Protocol Engineer

Role Summary

We are seeking a Protocol Engineer with an expertise in cryptography, blockchain, zero-knowledge systems, and Rust.

The role focuses on designing, implementing, optimizing and actualizing the core proving systems, circuits, cryptographic primitives, and protocol logic powering Nullmask.

• Assist with design and implementation of zkSNARK-based components and proving systems (Noir and Rust, currently we use Ultra Honk, we will probably switch to Jolt)
• Develop cryptographic primitives and libraries in Rust
• Translate research into specification for developers
• Implement Solidity smart contracts for on-chain protocol components
• Optimize zk-circuits and E2E protocol latency
• Investigate overall protocol privacy and possible attack vectors
• Conduct security reviews and cryptanalysis of critical components
• Contribute to documentation, specifications, and protocol design
• Collaborate across research, backend, and product teams

• Solid understanding of linear algebra, finite fields arithmetic, field extensions,
• polynomial interpolation
• Elliptic curve fundamentals (group law, curves, scalar arithmetic)
• Basic knowledge of curve cycles and pairings

• Polynomial algorithms (FFT/NTT)
• Big integer arithmetic (Montgomery, Karacuba)
• Basic computational algebra concepts (symbolic computation)

• Solid knowledge of provable security & reductions
• Commitment schemes (Pedersen, KZG, IPA, Merkle)
• Signature schemes (ECDSA, Schnorr, BLS)
• Hash functions (Poseidon2, Keccak, SHA-256, etc.)
• Merkle trees (sparse, incremental)
• Symmetric & asymmetric cryptography
• Elliptic-curve cryptography fundamentals and applications

• Solid understanding of zkSNARK
• Familiar with Fiat–Shamir transformation
• Polynomial commitments, IOPs, ZKG
• Protocol Engineer 2 Familiarity with basic differences between:
  • Groth
    16
  • Plonk / Plonkish
  • Plonky2
  • zkSTARKs & FRI

• Basic understanding of concept of recursive proofs:
  • Accumulation schemes (Halo2, Ultra Honk)
  • Folding schemes (Nova, Hyper Nova, Cycle Fold)
  • Familiarity with zkVMs / zkEVMs

• Solid understanding of circuit design and arithmetization

range checks, custom gates, lookup tables

• Basic understanding of R1CS, Plonkish, AIR

• Solid understanding of Ethereum:

Transaction format, gas model, EVM architecture

Precompiles, storage, calldata, logs

Token wraping

L2 solutions (zk Rollups, optimistic rollups, validiums)

• Bridges (native, Wormhole), message passing (e.g. Layer Zero)
• Liquidity pools and AMM fundamentals

Privacy protocols (Zcash, Monero, Tornado, Railgun):

Nullifiers, Merkle trees, UTXO model, inclusion proofs

• Basic understanding of compliance in privacy-preserving systems

• Advanced proficiency in Rust (async, traits, borrowing, performance)
• Basic proficiency in JavaScript/Type Script
• Familiarity with Solidity
• Git & Git Hub workflows

• Experience with Arkworks, Halo2, Plonky2, Circom, or Nova
• Experience with zkVMs (Risc-0, SP1, Jolt, Cairo, Lurk)
• Experience building privacy systems (mixers, stealth addresses, MPC)
• Strong background in security audits or protocol design
• Systems engineering (Linux, networking, low-level optimization)
• Experience contributing to open-source cryptography projects
• Understanding of account abstraction (EIP-4337) and private wallets

• Work on cutting-edge cryptography and ZK systems
• Direct collaboration with senior cryptography talent
• Greenfield protocol design — minimal legacy constraints
• High personal impact on a core privacy technology
• Opportunity to shape a new privacy standard for Ethereum