Fullstack Engineer

About the Role

Koalafi is building a net-new Non-Prime Installment Loan product — a greenfield initiative that expands our financing options for customers who don't fit traditional prime credit profiles. This is a meaningful product with real impact: more customers funded, more merchants closing sales they'd otherwise lose.

You'll be part of a focused product team (product manager + tech lead + engineers) responsible for integrating Koalafi's platform with a third-party loan servicing system and building the internal capabilities to support the full loan lifecycle — origination, servicing, payments, and communications. You'll be doing real work on a real product from day one, not maintaining something someone else built years ago.

That said, this isn't a build-in-a-vacuum situation. The NPIL product connects to existing Koalafi systems — origination, payments, communications — and you'll need to be comfortable rolling up your sleeves and navigating code you didn't write. That's the job. The ability to read an unfamiliar codebase, understand its intent, and make a clean change is just as important as building new things.

What You'll Do

Build and Deliver

• Implement microservices and event-driven workflows to integrate Koalafi's systems with a third-party loan servicing platform
• Build and maintain REST APIs that support loan origination, payment processing, and customer servicing operations
• Navigate and contribute to existing internal services where the NPIL product intersects with current Koalafi systems — reading unfamiliar code, understanding its intent, and making clean, well-scoped changes
• Develop frontend components in React/TypeScript to support customer-facing and internal tooling as needed
• Write code that is testable, observable, and built to last — not just built to ship

Collaborate and Contribute

• Work closely with the Tech Lead on system design and integration architecture
• Partner with Product and Compliance to understand requirements and translate them into reliable, compliant implementations
• Participate in code reviews — both giving and receiving feedback with the goal of raising the bar, not just checking a box
• Engage actively in sprint ceremonies: planning, retros, standups — contribute to the team's rhythm, not just your own ticket

Maintain and Improve

• Implement monitoring and alerting at integration points so issues surface before customers notice them
• Support audit logging and data reconciliation requirements inherent to a regulated financial product
• Identify and flag technical risk early — bad news early is always better than bad news late
• Leverage AI development tools to move faster and stay consistent with team patterns

About You

• 2–4 years of professional software engineering experience
• Hands-on experience building backend services in Golang
• Working knowledge of REST APIs, HTTP/JSON patterns, API authentication including bearer tokens and OAuth flow