# Senior Software Engineer, Frontend

**Company:** [Zoo](https://hotfix.jobs/companies/zoo)
**Location:** Remote
**Role:** Frontend Engineering
**Salary:** $145k – $195k/yr
**Skills:** TypeScript, React, Xstate, JavaScript, Webassembly, Codemirror, Ast, Rust, Webgl, Browser Internals
**Posted:** 2026-04-29

> Senior Frontend Engineer develops and optimizes a CAD modeling app's UI using TypeScript, React, and XState. Integrates with WebAssembly, CodeMirror for code-to-3D model bridging, and focuses on high performance and browser optimization.

## Job Description

## What You’ll Do

- Develop and optimize the frontend of our modeling app, focusing on performance and user experience
- Collaborate with backend teams to design and implement robust APIs that support the app's code-driven design functionality
- Enhance the app's UI/UX by leveraging Typescript, React, and XState, ensuring that the interface is both powerful and easy to use
- Develop delightful CodeMirror extensions that bridge the gap between the user's code and the 3d-model
- Implement advanced AST/code-mods, CodeMirror enhancements, and deep integration with WebAssembly (Wasm) for performance improvements
- Utilize Xstate for state management to maintain app consistency and reliability across various user interactions
- Apply a deep understanding of JavaScript and browser internals to improve app functionality and performance

## What You’ll Need

- B.S. in Computer Science or a related field, or equivalent professional experience
- Substantial experience in frontend software development building complex, highly performant and scalable applications
- Strong proficiency in Typescript and React, with a portfolio or examples of complex applications built using these technologies
- Deep knowledge of JavaScript and its internal workings and performance optimization techniques
- Familiarity with WebAssembly (Wasm) and its use in web applications for performance enhancements
- Understanding of browser internals across major browsers (Chrome, Firefox, Chromium, Brave, etc.) and their impact on application performance and compatibility
- Knowledge of Xstate or similar state management libraries

## Nice to Have

- Proficiency with Rust
- Experience with CodeMirror6
- Experience with ASTs even if custom ESLint rules
- Experience with WebGL or web graphics
- A background in geometry and/or experience with design-based software

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**Apply:** https://hotfix.jobs/jobs/96073950-2d17-443f-9989-94df5eb12141
**Canonical:** https://hotfix.jobs/jobs/96073950-2d17-443f-9989-94df5eb12141