About the job:

At Kothar, we’re building the tools scientists and engineers will use in the next era of computing. That means designing a custom programming language, building a next-generation IDE, and creating the backend systems that power them.We’re looking for a Senior Front-End Developer who can tackle complex web challenges and help us deliver a world-class experience through our custom IDE and scientific computing platform. You’ll work closely with our compiler, physics, and API teams to create powerful, responsive, and elegant interfaces that make scientific computing intuitive and accessible.This role combines deep front-end craft with systems-level complexity - ideal for someone who loves building fast, interactive, and technically sophisticated web applications.

Why join us? At Kothar, you’ll:

• Build a custom web IDE that redefines how scientists and engineers code, visualize, and run computations.
• Work with modern React, TypeScript, and web rendering frameworks to build real-time, multi-pane interfaces.
• Tackle advanced UI problems: editor integration, live job status, data visualizations, and more.
• Collaborate directly with experts in compilers, HPC, and runtime systems.
• Shape a product that sits at the intersection of developer tools, science, and performance computing.

What you’ll do:

• Design and build advanced user interfaces in React and TypeScript for our custom IDE.
• Implement features such as interactive code editors, visual debugging tools, dynamic data visualizations, and physics simulations.
• Integrate with language tooling (LSP), backend APIs, and live execution systems.
• Optimize rendering performance, responsiveness, and user experience across complex layouts.
• Collaborate with designers and backend engineers to shape the product’s interaction model and architecture.
• Help define and evolve our front-end best practices, component libraries, and development workflows.

What we’re looking for:

• Strong expertise in React, TypeScript, and modern web development.
• Experience building complex, interactive, high-performance web apps (e.g. IDEs, dashboards, design tools, or data-heavy UIs).
• Deep understanding of web performance, concurrency (e.g. React Suspense, workers), and rendering pipelines.
• Familiarity with web-based editors (e.g. Monaco, CodeMirror) or developer tooling is a plus.
• Ability to work collaboratively across design, backend, and compiler teams.
• Excitement to create something new - not just another web app, but a new kind of scientific computing environment.

Bonus points:

• Experience integrating LSP or language tooling in web environments.
• Knowledge of web-based streaming architectures (SSE, WebSocket).
• UI/UX sensitivity with attention to polish and accessibility.
• Background or interest in scientific computing, visualization, or developer tools.