Full Stack Developer (MERN+AWS)

Senior Full Stack Developer – MERN / AWS - Short Term Contract 3 Months

Role Overview

• Senior hands-on Full Stack Developer with strong MERN, AWS and Microservices experience.
• Responsible for designing, developing, testing, deploying and supporting scalable, secure and high-quality applications.
• Strong experience working across the full SDLC, from requirements and architecture through to production and support.
• Able to make sound technical decisions, challenge designs where appropriate and mentor other developers.

Technical Requirements

• MERN Stack: MongoDB, Express.js, React.js, Node.js.
• Strong JavaScript/TypeScript and modern frontend/backend development.
• Strong experience designing and developing REST APIs; GraphQL advantageous.
• Proven experience with Microservices Architecture, including service boundaries, API communication, asynchronous/event-driven architecture, queues and distributed systems.
• Strong AWS experience including services such as EC2, ECS/EKS, Lambda, S3, CloudFront, API Gateway, IAM, CloudWatch, SQS/SNS/EventBridge and Redis/ElastiCache.
• Experience with Docker, CI/CD and Infrastructure as Code; Kubernetes/Terraform advantageous.
• Strong experience with Socket.IO/WebSockets and real-time applications.

Product / Domain Experience

• Chat & messaging: real-time messaging, notifications, presence, delivery/read status and scalable WebSocket architecture.
• Social media: profiles, feeds, followers, posts, comments, likes, notifications and media.
• E-commerce: products, catalogues, carts, checkout, orders, inventory, discounts and customer accounts.
• Payments: Stripe/Adyen/PayPal or equivalent; payment workflows, webhooks, refunds, idempotency and transaction reconciliation.
• Rideshare / mobility: driver/rider apps, matching, GPS/location tracking, trip lifecycle, ETA, pricing, payments and real-time updates.
• Experience across multiple of the above domains is highly desirable.

Engineering Standards & Quality

• Strong understanding of SOLID, DRY, clean code, design patterns, separation of concerns and maintainable architecture.
• Establishes and follows coding standards, Git/branching standards, code reviews and documentation practices.
• Strong focus on code quality, technical debt, maintainability, scalability and performance.
• Strong understanding of secure coding and OWASP principles, authentication, authorisation, API security and secrets management.

SDLC & Testing

• Strong understanding of the complete SDLC: requirements → design → development → code review → testing → deployment → monitoring → support.
• Experience working in Agile/Scrum/Kanban environments.
• Strong automated testing experience:
  • Unit testing – Jest/Mocha
  • Integration/API testing
  • E2E testing – Playwright/Cypress
  • Performance/load testing
  • Security/vulnerability testing
• Understands test strategy, automation, coverage, regression testing and quality gates.

DevOps / Production

• Strong understanding of CI/CD pipelines, automated builds, testing and deployments.
• Experience with Docker/containerisation and cloud deployments.
• Understanding of monitoring, logging, alerting, tracing and production troubleshooting.
• Strong knowledge of performance, scalability, caching, database optimisation, load balancing and fault tolerance.
• Experience with high-availability and production-critical systems.

Senior-Level Expectations

• Strong system design and architecture capability.
• Able to design scalable solutions and clearly explain technical trade-offs.
• Takes ownership from requirements through to production.
• Strong problem-solving and debugging skills.
• Conducts effective code reviews and mentors developers.
• Works closely with Product, QA, DevOps and other stakeholders.
• Maintains a strong focus on quality, security, scalability and delivery.

Essential

• Senior commercial development experience.
• MERN / JavaScript / TypeScript.
• Node.js & React.
• MongoDB.
• AWS.
• Microservices.
• REST APIs.
• Socket.IO/WebSockets.
• Automated testing.
• CI/CD & Docker.
• Strong SDLC and software engineering practices.
• Proven experience delivering production-scale applications.