Sr. Software Development Engineer (React/Typescript/Browser Extension Development)

🏢 About Zscaler

Zscaler runs a cloud-native Zero Trust security platform, connecting users, devices, and applications securely across any location. The Frontend Engineering team here builds directly inside the browser, not just around it.

🎯 The Role

Join the team building Zero Trust Browser, a Browser Detection and Response (BDR) extension that protects users inside Chrome, Firefox, and Safari. This goes beyond typical UI work — you'll write TypeScript that detects threats, enforces enterprise policy, and analyzes content in real time across the extension's execution contexts, running on millions of browsers without degrading performance.

🛠️ Tech Stack

• React (or similar reactive framework) + TypeScript
• Browser extension APIs, MV2/MV3 manifest models
• HTML5, CSS3
• Build tooling: esbuild, Vite, Rollup, or Webpack

💼 What You'll Do

• Translate product and UI/UX requirements into browser-extension features, from user-facing UI to in-browser security logic
• Implement security-sensitive code that runs on every page load with minimal latency and memory footprint
• Write comprehensive unit and integration tests; debug across background scripts, content scripts, popups, and extension pages
• Collaborate closely with UI/UX, backend, and QA to ship features end-to-end

✅ What You'll Need

• 2-4 years building production frontend applications in TypeScript/JavaScript
• Browser-extension development experience (Chrome, Firefox, and/or Safari), with working knowledge of extension APIs and MV2/MV3 permission models
• Strong ES6+ JavaScript and TypeScript fundamentals
• Experience with React, Vue, or Svelte
• Proficient in HTML5 and CSS3, including responsive component-based UI

🌟 Nice to Have

• Experience publishing to a browser extension store, or building across Chromium/Gecko/WebKit
• Familiarity with modern build tooling and pipeline optimization
• Basic web security knowledge (XSS, CSRF, content isolation) and Node.js exposure for tooling