Develop and maintain scalable MERN web applications across frontend, backend, databases, testing, integrations, automation, AI/LLM features, and production deployment. Responsibilities include building React interfaces and Node.js services, optimizing MongoDB, implementing Playwright testing, creating n8n workflows, integrating APIs and payment systems, managing Git-based releases, debugging production issues, and collaborating with cross-functional teams. The role also includes technical mentorship and applying secure, performant, maintainable coding practices.
MERN Stack Developer
Summary
We are looking for a seasoned Full Stack Developer with specialized expertise in the MERN stack to spearhead the complete lifecycle of scalable web applications. This position requires a forward-thinking professional who can oversee everything from frontend and backend architecture to database tuning, automated testing, and live deployment. The successful candidate will bring specific knowledge in Playwright for testing, n8n for workflow automation, and hands-on experience embedding AI and Large Language Model (LLM) functionalities into software products. This role is central to fostering technical innovation, upholding high code standards, and working collaboratively across teams to produce high-performance, reliable solutions.
Location: Kolkata
Responsibilities
- Design, build, and sustain scalable web applications using the MERN stack, including the development of REST and GraphQL APIs.
- Create responsive and dynamic user interfaces leveraging React, JavaScript, TypeScript, HTML, and CSS.
- Develop resilient backend services and business logic utilizing Node.js and Express.js.
- Architect, refine, and administer MongoDB data models, covering schema design, query optimization, indexing, and aggregation pipelines.
- Enable smooth integration with external platforms by connecting third-party APIs, webhooks, and payment processing systems.
- Implement rigorous end-to-end and functional testing frameworks using Playwright.
- Create and manage business logic automation and API-driven workflows via n8n.
- Integrate AI and LLM APIs to enhance application features and streamline automated processes.
- Utilize AI-powered coding tools and prompt engineering strategies to boost development speed and code quality.
- Apply advanced understanding of LLM mechanics, including tokens, context windows, embeddings, RAG, and AI agent behaviors, to address complex technical challenges.
- Handle version control operations, including branching strategies, code reviews, pull requests, and release management through Git-based platforms.
- Direct deployment procedures, manage environment configurations, handle application publishing, and provide ongoing production support.
- Perform detailed debugging and root-cause analysis for issues affecting applications, APIs, databases, and live systems.
- Uphold industry standards for secure coding, performance optimization, and long-term code maintainability.
- Collaborate with QA, UI/UX, Product, and DevOps teams to ensure seamless feature delivery from initial concept to final launch.
- Offer technical mentorship and guidance to junior team members as needed.
Requirements
- Hold 4-7 years of professional experience in software development.
- Possess extensive, hands-on proficiency with the MERN stack (MongoDB, Express.js, React, and Node.js).
- Demonstrate mastery of React architecture, including hooks and state management, alongside Node.js/Express capabilities such as middleware, routing, and authentication.
- Show strong command over MongoDB schema design and the ability to build RESTful APIs while managing asynchronous JavaScript operations using Promises and async/await patterns.
- Exhibit solid frontend development skills using JavaScript, TypeScript, HTML, and CSS.
- Have a track record of implementing automated testing suites with Playwright.
- Demonstrate practical experience in building automation workflows, managing webhooks, and handling API integrations using n8n.
- Show familiarity with AI/LLM API integration, prompt engineering, and AI-assisted coding practices.
- Understand version control systems (Git/GitHub/GitLab), CI/CD pipelines, deployment strategies, and production environment management.
- Display strong problem-solving skills, a sense of ownership, effective communication abilities, and a dedication to maintaining high code quality.
Good to Have
- Experience with containerization using Docker and cloud deployment on platforms such as AWS.
- Knowledge of Redis, caching strategies, message queues (e.g., Bull/BullMQ), and techniques for performance optimization.
- Familiarity with Retrieval-Augmented Generation (RAG), vector databases, AI agents, or the development of AI-driven applications.
- A proven history of integrating OpenAI or other leading LLM platforms.
- Experience in creating complex automation workflows within n8n.
- Background in building applications using Next.js or other advanced React frameworks.
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