Senior Backend Engineer

About Our Client

Our client is a Series B fintech-infrastructure company, backed by tier-one venture investors and led by a founding team with prior exits in payments and financial services. Their platform powers payments, ledgering and money movement for thousands of businesses, and volumes have been growing quickly across multiple markets. The engineering culture is genuinely strong — small autonomous teams, high ownership, a bias to ship and a serious commitment to reliability and security. Having recently closed a significant funding round, they are investing heavily in the core platform and the team behind it. The company is kept confidential at this stage; full details, including the client name, are shared with shortlisted candidates.

Job Description

Our client is looking for a Senior Backend Engineer to design, build and scale the core services that sit at the heart of a high-throughput payments platform used by thousands of businesses every day. Working in a small, senior team, you will own critical systems end-to-end — from architecture and implementation through to reliability, performance and on-call — and have a direct hand in the decisions that shape the platform as it scales. This is a genuine ownership role for an engineer who wants their work to matter.

• Design, build and operate core backend services and public/internal APIs that process large volumes of payments and financial data
• Own the reliability, performance, scalability and observability of the services you build, including participating in a healthy on-call rotation
• Lead the design of new subsystems and contribute to key architecture decisions as the platform grows in scale and complexity
• Model and evolve data storage, ensuring correctness, consistency and auditability for money-movement flows
• Partner closely with product and design to translate requirements into well-scoped, customer-facing features
• Write clean, well-tested, maintainable code and champion strong engineering standards across the team
• Improve tooling, CI/CD and developer experience so the team can ship quickly and safely
• Investigate and resolve production issues, then invest in the fixes and safeguards that stop them recurring
• Review code thoughtfully and mentor other engineers, raising the overall quality bar
• Contribute to technical planning, estimation and roadmap discussions

The Successful Applicant

We're looking for a pragmatic, senior engineer who has built and operated meaningful backend systems and wants to keep doing so with a high degree of autonomy.

• 5+ years building and operating production backend systems at scale
• Deep proficiency in at least one of Python, Go, Java or a comparable server-side language
• Strong grounding in distributed systems, APIs and event-driven or service-oriented architectures
• Solid experience with relational and/or NoSQL databases and thoughtful data modelling
• Comfortable owning services in production — observability, alerting, on-call and incident response
• A track record of writing well-tested, maintainable code and improving the systems around you
• Clear communicator who can collaborate with product, design and other engineers
• Fintech, payments or other high-scale / high-reliability SaaS experience is a strong plus
• Experience with a major cloud provider (AWS, GCP or Azure) is welcome

What's on Offer

This is a high-impact role at a well-backed US business, with a package built to attract and retain exceptional people: