Senior Fintech Full-Stack Engineer — Build & Deploy Banking Platform (NestJS + React + AWS)

We are building a white-label banking and payments platform that will allow us to offer branded account management, cross-border transfers, virtual accounts and compliance screening to clients under our own brand. We have the customer-facing frontend source code (React/Vite/TypeScript), brand guidelines, Figma designs, and commercial agreements with banking infrastructure providers (Kira for FBO banking, SFOX for OTC, plus Bridge.xyz, RouteFusion and BlindPay). We also have detailed technical documentation describing the target architecture. What we need is someone to build and own the backend, deploy the full platform, and integrate the banking providers — taking this from source code and documentation to a live, production-grade product. Scope of work: Phase 1 — Backend Development (Weeks 1–8) Build the NestJS/TypeScript backend API based on existing documentation and database schema Set up PostgreSQL database with TypeORM, migrations and all required tables (users, clients, accounts, transactions, virtual accounts, beneficiaries, wallets) Implement authentication (JWT, 2FA/TOTP, password reset, role-based access for admins and clients) Build the MSB admin module (client management, branding, compliance, activity logging) Build the client module (registration, KYC onboarding, profile management, wallet linking) Build the transfer and transaction module (orchestration, status tracking, webhooks, real-time updates via WebSocket) Implement file upload service (AWS S3) and email service (Resend) Build compliance gate (sanctions screening, tiered document review) Phase 2 — Banking Provider Integration (Weeks 6–12) Integrate Kira banking API (FBO accounts, SWIFT transfers, customer onboarding) Integrate Bridge.xyz (wallets, virtual accounts, crypto on/off ramp, external accounts, transfers) Integrate RouteFusion (cross-border entity management, beneficiaries, international transfers) Integrate BlindPay (bank transfer processing, payin/payout) Implement webhook handling for all providers with signature verification Build idempotency, retry logic and reconciliation between providers and our database Handle failed, reversed and duplicate transactions Phase 3 — Deployment & Hardening (Weeks 10–16) Deploy full stack to AWS (EC2/ECS, RDS, S3, IAM, VPC) Set up staging and production environments Configure HTTPS, DNS, CORS, domain routing Implement logging, monitoring, backups and recovery Production secrets management End-to-end testing of all flows (registration, KYC, account creation, transfers, webhooks) Phase 4 — Launch & Handover (Weeks 14–20) Security hardening and penetration testing coordination Final verification checklist Documentation and runbooks Handover and training Transition to ongoing maintenance retainer Requirements: 5+ years Node.js / NestJS / TypeScript backend development Strong React + TypeScript frontend experience PostgreSQL, TypeORM, database design and migrations AWS infrastructure (EC2/ECS, RDS, S3, IAM, VPC, ALB) Docker and containerised deployment Proven fintech, payments or banking platform experience — this is non-negotiable REST API design, webhook handling, idempotency patterns KYC/KYB onboarding and virtual account workflows Secure authentication (JWT, 2FA, role-based access) Transaction lifecycle management (pending, completed, failed, reversed) Excellent English communication and clear progress reporting Nice to have: Experience with Bridge.xyz, Kira, RouteFusion, Plaid or similar BaaS providers SWIFT and cross-border payment experience Compliance screening and sanctions-check API integration CI/CD pipeline setup (GitHub Actions or AWS CodePipeline) Previous experience building a platform from documentation/specs rather than greenfield This is a significant engagement and we are looking for one strong technical lead, not a team of juniors. There is a long-term retained role available after launch for the right person. Remote — UK or compatible timezone overlap preferred. Screening questions: Describe a fintech or banking platform you have built or significantly contributed to. What was your role and what banking providers were involved? Have you integrated APIs that handle real money movement (not just payment gateways)? Describe the most complex integration you have done. How do you handle transaction failures, duplicates and webhook reliability in a payments system? What is your experience deploying containerised applications to AWS? What is your availability and rate?