Senior Frontend Engineer (3D / WebGL)

About Harth

Harth is the AI-powered workspace for architecture. Architecture teams use it to model, visualise, render and collaborate in one browser-based tool, with nothing to install. In Harth you can bring in models from Revit, ArchiCAD, SketchUp and IFC, place them on real satellite terrain next to existing buildings, and produce renders with leading AI models. Teams work on the same scene together in real time and leave comments in 3D. Architects can keep working the way they already do. Harth just makes them faster.

The role

We're looking for a senior frontend engineer who loves both 3D on the web and polished product UI. You'll own much of the experience architects spend their day in: the 3D viewport, the tools around it, and the collaborative layer that ties it together. Performance, precision and feel all matter here, and you'll have real influence on the product and the technical direction.

What you'll do

• Build and improve Harth's browser-based 3D environment: scene management, navigation, selection, measurement and editing tools
• Make large architectural models (IFC, Revit, SketchUp and ArchiCAD imports) and terrain data load fast and render smoothly
• Build real-time multiplayer features such as presence, shared state and 3D-anchored comments
• Connect the viewport to Harth's AI rendering and multi-agent workflows so results feel instant
• Work closely with design, backend and AI engineers, and with the architects who use Harth every day
• Set the frontend standards for code quality, testing and performance, and mentor others on the team

What you'll bring

• 6+ years building production web apps, including several senior-level years with modern TypeScript and React (or similar)
• Deep, hands-on experience with 3D on the web, such as Three.js, React Three Fiber, Babylon.js or raw WebGL/WebGPU
• A solid grasp of 3D fundamentals: transforms, cameras, materials and shaders, picking/raycasting, LOD and instancing
• Experience profiling and tuning rendering and memory performance in the browser
• A product mindset and good taste in UI and interaction design
• Clear communication, and comfort working in a small team that moves fast

Nice to have

• Experience with BIM/CAD formats (IFC, glTF, etc.) or geospatial and terrain data
• Real-time collaboration tech such as CRDTs (Yjs, Automerge), WebSockets or WebRTC
• Writing custom shaders in GLSL or WGSL, e.g. post-processing, custom materials or compute
• A background in architecture, AEC, games or creative tools

Why Harth

• You'll shape a product that is changing how buildings get designed
• You'll be an early, senior hire with real ownership
• Competitive salary & benefits

How to apply

Send your CV or LinkedIn profile to [email protected], along with links to 3D work you're proud of, such as demos, repos or shipped products. A short note on why Harth interests you is a bonus.

Note we are an office first, with flexibility company, so you will need to be based in or willing to relocate to Christchurch for the role.