Blockchain Developer

About the Role We're looking for a mid-level Blockchain Developer to design, build, and maintain decentralised applications and smart contracts. You'll work alongside engineers, product, and security teams to ship reliable on-chain solutions — from writing and auditing smart contracts to integrating them with backend services and front-end interfaces. This is a hands-on role for someone with production blockchain experience who wants to deepen it. You'll own features end to end, contribute to architecture decisions, and help raise the quality of everything we deploy. Key Responsibilities • Design, develop, and deploy smart contracts, primarily in Solidity, and integrate them with off-chain systems. • Build and maintain decentralised applications (dApps), including the APIs and services that connect them to the blockchain. • Write clean, well-tested, and gas-efficient code, with a strong focus on security and correctness. • Participate in code reviews and internal audits, and help remediate findings from external security reviews. • Integrate with EVM-compatible networks and interact with wallets, oracles, and third-party protocols. • Develop and maintain automated tests, deployment scripts, and CI/CD pipelines for on-chain and off-chain components. • Monitor deployed contracts and services, troubleshoot issues, and support incident response. • Document technical designs and contribute to shared engineering standards and best practices. Required Skills & Experience • 7-9 years of software development experience, with at least 3 years working on blockchain or Web3 projects. • Solid hands-on experience with Solidity and the Ethereum / EVM ecosystem. • Experience with development frameworks such as Hardhat, Foundry, or Truffle. • Strong grasp of smart contract security practices and common vulnerability patterns (re-entrancy, overflow, access control, etc.). • Proficiency in at least one general-purpose language such as JavaScript / TypeScript, Python, Go, or Rust. • Experience building backend services with NestJS or a similar Node.js framework, including REST/GraphQL APIs that connect on-chain components to internal systems. • Familiarity with Web3 libraries such as ethers.js or web3.js. • Experience integrating smart contracts with institutional/custodial wallet infrastructure (e.g. Fireblocks, Copper, Anchorage, BitGo, or multi-sig/MPC custody solutions), including multi-sig transaction flows, EIP-712 typed signing, and transaction approval/policy workflows. • Strong understanding of blockchain internals — consensus mechanisms, gas, transactions, and token standards (ERC-20, ERC-721, ERC-1155). • Experience with Layer 2 scaling solutions, including zero-knowledge proof concepts (validity proofs, zk- SNARKs) as used in ZK-rollup networks (e.g. Polygon zkEVM, zkSync, Starknet, Scroll), and familiarity with cross-chain interoperability models built on proof verification (e.g. AggLayer, LayerZero, Chainlink CCIP) and non-EVM ecosystems (Solana, Cosmos, Polkadot). • Ability to read and navigate Go-based blockchain client codebases (e.g. L2 node/client implementations such as zkEVM nodes, op-geth, or Cosmos SDK-based clients) to debug and understand node behaviour. • Experience with DeFi, NFT, or tokenisation projects. • Familiarity with oracles (Chainlink), IPFS, or The Graph. • Experience with Git and collaborative development workflows. Nice to Have • Front-end experience (React or similar) to complement backend work and support end-to-end delivery. • Contributions to open-source blockchain projects. • Awareness of relevant regulatory and compliance considerations in the Australian market.