Software Engineer, Blockchain

As a Software Engineer, Blockchain at HIFI, you will own on-chain systems that power a stablecoin infrastructure platform used by institutions and enterprises to move billions of dollars globally. You'll build and maintain the integrations, smart contracts, and wallet infrastructure that connect HIFI's payments products to the chains and stablecoins we support. This is a hands-on role with real ownership: you'll design how funds move and settle on-chain, work with the rest of engineering to connect those flows to the ledger and APIs, and partner with compliance on controls like wallet screening and transaction monitoring.

What you'll do

• Build wallet infrastructure, including key management, transaction signing, and orchestration across custodial and programmatic wallets
• Handle on-chain transactions across EVM chains and other supported networks, including gas and nonce management, and retries
• Develop stablecoin minting, burning, and settlement logic that connects USDC and other stablecoins to fiat rails for on-ramp and off-ramp products
• Integrate with centralized and decentralized exchanges for swaps and liquidity routing, and cross-chain bridging between networks
• Build a double-entry ledger that keeps on-chain balances, banking partners, and customer accounts in sync, with automated reconciliation
• Create event listeners, confirmation tracking, and webhooks that give the platform and customers real-time visibility into on-chain activity
• Design idempotent transaction pipelines with failure recovery and screening hooks to ensure money moves correctly even when something goes wrong
• Judge when a new chain or protocol is ready for production use

What you bring

• 3+ years of software engineering experience, including at least 1 to 2 years building blockchain systems in production
• Deep familiarity with EVM chains, including transaction lifecycles, gas mechanics, common failure modes, and enough Solidity to read and integrate contracts
• Experience with wallet architecture, such as custody models, signing services, or MPC and HSM-backed setups
• Strong backend fundamentals, including API design, data modeling, and handling consistency and concurrency in distributed systems
• You build financial systems with reconciliation and audit trails by default
• You communicate clearly in code review and in writing

Nice to have

• Experience with stablecoin infrastructure such as Circle, or with connecting on-chain and fiat settlement
• Hands-on work with CEX APIs, DEX protocols like Uniswap, or bridge integrations
• Experience building ledgers or double-entry accounting systems
• Exposure to compliance engineering, such as transaction monitoring, address screening, or Travel Rule tooling
• Experience with non-EVM chains like Solana or Tron
• Familiarity with traditional money movement, including ACH, wires, and how funds settle between banks and processors
• Early-stage startup experience building and running a system from scratch

About HIFI

HIFI is a stablecoin infrastructure company founded in 2022 that builds tools for payments and tokenized money products across money movement, cards, and capital markets. Institutions and enterprises use the platform and APIs to move billions of dollars in production environments around the world. The organization is flat and talent-dense, based in Flatiron, and has raised $37 million from investors including Left Lane Capital.