hackerscad — parts you write, see and print

hackerscad is a parametric CAD where the model is code. Type and the 3D view follows; round an edge with the mouse and the code is written for you. Exact solids, real threads, files for every printer.

Downloadall systemsMake your first part

Linux, Windows and macOS · free and open source

Using an AI coding assistant?

Paste this to it: it installs hackerscad's skill, then hackerscad itself if it's missing (asking you first) and the MCP server. Then it reads the language from docs written for agents, checks and renders its models, and shows them in your window. More below

Install the hackerscad skill for all my projects from https://raw.githubusercontent.com/trikko/hackerscad/main/docs/SKILL.md, with https://raw.githubusercontent.com/trikko/hackerscad/main/docs/llms-full.txt next to it, then follow its "Setup and updates" section.

1 · write

Code is the model

A small, sandboxed language with units, selectors and libraries. It diffs, versions and reviews like any other code.

2 · click

The mouse writes code

Fillets, holes, sketches on a face, parts moved and patterned: every click lands in the file, readable.

3 · print

Send it to the printer

3MF with a colour per part, STL, STEP, or a drawing with views and dimensions.

// batteries.hcad: a holder for AA cells
import std;

@param immutable cells = 4;
immutable aa = 14.5.mm, play = 0.4.mm;
immutable hole = aa + play, pitch = hole + 2.mm;

@part
Solid holder()
{
    auto b = box(cells * pitch + 2.mm,
            pitch + 2.mm, 22.mm)
        .fillet(edges.parallel(Z), r: 3.mm);

    // a pocket for each cell, its rim chamfered
    foreach (i; 0 .. cells)
        b -= cylinder(d: hole, h: 22.mm)
            .move(x: (i - (cells - 1) / 2.0) * pitch,
                z: 3.mm);
    b = b.chamfer(edges.of(faces.top), d: 0.6.mm);

    // a grip on both long sides, last
    return b
        .knurl(faces.front, kind: "diagonal",
            pitch: 3.mm)
        .knurl(faces.back, kind: "diagonal",
            pitch: 3.mm);
}

// a cell in the first pocket, to see it fit
@part("Yellow Pop", alpha: 0.4, export: false)
Solid cell()
{
    auto body = cylinder(d: aa, h: 49.5.mm);
    auto tip = cylinder(d: 5.5.mm, h: 1.mm)
        .move(z: 49.5.mm);
    return (body + tip)
        .move(x: -(cells - 1) / 2.0 * pitch, z: 3.mm);
}

unittest
{
    assert(hole > aa, "an AA cell does not fit");
    assert((holder & cell).volume < 0.01.mm ^^ 3,
        "the cell rubs against the holder");
}

Exact solidsOpenCascade B-rep: fillets, shells, sweeps, lofts and real threads.

Safe to openA C-style scripting language, familiar from C, Java or JavaScript, in a sandbox: no files, no network. Any model is safe to open.

A real editorCompletion, hover help and constrained sketches you edit with a click.