Senior Full Stack Web Developer – Mission-Critical System Integration

Keystone Digital

Part-time · Remote · Flexible hours

About the role

Keystone Digital is revamping the performance and reliability of its customer‑facing services. We need a Full Stack Web Developer to redesign critical front‑end and back‑end components, ensuring fast load times and robust uptime.

Key responsibilities

• Audit existing React UI for bottlenecks and implement lazy loading, code splitting, and caching strategies.
• Refactor NodeJS services to improve response latency, add rate limiting, and enhance error handling.
• Design and optimize MongoDB queries, introduce indexing, and monitor performance metrics.
• Write unit and integration tests, and set up CI pipelines for automated quality checks.
• Collaborate with QA and product teams to prioritize reliability fixes.

Must-have skills

• Strong experience with React and modern JavaScript (ES6+).
• Proficient in NodeJS server development and RESTful API design.
• Solid understanding of MongoDB schema design and performance tuning.
• Ability to work independently in a remote, part‑time schedule.

Nice to have

• Familiarity with Docker containers.
• Experience with performance monitoring tools (e.g., New Relic, Datadog).