Software Engineer, Credit Card

Openkrill; United States; Remote; USD 120,000 - 180,000; Full time

Benefits offered by this job

Competitive base salary

Stock options

Health benefits from Day 1

401(k) plan with company match

Remote-friendly (US)

Flexible time off

growth opportunities

Job summary

OnePay is seeking a Backend Engineer for the Credit Card team to build and maintain backend services powering the co-branded credit card product. You will design APIs and event-driven systems, ensuring secure handling of sensitive financial data at scale.

You will partner with risk, compliance, and platform teams to meet regulatory requirements and own reliability for real-time transaction processing. This role emphasizes scalability, security, and delivering fast, dependable software.

Qualifications

• 3+ years of backend or distributed systems development.
• Experience building APIs and microservices in fintech or regulated environments.
• Proficiency in modern backend frameworks and cloud-native architecture.
• Strong understanding of data security and PCI compliance.

Responsibilities

• Design and build backend services powering the co-branded credit card product.
• Architect APIs and event-driven systems for secure data handling at scale.
• Collaborate with risk, compliance, and platform teams to meet security requirements.
• Own reliability and performance for real-time credit transaction processing.
• Drive system design decisions balancing scalability, security, and speed.

Skills

Backend development

Node.js/TypeScript

NestJS

Cloud: Kubernetes/AWS

Data security/PCI

Tools

Typescript

Node.js

NestJS

Kubernetes

AWS

React Native

Job description

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
• Comfortable operating in motion

THE ROLE

As a Backend Engineer on the Credit Card team at OnePay, your work will directly shape the infrastructure behind our co-branded credit card product, holding the same bar for trust, security, and reliability as the rest of our financial ecosystem. You will:

• Design and build backend services that power our co-branded credit card product and its integrations with partner systems
• Architect APIs and event-driven systems that handle sensitive financial data securely at scale
• Partner with risk, compliance, and platform teams to ensure new features meet regulatory and security requirements
• Own reliability and performance for systems processing real-time credit transactions
• Drive technical decisions on system design, balancing scalability, security, and speed of delivery
• Mentor other engineers and raise the bar on code quality, testing, and operational practices across the team

YOU BRING

• 3+ years of professional experience in backend or distributed systems development
• Experience building and operating production-grade APIs and microservices in a regulated or high-compliance environment (fintech, payments, banking, or similar)
• Proficiency in Node.js or similar modern backend frameworks (TypeScript, NestJS, Go, or Java)
• Familiarity with cloud-native architecture (Kubernetes, AWS) and event-driven or microservice-based systems
• Strong understanding of data security, PCI compliance, or similar standards protecting sensitive financial data
• Strong communication and collaboration skills across product, risk, and platform teams
• Drive and proactivity - everyone here is a builder and executor

TOOLS WE USE

We use Typescript front to back, with node and NestJS frameworks for server code and React Native for our iOS, Android, and Web clients. We run on a highly distributed cloud-native stack with Kubernetes and AWS, and scale and resiliency are at the heart of everything we build. We also embrace agentic development, so engineers have their choice of a variety of models and agent harnesses, including Claude Code, Cursor, Codex, and more to fit their workflow. While you don't need experience with our exact stack, familiarity with modern software engineering practices will help you ramp up quickly.

WHAT WE OFFER

• 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

STANDARD INTERVIEW PROCESS

Our process varies by role. Most candidates go through:

• AI-assisted initial screen
• Interview with Talent Partner
• Technical or Hiring Manager Interview
• Team Interview
• Executive Interview
• Offer!

EQUAL EMPLOYMENT OPPORTUNITY

To build technology and products that are used and loved by people and solve real-world problems, we need to build a team with many different perspectives and experiences. We are an equal opportunity employer. We do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status. We encourage candidates from all backgrounds to apply. Applicants in need of special assistance or accommodation during the interview process or in accessing our website may contact us at [e-mail].