Senior Full Stack Developer (MERN)

Innovation Insight, a PSEB-registered IT services company based in Lahore, specializes in software development, AI integration, and platform engineering for international clients in fintech, edtech, and ecommerce sectors. Our engineers develop and maintain real production systems including payment platforms, AI-powered applications, and high-traffic consumer products, working closely with global stakeholders. We are seeking a Senior Full Stack Developer capable of independently managing end-to-end feature development—from database schema design to deployed user interfaces—across diverse client projects. The role requires expertise in the MERN stack, enhanced with NestJS and Next.js, and a commitment to delivering production-quality code with efficient third-party integrations and AI-assisted development workflows.

Key Responsibilities
- Develop and maintain full-stack features using Next.js/React on the frontend and NestJS/Node.js on the backend across multiple client projects.
- Integrate payment gateways such as Stripe and PayPal, along with other third-party APIs, ensuring robust error handling, logging, and test coverage.
- Conduct thorough code reviews for mid-level and junior engineers, promoting high-quality standards and best practices.
- Participate actively in architecture and technical design discussions, contributing to or producing technical specifications before implementation.
- Own deployment and monitoring of features, ensuring stability and performance in production environments.
- Proactively identify and report technical debt, security vulnerabilities, and performance bottlenecks.
- Maintain clear and comprehensive documentation for APIs, integration workflows, and environment configurations.

Required Qualifications
- Proficiency in NestJS, Next.js, Node.js, and React.js, with the ability to architect new modules independently.
- Strong understanding of REST API design and GraphQL, including schema design, resolvers, subscriptions, and federation.
- Hands-on experience with microservices architecture, including service decomposition, inter-service communication (REST, gRPC, message queues), and distributed state management.
- Expertise in MongoDB schema design, Mongoose, and aggregation pipelines.
- Commitment to writing clean, maintainable code with proper separation of concerns and disciplined Git version control practices.
- Experience integrating international payment gateways (Stripe Connect, webhooks, payouts, disputes; PayPal) and understanding payment lifecycles and compliance.
- Skilled in third-party API integration, including OAuth2/JWT authentication, rate limiting, error handling, and retry strategies.
- Proficiency with Docker (Dockerfiles, docker-compose), CI/CD pipelines (GitHub Actions, AWS CodeDeploy, or equivalent), and AWS fundamentals (EC2, S3, RDS/DocumentDB, IAM).
- Knowledge of Nginx configuration for reverse proxy and SSL termination, and process management tools like PM2 for Node.js applications.
- Active use of AI development tools (GitHub Copilot, Cursor AI, Claude, ChatGPT, Builder.io) with practical experience integrating AI features such as LLM APIs, embedding-based search, recommendation engines, or conversational interfaces.
- Strong problem-solving skills, capable of debugging complex issues across frontend, backend, and infrastructure layers, and comfortable working with ambiguous requirements.
- Excellent communication skills in English, with experience collaborating in Agile/Scrum teams and working closely with international clients.

Preferred Qualifications and Benefits
- Experience with TypeScript across the full stack, including strict typing in NestJS and Next.js.
- Familiarity with Redis for caching, session management, or pub/sub.
- Exposure to real-time technologies such as WebSockets or Server-Sent Events.
- Knowledge of relational databases like PostgreSQL alongside MongoDB.
- Prior experience working with clients in North American or European time zones.
- Contributions to open-source projects or a public portfolio showcasing delivered work.

This is an onsite role based in Lahore. We expect senior-level judgment, including accurate estimation, timely delivery, proactive communication of blockers, and mentoring of junior engineers. Candidates should be comfortable transforming rough product requirements into clean, deployed features without needing detailed specifications.

Work Location: In person