Senior Full-Stack Developer (Next.js / React.js)

We are seeking a full-time Full-Stack Developer with 4 to 5 years of professional experience in building and maintaining production web applications. The successful candidate will work on high-scale systems involving large volumes of data ingestion, third-party platform integrations, background processing, and complex data workflows. This role requires hands-on development of both frontend and backend components, ensuring reliability, scalability, and performance in a production environment.

Key Responsibilities

- Build, maintain, and scale production web applications using Next.js, React.js, and TypeScript.
- Design and implement robust backend APIs, services, and third-party integrations.
- Work extensively with Supabase and PostgreSQL, including schema design, indexing, query optimization, transactions, and performance tuning.
- Develop systems capable of handling high-volume incoming events and data from external platforms.
- Design and maintain asynchronous and background processing workflows.
- Implement authentication, authorization, row-level security, and other application-level security controls.
- Integrate and maintain third-party APIs and external services with reliability.
- Implement comprehensive error handling, retries, idempotency, rate-limit handling, and failure recovery mechanisms.
- Investigate and resolve production issues related to performance, databases, APIs, and application logic.
- Profile and optimize slow queries, API endpoints, background jobs, and frontend performance.
- Understand and safely modify existing production codebases without introducing regressions.
- Manage features through the full lifecycle: design, implementation, testing, deployment, and monitoring.
- Contribute to technical decisions regarding architecture, scalability, reliability, and maintainability.
- Write clean, maintainable, well-tested, production-ready code.
- Use Git/GitHub effectively for development, code review, and team collaboration.
- Utilize Claude Code and other AI-assisted development tools responsibly, independently reviewing, testing, and validating generated code.

Required Qualifications

- 4 to 5 years of professional software development experience.
- Strong fundamentals in JavaScript and TypeScript.
- Extensive practical experience with React.js and Next.js frameworks.
- Solid experience with PostgreSQL, including database schema design, indexing, query optimization, relationships, constraints, transactions, and performance troubleshooting.
- Practical production experience with Supabase.
- Strong understanding of REST APIs and third-party integrations.
- Experience working with high-volume data or event-driven systems.
- Knowledge of asynchronous processing, queues/background jobs, retries, and failure handling.
- Strong grasp of authentication, authorization, and database security principles.
- Proven ability to diagnose and resolve production performance and reliability issues.
- Ability to reason about scalability and identify technical bottlenecks.
- Excellent debugging and problem-solving skills.
- Ability to independently understand unfamiliar codebases and safely implement changes.
- Experience with Git/GitHub and collaborative development workflows.
- Capability to critically review, understand, debug, and validate AI-generated code rather than relying on it blindly.
- Good communication skills with the ability to clearly articulate technical decisions, issues, risks, and blockers.

Position Details

- Location: Johar Town, Lahore
- Work Type: Full-time
- Work Arrangement: On-site
- Start Date: Immediate
- Salary: Starting from Rs150,000 per month

Additional Information

Candidates should be able to reliably commute to or plan to relocate to Johar Town, Lahore before starting work. This is an in-person role requiring presence at the office.

This opportunity offers the chance to work on complex, high-impact systems with modern technologies in a collaborative environment focused on quality and scalability.