Senior Frontend Engineer – React / Next.js

Senior Frontend Engineer — React / Next.js / AI

• Company: Celestial BI
• Employment Type: Full-Time
• Experience: 3+ Years
• Location: Sri Lanka / Remote
• Seniority: Senior

About Celestial BI

Celestial BI is building modern software products that combine cloud technologies, data, automation, and Artificial Intelligence to solve real-world business problems.

We are looking for a Senior Frontend Engineer who can take ownership of frontend development and build high-quality, scalable user experiences using modern React and Next.js technologies.

What You'll Do

• Design, develop, and maintain modern web applications using React.js and Next.js.
• Take ownership of frontend features from requirements through production release.
• Build reusable, scalable, and maintainable UI components.
• Integrate frontend applications with REST APIs and backend services.
• Implement responsive and user-friendly interfaces.
• Work with state management, routing, authentication, and API integrations.
• Optimize application performance and frontend architecture.
• Debug and resolve complex frontend issues.
• Participate in code reviews and technical discussions.
• Work closely with backend engineers, the project manager, and other team members.
• Use AI-powered development tools to improve development speed, code quality, testing, debugging, and documentation.
• Contribute to AI-powered product features and integrations where required.

Requirements

• 3+ years of professional frontend development experience.
• Strong experience with React.js.
• Strong experience with Next.js.
• Strong knowledge of JavaScript and/or TypeScript.
• Strong understanding of HTML, CSS, responsive design, and modern frontend development.
• Experience integrating REST APIs.
• Experience with Git and modern development workflows.
• Good understanding of frontend architecture and reusable component design.
• Ability to independently analyze problems and implement solutions.
• Strong debugging and problem-solving skills.
• Experience using AI development tools such as Cursor, Claude, ChatGPT, GitHub Copilot, or similar tools.

Nice to Have

• Next.js App Router.
• TypeScript.
• Tailwind CSS.
• React Query / TanStack Query.
• State management libraries.
• Experience with AI/LLM APIs.
• Experience building AI-powered applications.
• Automated testing.
• Docker and CI/CD.
• Cloud platforms such as AWS or Azure.

What We're Looking For

We are looking for someone who can own frontend development, not simply implement assigned UI tickets.

You should be comfortable:

• Making technical decisions.
• Understanding requirements and identifying gaps.
• Working independently.
• Reviewing and improving existing code.
• Learning new technologies quickly.
• Using AI tools effectively as part of your daily engineering workflow.