We're looking for a Senior Full-Stack Engineer to develop and maintain our suite of transfer applications. You'll work across various repositories spanning React frontends and AWS serverless backends, owning the full delivery lifecycle from feature development through to production. Critically, we want someone who can help drive the technical strategy and continuous improvement of these applications, aligning with broader company engineering standards and platform direction.
All potential candidates should read through the following details of this job with care before making an application.
Key Responsibilities
Develop and maintain multi-step transfer journeys across transfer products
Own the full stack; React frontends, AWS Lambda BFF layers, and IaC
Drive technical strategy for the transfers domain, proposing and delivering improvements that align with company-wide engineering direction
Champion continuous improvement; identify tech debt, propose modernisation, and improve developer experience
Contribute to architectural decisions around API design, infrastructure patterns, and cross-service integration
Collaborate with platform/infrastructure teams to evolve integration patterns
Support CI/CD pipelines and deployment processes across all environments (dev, staging, production)
Mentor other engineers and contribute to team-wide engineering standards
Required Skills & Experience
Backend / BFF
Node.js (v20+) with TypeScript
AWS Lambda handler development (both SST and raw CDK patterns)
API Gateway (REST/V1) - authorizers, routing, gateway responses
Middy middleware framework
Integration patterns: cross-account STS AssumeRole, Secrets Manager, DynamoDB, SNS
RESTful API design and OpenAPI specifications
AWS & Infrastructure
AWS CDK and/or SST for infrastructure as code
Core services: Lambda, API Gateway, DynamoDB, VPC, IAM, KMS, Secrets Manager, SSM Parameter Store, SNS
VPC networking - Lambda in VPC, security groups, egress configuration
Lambda provisioned concurrency and auto-scaling
Understanding of WAF and ingress routing patterns
Testing
Vitest for unit and integration testing
MSW (Mock Service Worker) for API mocking
Testcontainers experience is a plus
CI/CD & DevOps
GitLab CI pipelines; multi-stage, environment-specific deployments
Automated security scanning (Snyk or similar SAST/DAST)
Environment promotion strategies (dev ? staging ? production)
General
Monorepo experience (pnpm workspaces, npm workspaces)
Feature flagging (LaunchDarkly or similar)
OAuth/token-based authentication and authorisation flows
Strong understanding of cross-account AWS patterns
Desirable
Frontend
React (v18+) with TypeScript
React Hook Form, Zod/schema-based validation
TanStack Query (React Query) for server state management
Vite build tooling
Component library integration
Accessibility-first development
Playwright for end-to-end xsngvjr and snapshot testing
Contract testing (Pact)
Analytics integration (Adobe Analytics or similar)
Other
Experience with SST v2 (Serverless Stack) specifically
Familiarity with API gateway/ingress platforms
Experience with Cognito for machine-to-machine auth
Financial services domain experience
Experience driving technical roadmaps and aligning them with broader organisational strategy
What We're Looking For Beyond Technical Skills
Someone who proactively identifies opportunities for improvement rather than waiting to be told
Ability to articulate technical trade-offs and influence direction at a team and cross-team level
A pragmatic approach, balancing ideal solutions with delivery timelines
Comfort working across codebases with different maturity levels and patterns (SST monorepo vs CDK + separate frontend)
Strong communication skills for collaborating with platform teams, product owners, and other squads