Job Description
Senior Backend Software Engineer - FinTech
£120,000 + Share Options & Benefits Flexible office policy | South London
Tech Stack: Node.js · TypeScript · AWS · Kubernetes · REST APIs
I'm partnering with a high-growth UK payments fintech that's fundamentally rethinking how merchants and consumers pay for goods and services.
This isn't a company doing incremental work, they're building genuinely disruptive infrastructure at scale, and they're now bringing on multiple Senior Engineers to help define the next chapter of growth.
The Engineering Environment
A modern, cloud-native platform engineered for serious scale:
* Node.js, TypeScript
* React (frontend)
* AWS cloud infrastructure
* Kubernetes
* Terraform (Infrastructure as Code)
Architecture Highlights
* Event-driven, distributed systems (EventBridge, SQS)
* Public-facing REST APIs
* Fully automated CI/CD pipelines
* Data science and ML-driven personalisation
* Scalable B2B payments infrastructure
The Role
As a Senior Software Engineer, you'll be working be shaping architecture, not just implementing it:
* Lead the design and evolution of B2B APIs and payments infrastructure
* Contribute to architectural decisions across distributed systems
* Partner with Product and UX during discovery and solution design
* Own features end-to-end, from concept through to production
* Mentor engineers and raise the bar on engineering standards
* Champion best practices across testing, CI/CD, and security
What They're Looking For
* 8+ years in software engineering, with at least 2 years in financial services (payments, banking, or wealth) or a high-volume transaction environment (eCommerce, gaming, betting, or streaming)
* Strong backend engineering experience with Node.js and TypeScript
* A track record of building and maintaining public REST APIs
* Solid AWS experience (Terraform a plus; Kubernetes a strong bonus)
* Comfort working within distributed, event-driven architectures
* A delivery-focused mindset as you take ownership and see things through
* At ease in fast-moving, scale-up environments where ambiguity is the norm