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# Senior Web Engineer II - Platform

- **Company:** AJAIB 495 LLC
- **Location:** United States (Remote available)
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** JavaScript (Programming Language), Application Programming Interfaces (APIs), Application Release Automation, Profiling, Code Review, Continuous Integration, E2e Testing, Next.js, Web Application Security, TypeScript, Management of Software Versions, Web Engineering, Web Usability, ReactJS, Backend, Material UI, Information Technology, Programming Languages
- **Published:** November 13, 2026
- **Apply:** https://arc.dev/remote-jobs/j/redirect/pyvyoac8v5

## About the Role

* Education: Bachelor's degree in Computer Science or equivalent practical experience
 * Experience: 5+ years of professional web engineering, including building shared libraries, design systems or tooling used by several teams
 * Languages & Frameworks: Strong in TypeScript and JavaScript; deep experience with React and a modern framework such as Next.js; strong component design
 * Architecture & Tooling: Experience with monorepos, bundlers, package publishing and build performance
 * Quality: Solid experience with unit, integration, visual and end-to-end testing, CI/CD and error monitoring
 * Performance & Security: Strong in browser performance profiling, accessibility and web security, including authentication on the web
 * Mindset: Ownership mindset, clear communication and a service attitude toward internal users. Experience in fintech or another regulated, high-traffic consumer product is a plus

## Description

As a Senior Web Engineer II in the Platform team, you build the web foundations that every Ajaib product team builds on: the design system and component library, shared packages, sign-in and session handling in the browser, and the build and release tooling. You own these foundations from design to production, treat other engineers as your customers, and help the engineers around you do better work.

 * Design, build and maintain shared web foundations: component library, design system, shared packages and the application shell
 * Own features end to end: technical design, implementation, testing, release and support for the teams that use them
 * Keep shared packages stable: clear APIs, semantic versioning, changelogs, migration guides and safe deprecation
 * Build accessible, themeable, well-documented components that product teams can adopt without custom work
 * Build and improve secure sign-in, session and token handling on the web, working with backend and Security teams
 * Improve build speed, CI/CD pipelines, monorepo tooling and release automation for all web teams
 * Set and measure performance budgets and quality standards, such as Core Web Vitals, bundle size and accessibility checks
 * Write maintainable, well-tested code and give thoughtful code reviews
 * Investigate production issues from error monitoring and feedback from product teams, and ship lasting fixes
 * Mentor mid-level engineers and share good web practices across teams