Software Engineer, 3D Geometry & Computational Tools

Software Engineer, 3D Geometry & Computational Tools

About Lightmill

Lightmill is developing large-format laser milling: a new manufacturing process that scales laser milling from micron-scale features to much larger metal parts. Our goal is to make precision metal manufacturing more accessible, flexible, and affordable.

We are an early-stage startup, which means the work is broad, hands‑on, and high‑impact. Everyone on the team wears multiple hats, moves quickly, and helps build both the technology and the company around it.

We are looking for a software engineer who is excited to work at the intersection of 3D geometry, manufacturing, and high‑performance computation. This role is ideal for someone who has worked directly with 3D files, meshes, ray casting, spatial data structures, and geometry‑heavy software systems.

As a Software Engineer, you will be a foundational contributor to the brains of the laser mill, the software that turns digital part geometry into manufacturable laser milling operations. The work spans computational geometry over high‑resolution meshes, real‑time GPU and graphics programming, and combinatorial optimization across a vast configuration space. In practice, that means working across 3D representations, geometric algorithms, machining strategy, ray casting and simulation, and the analysis tools that sit on top of them.

This is a hands‑on engineering role for someone who enjoys solving hard geometric problems and building robust software that interfaces with the physical world.

• Build and maintain software for processing 3D geometry, including meshes, solids, surfaces, and point‑based representations.
• Work with common 3D and manufacturing file formats such as STL, OBJ, STEP, 3MF, or similar.
• Develop algorithms involving ray casting, ray‑mesh intersection, spatial indexing, visibility analysis, collision detection, and geometric queries.
• Help convert part geometry into manufacturing instructions, simulations, or toolpaths.
• Build internal tools for visualizing, debugging, and validating 3D geometry and process outputs.
• Collaborate closely with mechanical, manufacturing, and controls engineers to connect software outputs to real‑world machine behavior.
• Improve performance, reliability, and numerical robustness of geometry‑processing pipelines.
• Design software systems that are clear, maintainable, and testable despite complex geometric edge cases.

• Strong software engineering fundamentals and experience building production‑quality systems.
• Practical experience working with 3D geometry, meshes, CAD files, or spatial data.
• Experience with GPU‑native development, ray casting, spatial indexing, or related geometric algorithms.
• Familiarity with computational geometry and graphics programming concepts such as BVHs, octrees, compute shaders, and rasterization.
• Comfort working in Python, C++, Rust, or similar languages used for performance‑sensitive geometry or simulation work.
• Ability to debug complex numerical, geometric, and coordinate‑system issues.
• Interest in manufacturing, robotics, simulation, CAD/CAM, graphics, or physical systems.

• BS degree in Computer Science or equivalent experience.
• 4+ years of hands‑on experience

• Experience with CAD/CAM software, toolpath generation, CNC, additive manufacturing, robotics, or industrial automation.
• Familiarity with libraries such as Open CASCADE, CGAL, trimesh, meshlib, VTK, Open3D, Embree, PyVista, or similar.
• Experience building 3D visualization tools using OpenGL, WebGL, Three.js, Unity, Blender, or custom viewers.
• Experience with GPU acceleration, parallel computation, or high‑performance geometric algorithms.
• Knowledge of manufacturing constraints, metrology, machine calibration, or process simulation.
• Experience working in a startup or fast‑moving hardware environment.

• You have built software that reads, transforms, analyzes, or visualizes 3D geometry.
• You enjoy debugging why a ray missed a triangle, why a mesh is non‑manifold, or why a coordinate transform is slightly wrong.
• You care about correctness, robustness, and performance.
• You are excited by software…