Sr Full Stack Developer
KopiustechUnited States • Cambridge, Massachusetts, United States
Posted December 17, 2025
Full Time
About the Company
Kopius is a technology company that values individuals who embody our core values: Community and Connection, Exceptional Experiences, Embrace New Ideas, Ownership Mentality, and Walk the Talk.
Job Description
We are looking for a Senior Full-Stack Software Engineer to build modern, scalable web applications using React, Next.js, JavaScript/TypeScript, and Java/Spring Boot. In this role, you will contribute across the full stack—delivering high-quality user interfaces, building resilient backend services, and collaborating closely with product, UX, and engineering teams to implement reliable, performant solutions in a fast-paced, highly regulated environment.
Requirements
- Build and maintain web pages and full-stack applications using React, Next.js, JavaScript, TypeScript, Java, and Spring Boot.
- Implement responsive, modern user interfaces using Tailwind CSS.
- Collaborate with UX designers and translate Figma designs into pixel-accurate, accessible UI components.
- Design, develop, and integrate REST and GraphQL APIs.
- Build and maintain WebSocket-based services for real-time data interactions.
- Deploy and optimize front-end applications on Cloudflare Pages or similar edge-optimized platforms.
- Write clean, maintainable, and performant code with comprehensive unit and integration tests.
- Translate complex business and technical requirements into actionable engineering solutions.
- Collaborate with cross-functional teams to ensure accurate implementation and timely delivery.
- Continuously evaluate tools, frameworks, and processes to improve performance, reliability, and developer experience.