JOB TITLE & HOOK: Senior Backend Engineer — Own the ledger that every payment depends on, and shape the API for the company's next lending product from day one. ABOUT THE ROLE: You'll take technical ownership of our payments ledger service while helping define the backend architecture for a new lending product. Day to day, you'll design reliable systems, make pragmatic engineering decisions, mentor two mid-level engineers, and join the on-call rotation to keep critical services running. We're a 40-person Series B fintech, so the code you write and the decisions you make will be visible across the company. RESPONSIBILITIES: - Own the payments ledger service, ensuring correctness, reliability, and operational stability. - Design and deliver the backend API for a new lending product, balancing developer experience with long-term maintainability. - Build and improve distributed services that process and store financial data with a strong focus on consistency and performance. - Mentor two mid-level backend engineers through technical reviews, architecture discussions, and day-to-day coaching. - Participate in the on-call rotation, troubleshoot production issues, and improve systems to reduce recurring incidents. - Work closely with product and engineering teammates to turn evolving requirements into production-ready technical solutions. - Drive technical decisions, identify areas for improvement, and take ownership from design through deployment and operation. REQUIREMENTS Must-Have: - 5+ years of professional backend engineering experience. - Strong proficiency in Go or Java. - Hands-on experience building and operating distributed systems. - Experience working with financial data or payment-related systems where accuracy and reliability are critical. - Comfortable making sound technical decisions when requirements are still evolving. Nice-to-Have: - Experience designing public or internal APIs for financial products. - Background in fintech, lending, payments, or banking platforms. - Experience mentoring engineers and helping teammates grow. WHAT WE OFFER: - Compensation: Competitive salary (Insert Salary Range) plus equity. - Comprehensive health and wellness benefits. - A small, experienced team where ownership matters more than job titles and your work has visible impact. - Flexible working arrangements and the autonomy to make technical decisions. - The opportunity to help shape core financial infrastructure during a key stage of company growth. SHORT SOCIAL VERSION: We're hiring a Senior Backend Engineer to own our payments ledger service and lead the API design for a new lending product. If you have 5+ years of backend experience, strong Go or Java skills, and you've built distributed systems that handle financial data, we'd like to talk. Apply to join a 40-person Series B fintech where ownership matters and your work is visible from day one.