Software Engineer, Agents

MoonPay is building the operating system for moving value—crypto, stablecoins, tokenized assets, and emerging payment forms. With 30 million customers and over 500 ecosystem partners, the company operates at global scale, licensed in the U.S. and regulated across the UK, EU, Canada, and Australia. MoonPay has earned recognition as one of Forbes' America's Best Startup Employers 2026 and ranks second in crypto services on Fortune's inaugural Crypto 100 list.

MoonPay operates with a high-velocity, high-accountability culture where outcomes matter more than process and impact drives decisions. The company treats AI as a default operating mode, woven into every role, enabling engineers to eliminate manual work and focus on what creates real value. You'll find yourself working alongside teammates who are motivated by hard problems, genuine ownership, and the satisfaction of shipping product that matters.

PayBox, one of MoonPay's newest products, lets people transact directly through AI agents without exposing their underlying credentials. After a strong launch, the team is now executing on the next phase: expanding across AI platforms, building peer-to-peer payment experiences, integrating with DeFi applications, growing the plugin ecosystem, and dramatically improving the end-to-end experience. MoonPay is looking for an exceptional Staff Software Engineer to take ownership of PayBox through this critical growth stage.

What you'll do

• Own significant areas of PayBox end-to-end, from problem identification and approach design through building, shipping, and iterating in production
• Move a recently launched product through its next 0 to 1 development and growth phase alongside the Chief Engineer and a small, laser-focused team
• Design and build new payment and peer-to-peer transfer experiences specifically for AI interfaces
• Integrate PayBox across AI platforms, applications, and the broader ecosystem
• Develop infrastructure and product experiences that enable new applications to onboard onto PayBox
• Partner with Product to translate ambitious ideas into simple, usable experiences
• Work across the full technical stack wherever the highest-impact problems live, from onboarding flows to core infrastructure
• Use AI extensively to amplify your speed and output while maintaining your own technical judgment and accountability for what ships

What you'll bring

• Exceptional technical reasoning with strong fundamentals; you break down unfamiliar, ambiguous problems and reason toward solid solutions
• High agency; you identify important problems without waiting for perfect requirements and take full responsibility for solving them
• Proven track record building and shipping meaningful products, projects, or systems from start to finish, not operating in narrow domains
• Deep thoroughness; you care about quality details others overlook and treat "working" as the beginning, not the end
• Strong systems thinking; you design systems, understand technical trade-offs, and make smart architectural decisions while moving fast
• Product judgment; you understand that great engineering includes the experience around the technology, not just the code beneath it
• Comfort navigating ambiguity where problems outnumber people and priorities shift
• Independent thinking in AI-native environments; you use AI aggressively as a tool but don't outsource your reasoning to it

Nice to have

• Previous experience with crypto, payments, or Model Context Protocol (MCP)
• Background in AI agent development or infrastructure