Fullstack Developer(MERN Stack)

About the role

Own a service end to end its API contracts, data model, integration patterns, performance, security posture and behaviour in production. Roughly 70% backend and 30% frontend in React. You will work independently, contribute to architectural decisions, mentor one engineer, carry on-call, and act as the technical point of contact for your service with enterprise client stakeholders.

What you will do

• Own API contracts and service boundaries versioning, idempotency, backward compatibility.
• Own the data model: schema design, indexing strategy, query performance and zero downtime migrations.
• Design integration patterns between services, including asynchronous messaging where appropriate.
• Own caching with a real invalidation approach, and service performance N+1 removal, slow-query tuning, latency percentiles.
• Own security (object-level authorisation, validation, secrets, dependency risk) and observability (structured logs, metrics, traces, actionable alerts).
• Carry on-call, debug production incidents across service boundaries and author the root cause analysis.
• Own the test strategy and contribute to CI/CD, release strategy and rollback safety.
• Mentor one engineer, review pull requests, and explain architecture and delivery risk to clients.

What we are looking for

• 3+ years of backend experience with Node.js and TypeScript in production.
• Strong NestJS or equivalent modules, dependency injection, guards, interceptors, pipes, exception filters.
• Demonstrated ownership of API and service design, including versioning and idempotency.
• Deep PostgreSQL: schema design, EXPLAIN plans, index strategy, transactions, safe migrations. Working MongoDB experience.
• Production Redis or equivalent caching, with an invalidation strategy. Production asynchronous messaging (Kafka or RabbitMQ) consumer groups, ordering, retries, dead-letter handling.
• Practical ownership of security (OWASP Top 10, authorisation models, secrets) and observability (logging, metrics, tracing, alert design).
• Working AWS (ECS/EKS or Lambda, S3, RDS, SQS/SNS, IAM, CloudWatch), Docker and CI/CD with release and rollback ownership.
• Daily use of AI coding assistants (Cursor, Claude, GitHub Copilot or equivalent) prompt and context engineering, spec-driven development, and the judgement to verify output and catch AI-introduced defects in review.
• Evidence of mentoring and high-quality code review, and confident English for direct client communication.

Also part of the role (~30% frontend)

• Strong working knowledge of React and TypeScript — component design, hooks, state management, reusable UI patterns.
• HTML5 and CSS3, responsive design, browser behaviour and accessibility fundamentals.
• Integrating with REST and GraphQL APIs, handling loading, error and empty states.
• Debugging with browser developer tools; awareness of re-render, bundle and API-call performance issues.
• Reviewing and validating AI-generated frontend code, not just backend code.

Nice to have

Agentic AI frameworks (LangGraph, CrewAI, PydanticAI)

• OpenAI SDK • MCP • RAG and vector databases • Python • Kubernetes • Terraform or CDK • event sourcing, CQRS, outbox or saga patterns • multi-tenancy at scale • feature flags and progressive delivery • load testing • GraphQL server design