The KapyCAD blog

Engineering posts

Everything filed under Engineering. 11 posts.

EngineeringOct 8, 2026

kapycode: your model as text

In KapyCAD 2 every document will have a readable text form, kapycode, and you'll be able to go from the text to the editor and back without losing anything.

SSergioRead post
Engineering12 min

Which of your constraints is redundant?

From "your sketch is wrong" to "these two dimensions contradict each other". KapyCAD 2 will flag redundant or clashing constraints, and only after checking.

S@sergioOct 6, 2026
Engineering8 min

Dragging without the sketch jumping

You drag a point and the sketch rearranges itself or flips over. In KapyCAD 2, dragging will follow four intent rules and nothing will jump when you let go.

S@sergioOct 2, 2026
Engineering11 min

Why we wrote our own constraint solver

Drags that take over a second and dimensions that flip a segment: why KapyCAD 2 will have a sketch solver of its own.

S@sergioSep 30, 2026
Engineering9 min

A Rust core for the whole document

In KapyCAD 2 the whole document will live in a core written in Rust, in a single worker next to the kernel. The interface will only ask and draw.

S@sergioSep 26, 2026
Engineering11 min

Our own OpenCascade

KapyCAD 2 will rebuild our OpenCascade 8.0 without emulated exceptions and, in our measurements, regenerate with less than half the CPU.

S@sergioSep 23, 2026
Engineering9 min

Update without fear: your files open exactly as you left them

KapyCAD's file format has changed some fifty times over these months of development, and a chain of pure steps keeps your parts opening unchanged.

S@sergioSep 19, 2026
Engineering11 min

How do you test CAD software?

In CAD software, the worst bug is one that moves a face 0.2 mm without throwing an error. These are the layers of tests that hunt for it.

S@sergioSep 16, 2026
Engineering3 min

Naming faces is hard: stable topological references

Why a fillet on a boolean can break a reference, and how KapyCAD keeps it alive across a regen.

S@sergioJun 19, 2026
Engineering3 min

How we solve your sketches: the 2D constraint solver

What a constraint solver is, and how it turns "these sides are equal" into geometry that adjusts itself.

S@sergioJun 18, 2026
Engineering4 min

A B-Rep CAD in the browser: OpenCascade, WASM and two WebWorkers

How KapyCAD runs a real CAD kernel inside a tab, without freezing the interface.

S@sergioJun 16, 2026
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