Fullstack Developer(MERN Stack)

Indexnine; Pune District; On-site; INR 900,000 - 1,300,000; Full time

Job summary

Indexnine seeks a backend-focused engineer to own a service end-to-end, including API contracts, data model, and production performance with roughly 70% backend and 30% frontend in React. You will work independently, mentor one engineer, and act as technical contact for enterprise client stakeholders.

Requirements include 3+ years of Node.js/TypeScript production work, strong NestJS, PostgreSQL, Redis, and AWS/Docker/CICD familiarity, plus React/AI-assisted frontend skills.

Qualifications

• 3+ years of backend experience with Node.js and TypeScript in production.
• Ownership of API design, versioning and idempotency.
• Deep PostgreSQL/schema design and safe migrations; MongoDB experience.
• Production Redis caching, Kafka/RabbitMQ messaging, and observability.
• Working AWS, Docker, and CI/CD with release ownership.

Responsibilities

• Own API contracts, data model, and integration patterns end-to-end.
• Handle on-call, debug production incidents, and perform root-cause analysis.
• Mentor one engineer and review pull requests; communicate risks to clients.
• Design test strategy, contribute to CI/CD, and manage releases.

Skills

Backend development

Node.js

TypeScript

NestJS

API design

PostgreSQL

Redis

AWS

Docker

CI/CD

React

Mentoring

On-call

Tools

PostgreSQL

MongoDB

Kafka/RabbitMQ

Redis

AWS ECS/EKS/Lambda

S3

CI/CD tooling

Job description

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