Senior Blockchain Engineer

MoonPay

About MoonPay MoonPay is for builders with something to prove. This isn't a "work on cool crypto stuff" company. It's a high-standards, high-velocity, high-accountability company building the operating system for value movement. If the internet moves information, we move value: crypto, stablecoins, tokenized assets, and whatever comes next. Four offerings make that real: fund, tokenize, trade, and spend. 30M+ customers and 500+ ecosystem partners run on us. Licensed in the U.S. Regulated across the UK, EU, Canada, and Australia. AI is the default operating mode here. It's woven into every role, and we expect you to use it daily. It handles the manual work so you can deliver on what actually matters. You'll thrive here if outcomes excite you more than process, if impact motivates you more than titles, and if you want hard problems, real ownership, and teammates who love winning, building, and doing it together. The bar is high. The pace is real. We're building for what's next, for humans and agents. Recent recognition: Forbes' America's Best Startup Employers 2026 . 2nd in Crypto Services on Fortune's inaugural Crypto 100,  The Sunday Times Best Places to Work two years running. Research has shown that women are less likely than men to apply for this role if they do not have experience in 100% of these areas. Please know that this list is indicative, and that we would still love to hear from you even if you feel that you are only a 75% match. Skills can be learned, diversity cannot. ______________________________________________________________________________________________________ What You Will Do Transaction Infrastructure at Scale Design and improve high-volume transaction broadcasting pipelines Manage transaction lifecycle Detect, retry, rebroadcast, and safely recover stuck transactions Wallet & Lifecycle Management Contribute to wallet infrastructure and automation systems Implement safe parallel transaction handling Improve monitoring, observability, and operational guardrails Design systems with financial correctness and reconciliation and auditability in mind Cross-Chain & DeFi Integrations Build infrastructure supporting cross chain and multi step flows (fiat to on-chain and vice versa) Handle non-atomic multi-step journeys across chains Design state machines and recovery strategies for partial failure scenarios Support routing mechanics and swap execution considerations such as price impact, liquidity changes, including MEV awareness Build reliable off-chain services that interact with on-chain contracts End-to-End Engineering Ownership Participate in estimation, planning, and execution of projects, features, and integrations Develop and maintain thoroughly tested, high-quality, and performant code Collaborate closely with Product Managers to design scalable implementation strategies Contribute to reliable, maintainable systems that evolve with product needs Participate in incident response and post-mortems Improve reliability, alerting, and system resilience Continuously evolve infrastructure to support growing volume and complexity About You Must-Have Strong backend/platform engineering fundamentals Experience operating production systems with real uptime requirements Hands-on experience interacting with live blockchain networks in production Clear understanding of transaction lifecycle in at least 1 Blockchain and failure recovery You think in failure modes, not just happy paths Strong Signals You can explain a real production incident end-to-end Experience with at least 1 wallet infrastructure (Eth, Bitcoin, Solana) or custody systems Awareness of MEV, slippages, pricing impact and swap execution risks Experience with high-throughput or financial systems Bonus points Experience working at exchanges, custody providers, wallet infrastructure teams, or high-volume DeFi platforms Familiarity with UTXO-based chains (e.g., Bitcoin), including coin selection and fee bumping strategies (RBF / CPFP) Experience designing cross-chain or multi-step transaction orchestration systems Familiarity with blockchain indexing or event ingestion pipelines Understanding of common token standards (ERC-20, SPL) and interacting with smart contracts from backend services Salary Bands: $150,000 - $210,000