Protocol Engineer (Onchain Payments)

Saifuro checks payments that AI agents try to make. An agent asks to spend, we compare the request with a mandate a human approved earlier, and the answer comes back signed so the receiving side can verify it. There's escrow on Base and Solana for trades between agents, and settlement is in USDC, onchain. We never hold customer funds. The docs are public at docs.saifuro.com, and the people who use them are developers building agents and the teams selling APIs to those agents.

An agent can pay over x402 from Coinbase, AP2 from Google or ACP from Stripe and OpenAI, and each protocol carries a payment its own way. Saifuro checks every payment against its mandate the same way, whichever protocol it arrives on, and answers in a form that protocol understands. That layer is this job: the adapters for each protocol and the routing between them. Call it protocol developer or payments infrastructure engineer if you prefer. You work directly with our CTO.

What you'd be doing

• The adapters. Own Saifuro's support for x402, AP2 and ACP, from the payment request an agent sends to the signed verdict the seller checks. The specs are still young, and you keep us current as they change.
• Routing. Build the layer that sends each payment over a protocol the seller accepts, so an agent never has to care which one it is.
• What's next. Early next year our signed verdict moves to version 2, and agent identity follows later in 2027. You'll help design both from the first draft.

What we need from you

• You write production code in TypeScript or Go, and you're happy to work in both.
• You've built against a specification, such as a payments API, an open standard or a network protocol, and you read a spec closely enough to find its gaps.
• You live in one of the countries we can hire in.

Beyond these requirements, we'll support you in learning whatever else the role demands. If your experience is relevant but your title differs, we would still like to hear from you. Work outside a job counts too: open source, hackathons and your own projects.

It helps, but isn't required, if you've built with x402, AP2 or ACP, even as a side project, if you've opened issues or pull requests on x402, AP2, A2A or MCP, if you've integrated a card network or a payment processor, if you know EIP-712 or EIP-3009, or if you've worked with USDC on Base or Solana.

Countries we can hire in

The role is fully remote. You can live and work in any of the countries below.

• Americas. Argentina, the Bahamas, Brazil, Canada, Chile, Colombia, Costa Rica, Dominican Republic, Ecuador, Guatemala, Mexico, Panama, Paraguay, Peru, the United States (including Puerto Rico), Uruguay.
• Europe. Albania, Austria, Belgium, Bosnia and Herzegovina, Bulgaria, Croatia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Monaco, Montenegro, the Netherlands, North Macedonia, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey, the United Kingdom (including Jersey, Guernsey, the Isle of Man, Gibraltar, Bermuda, the Cayman Islands and the British Virgin Islands).
• Middle East and Africa. Bahrain, Israel, Kuwait, Mauritius, Oman, Qatar, Saudi Arabia, South Africa, the United Arab Emirates.
• Asia-Pacific. Australia, Brunei, China (including Macau), Hong Kong, India, Indonesia, Japan, Malaysia, New Zealand, the Philippines, Singapore, South Korea, Taiwan, Thailand, Vietnam.

Pay and benefits

• Salary $170,000 to $230,000. That's the US range. Outside the US we pay in USD, or in USDC if you'd rather, and set the offer against the top of the local market.
• Equity: 0.35% of Saifuro, vesting.
• Health: 100% of medical, dental and vision premiums for US employees, 75% for dependents. Outside the US, the local plan through our employer of record, or $300 a month toward private cover.
• 25 days of paid vacation plus your public holidays, and we close between Christmas and New Year.
• 14 weeks of paid parental leave, for any parent.
• A laptop and $1,000 toward your workspace.
• $1,500 a year for learning, conferences included. That's on top of the events you'll attend for work: six to eight a year, planned a quarter ahead, on the company.

Hours are flexible. The one thing we ask is to be online from 14:00 to 17:00 UTC, when the team overlaps for calls and quick questions. That's a window, not the working day. The rest of your hours are yours to arrange. A mainnet incident doesn't keep office hours. If that window is the middle of your night, say so and we'll work something out.

You can combine this with a job at another company, as long as the two don't conflict.

How to apply

Email contact@saifuro.com with the subject "Protocol Engineer". Attach your resume and include links to your GitHub and LinkedIn profiles, as well as X or a personal site if you have them. Let us know your country of residence. We'll reply with the next steps.