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
