Drafter

Drafter is a small parametric modeller that runs in the browser. I started it to design some cabinets after moving, but the tools work in terms of sketches, faces, and solids.

The geometry is deliberately limited: horizontal and vertical lines, right angles, and lengths stored as whole sixteenths of an inch. Sketch a shape, extrude it, then draw on a face of what you’ve built. Named measurements and expressions let dimensions depend on each other. Change a material thickness once and the parts using it update together.

Ableton was the reference for the UI: flat panels, compact controls, and a layout that stays consistent as you work. Colour marks selection and active tools. Labels appear when you need them, rather than covering the drawing by default. I built a small component library on React Aria, with shared colour tokens and Storybook to work on the controls in isolation.

Documents stay in the browser and can be saved as JSON files. Drawing sheets turn the model into scaled pages with dimensions and notes, something I can hand to the person building it.

I used OpenSpec to work through the behaviour before implementing it with agents.

Try Drafter, or read how the cabinet project started.