Full Stack Engineer

As a Full Stack Engineer on our Lending team, you’ll help deliver impactful projects at scale and support the technical direction of lending products that reach millions of customers., * Contribute to the design and implementation of projects that power our lending platform

• Collaborate with cross-functional partners, including product, design, and operations, to build seamless lending experiences
• Write clean, reliable code and participate in code reviews
• Support the optimization of lending systems for performance and scale
• Learn and follow best practices in architecture, code quality, and scalability
• Participate in knowledge sharing and team discussions, We use Node and TypeScript on the server, leveraging the NestJS framework in a microservice-oriented architecture running on Kubernetes and AWS. On the client side, we build and ship features for iOS, Android, and web platforms using React Native. We also embrace AI-assisted development, so engineers have their choice of Claude Code or Cursor to fit their workflow. Experience with our exact stack isn’t required-familiarity with modern software engineering practices will help you ramp up quickly.

• 3-8 years of experience building and scaling distributed systems, high-throughput APIs, or data-intensive services
• Solid hands-on full-stack engineering skills, with proficiency in backend architecture and modern frontend frameworks
• Experience designing or working on reliable, secure, and high-performance systems-ideally in payments, lending, or other regulated consumer finance domains
• Clear communication skills and a collaborative working style
• Initiative and growth mindset-eager to learn and contribute as a team player

• Competitive base salary, stock options, and health benefits from Day 1
• 401(k) plan with company match
• Remote-friendly (US), flexible time off (FTO), and opportunities for growth
• A high-growth, mission-driven, inclusive culture where your work has real impact

About OnePay

OnePay is the consumer fintech trusted by millions of Americans to make money better.

Our financial system is broken. High fees, low rates, and too few ways to actually grow your money. We’re fixing it. And we’re moving fast.

We’re an all-in-one financial services platform that brings together banking, high-yield savings, credit cards, point-of-sale lending, investing, and crypto in one place. We also partner with employers, HCM providers, gig platforms, and others to deliver embedded financial services to millions of employees and frontline workers.

We’re backed by Walmart, the world’s largest retailer, and Ribbit Capital, one of fintech’s most respected investors, giving us rare scale, distribution, and the opportunity to build something truly category-defining.

But what really sets OnePay apart is how we move. Our customers don’t have time to wait… and neither do we. This place moves fast, and we’re looking for people who are:

• Ready to run
• Hungry and driven by urgency
• Exceptional at what they do, with low ego