Senior Smart Contract Engineer

As a Senior Smart Contract Engineer at CoinList, you will build smart contracts that integrate with different asset providers to act as proxies between users and underlying assets, offering a common interface for product development. You join a small engineering team reporting directly to the CTO in a greenfield-heavy environment where your work directly affects velocity, company direction, and revenue.

What you'll do

• Ship contracts to mainnet on EVM chains, reviewed by external auditors, deployed, and holding user funds while maintaining a high technical bar
• Design contract systems from the ground up, including boundaries, interfaces, storage layout, upgrade strategy, access control, and emergency paths
• Own meaningful work as part of a small team, whether contracts behind critical token sales or leading onchain work on new products
• Treat security as the core of the job through adversarial code review, fuzzing and invariant tests, testnet deployment rehearsals, and monitoring and incident response
• Rapidly grow and improve by working with smart engineers who love to learn and teach each other, including extending your craft to Rust and the Solana runtime if you wish

What you bring

• Over 7 years of professional working experience, including at least 2 years writing Solidity that reached production
• Deep knowledge of the EVM: storage layout and packing, gas mechanics, memory versus calldata versus storage, ABI encoding, events and indexing, contract size limits, and the tradeoffs within each
• Mastery of modern Solidity patterns: proxies and upgradeability, role-based access control, signature verification and replay protection (EIP-712), reentrancy and oracle or price-manipulation defenses
• Real tooling and testing discipline with Foundry (preferred) or Hardhat, fork tests, fuzzing and invariants, and a testing workflow you can justify from first principles
• An attacker's mindset: you ask what a flash loan, an MEV bot, or a malicious token does to your code and document what you find before shipping
• A commitment to high-quality code, meeting your own deadlines, moving fast, focusing on what matters, and pushing back on what doesn't
• AI fluency: you integrate AI tools into your daily workflow naturally to move faster
• Product mindedness: you care about what you're building and why, not just how
• Independence and collaboration: you can move fast on your own and know when to loop others in
• Comfort with ambiguity and strong written communication, especially important in a distributed, remote-first team

Nice to have

• Rust and Anchor, or Solana programs in production: SPL tokens, program-derived addresses, token extensions, compute-unit optimization
• DeFi protocol depth: lending, AMMs, vaults (ERC-4626), staking and reward accounting
• Account abstraction (ERC-4337): smart accounts, paymasters, bundlers

What we offer

• Base salary of $170,000 to $190,000 based on experience and jurisdiction
• Equity as a significant part of your total compensation
• Medical, dental, and vision coverage at no monthly cost (US only)
• Unlimited PTO
• Monthly AI tool budget
• Fully remote, U.S. based, with primary presence on the US East and West Coasts; you should be comfortable overlapping some hours with non-US time zones to work with employees abroad

About CoinList

CoinList is building the distribution network for onchain capital markets through its Passage platform, which provides infrastructure for wallets, apps, and platforms to embed access to tokenized assets including equities, funds, token sales, and real-world assets. With a network of over 12M investors and more than $1.2B in transactions, CoinList operates both Passage (B2B Infrastructure for compliant raises via APIs and SDKs) and the Consumer Marketplace, the world's leading destination for token sales and on-chain investments.