Full Stack Developer (Backend-Focused)

Role Overview

• Looking for a Full Stack Developer (backend-focused) for a London-based fintech startup building high-performance, transaction-heavy systems for enterprise clients.
• The role involves end-to-end ownership of features and working on real-world problems around payments, failures, and reconciliation.

Key Responsibilities

Backend Development (Primary Focus)

• Develop and maintain backend services using Node.js / NestJS (TypeScript)
• Design and build APIs for high-volume transaction systems
• Implement business logic related to payments, retries, and reconciliation
• Ensure system performance, scalability, and fault tolerance

Frontend Development

• Build and maintain interfaces using React-based frameworks
• Collaborate with product/design to improve usability and performance

System Design & Architecture

• Contribute to scalable system design and architecture decisions
• Work within cloud-native AWS environments
• Follow best practices for modular and maintainable code

Data & Integrations

• Work with PostgreSQL, DynamoDB, and MongoDB
• Build integrations with payment service providers and third-party APIs
• Ensure data integrity and consistency across systems

Engineering Quality

• Write clean, production-ready code
• Participate in code reviews and improve development standards
• Debug and resolve issues across the full stack

Required Skills & Experience

• 3-5+ years of experience in full stack or backend-focused development
• Strong proficiency in TypeScript and Node.js
• Experience with NestJS, Express, or similar frameworks
• Working knowledge of React or modern frontend frameworks
• Experience with SQL and NoSQL databases
• Familiarity with AWS and cloud-native development
• Strong problem-solving skills and ownership mindset
• Good communication skills (written and verbal)

Preferred Profile

• Experience working in a startup or product-driven environment, or willingness to operate in a fast-paced, high-ownership setup
• Comfortable taking end-to-end ownership of features with minimal supervision
• Ability to work in ambiguous environments and drive solutions independently

Tech Stack

• Backend: Node.js, NestJS, TypeScript
• Frontend: React
• Infrastructure: AWS (serverless / cloud-native)
• Databases: PostgreSQL, DynamoDB, MongoDB