Blockchain Engineer — Backend / Transaction Infrastructure

MoonPay operates a unified payments platform enabling users and businesses to move between fiat and crypto through compliant, end-to-end infrastructure. The engineering team works in small cross-functional pods (4–6 engineers) focused on building scalable transaction systems, wallets, and DeFi integrations.

This role sits within backend/platform engineering and owns high-volume transaction infrastructure, wallet lifecycle systems, and cross-chain execution flows. You’ll work on production-grade systems interacting with live blockchain networks, ensuring reliability, observability, and financial correctness across non-atomic multi-step transactions.

🔹 Responsibilities

• Design and improve high-volume transaction broadcasting pipelines
• Manage full transaction lifecycle including detection, retrying, rebroadcasting, and recovery of failed transactions
• Contribute to wallet infrastructure and automation systems
• Implement safe parallel transaction handling mechanisms
• Improve monitoring, observability, and operational guardrails
• Design systems with financial correctness, reconciliation, and auditability
• Build infrastructure supporting cross-chain and multi-step transaction flows (fiat ↔ on-chain)
• Handle non-atomic transaction journeys across multiple chains
• Design state machines and recovery strategies for partial failures
• Support routing and swap execution, considering liquidity, pricing impact, slippage, and MEV
• Build off-chain services interacting with on-chain smart contracts
• Participate in estimation, planning, and execution of engineering work
• Develop and maintain high-quality, tested, and performant code
• Collaborate with product managers on scalable system design
• Contribute to system reliability, alerting, and resilience improvements
• Participate in incident response and post-mortems
• Continuously evolve infrastructure to handle increasing scale and complexity

🔹 Requirements

Must-Have
• Strong backend or platform engineering fundamentals
• Experience operating production systems with uptime requirements
• Hands-on experience interacting with live blockchain networks
• Understanding of transaction lifecycle in at least one blockchain
• Ability to design for failure scenarios, not just ideal flows

Strong Signals
• Ability to explain a real production incident end-to-end
• Experience with wallet infrastructure (Ethereum, Bitcoin, or Solana) or custody systems
• Awareness of MEV, slippage, pricing impact, and execution risks
• Experience with high-throughput or financial systems

Bonus
• Experience at exchanges, custody providers, or DeFi platforms
• Familiarity with UTXO-based chains (Bitcoin), including coin selection and fee strategies (RBF / CPFP)
• Experience designing cross-chain or multi-step transaction orchestration systems
• Familiarity with blockchain indexing or event ingestion pipelines
• Understanding of token standards (ERC-20, SPL) and backend interaction with smart contracts

🔹 Compensation & Benefits

• Competitive salary package (currency not specified)
• Equity package for all employees
• Performance-based equity bonus structure
• Moonshot award with high-value equity grants
• Unlimited holidays policy
• Remote-first or hybrid flexibility
• Private healthcare benefits
• Enhanced parental leave
• Annual training budget
• Home office setup allowance
• Remote working allowance
• Monthly product usage budget with zero-fee crypto transactions
• Employee referral program (10K USDC reward)
• Regular company offsites and hackathons