Senior Backend Engineer (L5) - Banking

About Us OpenFX is on a mission to move money as freely as data, unrestricted by time zones, banking hours, or legacy systems. We are building the infrastructure that will power the next generation of cross-border payment systems for institutions. The team's execution has been exceptional, and we're scaling at a remarkable pace. Our stellar early team comes with experience in companies like J.P. Morgan, Goldman Sachs, FalconX, PayPal, Affirm, Polygon, Kraken, Nium & others. We're backed by Accel, Lightspeed, NfX and other top-tier investors. Role Overview We're hiring a Staff Software Engineer for our Banking team. This is the senior-most individual contributor role on the systems at the core of how OpenFX holds, moves, and accounts for money- ledgers, payouts, reconciliation, and settlement. It is a hands-on technical leadership role where correctness is non-negotiable and the cost of a defect is measured in real money. You will report to an Engineering Manager and work closely with engineers, product, and other functions across the company. You will set the technical direction for the banking core, lead the hardest money-path problems, and raise the bar for how we build. This role requires someone who has built and operated financial or other correctness-critical systems in production. If your experience is limited to systems where occasional data inconsistency is acceptable, or where you have not owned something end to end for a meaningful stretch, this will be a stretch. Key Responsibilities • Own the technical direction for the banking core: ledgers, payouts, reconciliation, and settlement. • Lead architecture reviews for new financial systems and high-risk changes where correctness and auditability matter most. • Define and maintain the standards for money-handling code — idempotency, consistency guarantees, audit trails, and safe data migrations. • Design and build shared banking foundations, and reduce the systemic technical debt that slows other teams down. • Own the reliability and observability bar for money flows, and lead incident response when it matters. • Mentor senior engineers and help set what great looks like when hiring. • Partner across product, finance, compliance, and risk, translating technical trade-offs for non-engineering audiences. What We Are Looking For Must-haves: • Significant experience as a senior or staff-level backend engineer, with a track record of owning complex systems in production. • Deep expertise in distributed systems and a strong grasp of reliability, performance, and scalability trade-offs. • Sound judgment on correctness under failure — retries, idempotency, and safe handling of critical data. • Excellent technical communication and the ability to lead initiatives across teams without formal authority. • Fluency in a modern TypeScript / Node backend stack and cloud infrastructure. What helps you stand out: • Experience building or operating a production double-entry ledger. • Experience with payout or payment systems — multi-rail, multi-currency, FX, and payment lifecycle modelling. • Experience with durable workflow or orchestration engines for long-running processes. • A strong observability practice on financial or other high-stakes flows. • Prior experience at a fintech or financial services company navigating regulatory complexity. What Success Looks Like • The banking core — ledgers, payouts, reconciliation, and settlement — is correct, auditable, and resilient under failure. • Architectural decisions hold up without fundamental rework within 12 to 18 months. • Engineers across the team ship faster because of the shared foundations, standards, and tooling you've built. • Money-path incidents are rare, detected early, and recoverable — not surprises discovered in reconciliation. • You've raised the technical ceiling of banking engineering at OpenFX, not just delivered individual projects. What We Offer • Competitive salary and benefits package. • Equity in a rapidly growing company. • Opportunity to work in a fast-paced startup at the forefront of fintech innovation. • Opportunity to make a significant impact on global financial infrastructure. • Collaborative work culture with emphasis on personal and professional growth. We are committed to building a diverse and inclusive workplace. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability, or veteran status.