Shavarsh S.

Browser Extension Developer | Full Stack Developer | Javascript Dev

I am a TOP RATED PLUS Senior Full Stack Engineer with a strong focus on browser technologies, Chrome Extension - Plugin development, and scalable web applications. I have completed 22,000+ hours on Upwork with consistent 5-star reviews. My core expertise is building and maintaining Chrome, Edge, Firefox, and Safari extensions — including full lifecycle development from architecture to store submission. This includes Manifest V2 → V3 migrations, content scripts, background/service workers, messaging systems, DOM manipulation, automation flows, and integrations with tools like ChatGPT and other AI APIs. I also work on modifying and stabilizing existing extensions, improving performance, and ensuring compliance with browser store policies. From a full stack perspective, I design and build end-to-end systems using modern JavaScript and web technologies: * Frontend: React, Next.js, Vue.js, TypeScript, state management, SPA architecture * Backend: Node.js (Express/NestJS), REST APIs, GraphQL, authentication, webhooks * Data: PostgreSQL, MongoDB, Redis, data modeling and optimization * Realtime: WebSockets, event-driven systems * Integrations: third-party APIs, browser APIs, scraping/automation flows * DevOps: CI/CD, Docker, cloud deployments (AWS/GCP), monitoring I have built complex platforms across multiple domains, including marketplaces, SaaS products, CMS, CRM systems, browser automation tools, and internal business platforms. Many of these involve multi-user systems, dashboards, analytics, and high-performance backend logic. I also have experience with UI/UX implementation, product thinking, requirement specification, and working with partially generated or AI-assisted codebases — refactoring them into clean, production-ready systems. My focus is on building reliable, secure, and scalable solutions with strong attention to performance, maintainability, and real-world usability. Happy to discuss your project or jump on a call to go through the technical details. Profile updated: 08 September 2026