About the role

Role Overview

Join OnePay as a Backend Software Engineer (Core App). You will design, build, and ship backend services that support user-facing features across mobile and web.

Responsibilities

Design, build, and deliver backend services for user-oriented product features.
Collaborate with frontend engineers, product managers, designers, and data partners.
Lead backend technical planning and contribute to architecture decisions to improve:
- scalability
- reliability
- performance
Proactively identify opportunities to improve user experience via backend optimizations and system enhancements.
Create and maintain clear technical documentation for a growing distributed engineering organization.

Requirements

5+ years experience building and scaling backend systems in consumer technology or fintech.
Experience designing and operating distributed systems, APIs, and data flows supporting user-facing applications.
Familiarity with message brokers and event-driven systems, plus caching and performance optimization.
Demonstrated ability to lead technical execution and mentor other engineers with a strong quality bar.

Nice-to-Haves

Experience with functional programming.
Familiarity with the stack: fp-ts, Node.js/TypeScript, Kubernetes, and AWS (not required; ramp-up expected).

About ONE

ONE (OnePay) is a fintech organization building user-facing experiences across mobile and web. It operates a remote-first engineering culture and delivers backend services that power consumer product features, working closely with cross-functional teams and data partners.

Backend Software Engineer (CoreApp)

Tags