks for on-call operation. Protocol and research leadership. Produce design docs, simulations, and proposals for PBS evolution, ePBS, and other protocol upgrades; represent the team in protocol discussions.
Required (must-have)
Deep PBS / MEV expertise. Strong practical knowledge of Proposer-Builder Separation, MEV-Boost architecture, relay ecosystems and timing games. Ethereum internals. Solid understanding of consensus and execution layers (slots/epochs, fork choice, payload delivery) and EVM execution semantics. Strong systems engineering. 7 years software engineering experience, with 3 years focused on blockchain infrastructure or MEV systems. Production Rust. Proficiency building high-performance, networked services in Rust. Operational rigor. Experience running production, security-sensitive infrastructure with monitoring, testing and on-call responsibilities. Communication & influence. Able to translate protocol tradeoffs into engineering plans and to coordinate across relays, searchers and validators.
Strong pluses (nice-to-have) Prior contributions to MEV-Boost, Flashbots, or other MEV infrastructure.
Operational experience running block builders, relays, or validator integrations. Published research or talks on PBS, MEV, or Ethereum protocol design. Familiarity with proposed protocol changes (ePBS, inclusion lists, execution tickets) and prior protocol-level design work. Background in low-latency, high-integrity distributed systems (HFT, critical infra).
