Senior 3D Engineer

Role Overview

You will build the 3D heart of Moon's platform - real-time 3D in React Three Fiber and Three.js that homeowners experience in their own homes. This is a role for an engineer who loves both the craft of real-time 3D and the discipline of building for other engineers: new capabilities shipped as clean abstractions, and performance treated as a feature with a number on it.

• You will join a small, senior team with a mandate to build boldly. The 3D experience is used by designers selling in customers' homes - it runs on tablets, in the field, in front of homeowners - so everything you build is measured in frames, megabytes, and seconds to first render. You will own hard, high-leverage optimization problems whose specifics we share during the interview process.

• Develop new 3D capabilities that serve multiple product teams - exposed as clean, versioned, documented APIs rather than one-off features.
• Own render and runtime performance on real devices: frame rates, load times, and memory budgets on tablets in customers' homes - profile, fix, and hold the budgets.
• Own the optimization of our core 3D data formats and structures - significant size reduction is a priority, and you will design the formats, pipelines, and loading strategies that get us there (specifics shared under NDA).
• Do deep scene-graph work: materials, geometry, lighting, instancing, and data-driven scene assembly.
• Write the documentation and examples that make your work consumable without meetings; support consuming teams on a light rotation.
• Ship daily behind flags with AI-assisted workflows on a shared design system.

• 5+ years of front-end/graphics engineering with production Three.js or React Three Fiber.
• Strong 3D fundamentals: scene graphs, materials, lighting, geometry, GPU performance - and the linear algebra beneath them.
• Real experience optimizing data formats, asset pipelines, or file sizes (compression, binary formats, lazy loading, LODs) - you can tell a before/after story with numbers.
• Profiling depth across GPU, CPU, and memory; you find the actual bottleneck, not the assumed one.
• Experience building libraries or SDKs consumed by other teams a strong plus.
• Pragmatic, detail-oriented, and fast-moving.