Job highlights

- Must understand asynchronous behaviour deeply,not just syntax . TypeScript - Typing components,props,API responses,generics,interfaces vs types

JavaScript (core) - ES6+ - closures, promises, async/await, destructuring, modules, event loop, prototypes, error handling. Must understand asynchronous behaviour deeply, not just syntax

TypeScript - Typing components, props, API responses, generics, interfaces vs types. Missing from the original list - we should treat this as mandatory for all new projects

React.js - Functional components, hooks (useState, useEffect, useMemo, useCallback, useRef, custom hooks), component composition, lifting state, controlled forms, error boundaries, render performance

State management- Redux Toolkit, Zustand or Context API; plus React Query / TanStack Query for server state and caching

Node.js- Express or NestJS, middleware, routing, async patterns, streams, environment config, error handling, npm ecosystem, process management

API design- RESTful design, correct status codes, versioning, pagination, rate limiting, validation, clear error contracts





SQL & databases- PostgreSQL or MySQL - joins, indexes, transactions, normalisation, schema design, query optimisation, migrations, reading an execution plan

ORM- Prisma, TypeORM or Sequelize - plus knowing when to drop to raw SQL

HTML5 & CSS3- Semantic markup, Flexbox, Grid, responsive and mobile-first layout, cross-browser behaviour, basic accessibility (WCAG)

CSS frameworks- Tailwind CSS, Material UI, Bootstrap or styled-components

Authentication- JWT, refresh-token rotation, OAuth 2.0, session handling, role based access control, password hashing

Testing- Jest, React Testing Library; API tests with Supertest

Build tooling - Vite or Webpack, npm/yarn/pnpm, setting builds, bundlesize awareness

Disclaimer: This job posting has been aggregated from external source. Role details, content, and availability are subject to change. Applicants are advised to confirm the latest information directly on the company website before applying.

📌 Web Development Engineer (Mumbai)
🏢 E4 Software Services
📍 Mumbai