* Spike: typed parameter contracts and JSON Schemas for solid.box and solid.extrude The schema RFC's spike (plan/schema-spike.md). solid.box and solid.extrude get typed contracts with generated JSON Schemas (2020-12), checked in front of the unchanged handlers by a per-session level: off (the default, which changes nothing), warn (the call runs and gains param_warnings) or strict (the call is refused and the design left alone). Also engine.describe and the MCP tool describe_command, `solidcraft-cli mcp --param-check off|warn|strict`, a FeatureResult type for feature replies, and an env-var audit recorder (SOLIDCRAFT_PARAM_AUDIT) used to check the contracts against every test. Local spike branch; not for upstream as is (see the results report). Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * Parameter contracts: put the audit recorder behind a feature; drop two ignored test keys The audit recorder is now on only in a build with the engine's `param-audit` feature and `SOLIDCRAFT_PARAM_AUDIT` set. Its code is still compiled, linted and tested without the feature. `scripts/param_audit.py` summarises a test run's audit logs, and the schema module's docs give the steps for converting a further command. Two tests passed keys their command ignores, which the audit found: `position` on `solid.box` (`hole_face_tests.rs`) and `symmetric` on `solid.extrude` (`face_tests.rs`). Both are removed, so the tests build what they always did. Comments no longer call the contracts a spike. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> --------- Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com> Co-authored-by: bherbruck <brennen.herbruck@gmail.com>
SolidCraft
An open-source parametric 3D CAD application built in pure Rust.
Sketch, constrain, and build solids with a parametric feature timeline. Change a dimension
and watch your model rebuild. Run it on your desktop, in your browser, or let AI agents
model through the built-in MCP server.
Website ·
Download ·
Try it in the browser ·
Documentation ·
Discord ·
SolidCore
A Raspberry Pi 4 case from an empty design: a sketch dimensioned with the board's parameters, extrude, fillet, shell, the rim rounded in one pick, an M2.5 standoff patterned on the 58 × 49 mm hole rectangle, port cut-outs, vent slots, "Pi 4" engraved in DejaVu Sans Bold and a PETG material defined in the design, with its mass in Properties, then height 24 → 32 mm in Parameters and it all rebuilds. 9× playback. Full video, recorded with the demo script.
Download
- Windows: the installer, or
winget install bherbruck.SolidCraft. - macOS: the disk image (Apple silicon and Intel).
- Linux: the AppImage, or
sudo snap install solidcraft(Snap Store). - Web: try it in your browser, no install.
ARM64 and 32-bit builds, portable zip, .deb, .rpm, Flatpak and the other packages are on the downloads page. The downloads aren't signed yet: on Windows choose More info, then Run anyway in SmartScreen; on macOS right-click SolidCraft and choose Open the first time. On SolidCraft 0.11 to 0.14, download once by hand; see updating.
What works
Early but usable for simple parts: 75 of 76 public reference parts match their analytic or FreeCAD-computed volume, area, centre of mass and bounding box (oracle); the other is a tracked bug.
- Sketches and constraints: lines, arcs, splines, text and more, solved by our own constraint solver, with parameter-driven dimensions.
- Features: extrude, revolve, sweep, loft, fillet, chamfer, shell, draft, holes, threads, patterns, mirror, split and combine on an editable parametric timeline.
- Parameters and configurations with unit-aware expressions.
- Assemblies with joints, motion studies, contact sets, interference and mass properties.
- Sheet metal with flanges, hems, fold/unfold and flat patterns, and plastic enclosure features.
- Files: STEP, IGES, 3MF, STL, OBJ and glTF in and out where supported, URDF export,
.solidcraftdesigns. - Desktop app, browser app, headless CLI and MCP server, all running the same commands.
The full list is in docs/capabilities.md and docs/features.md; status and plans are in ROADMAP.md. See also what people built, 3D mouse support and the architecture.
Build from source
cargo run --release -p solidcraft -- --sample # desktop app with a sample part
cargo run --release -p solidcraft-cli -- commands # the command registry
cargo run --release -p solidcraft-cli -- run examples/bracket.json --out bracket.step
cargo xtask ci # fmt, clippy, tests, icons, assets, layers, wasm
More commands, the Windows cross-build and the browser build are in docs/building.md.
AI agents (MCP)
solidcraft-cli mcp is a Model Context Protocol server. Headless it
runs its own design session, or with --connect it drives the running app so you can watch.
Claude Code: claude mcp add solidcraft -- solidcraft-cli mcp. Tools, access rules and an
example session: docs/mcp.md.
Scripts
A script is a JSON list of the same commands the UI runs, executed with solidcraft-cli run.
Format and example: docs/scripts.md. Pages can also be driven through the
browser command API.
Contributing
Help is welcome. CONTRIBUTING.md covers how to build and test, the code map, the clean-room and licence rules, and where help is wanted most. Open work is in GitHub issues; chat is on Discord.
Sponsors
SolidCraft's continuous integration runs on Blacksmith, which sponsors its CI minutes.
Licence
MIT OR Apache-2.0, at your option. Developed under the clean-room contribution rules; third-party code and assets retain their documented licences and attribution.
SolidCraft is independent. Behaviour is designed from public documentation, general CAD conventions and user feedback. Reference tests use analytic values and open-source tools. SolidCraft is not affiliated with, sponsored by or endorsed by Autodesk, Dassault Systèmes, PTC, Siemens or any other CAD vendor. Fusion, AutoCAD, Inventor, SolidWorks, Onshape, Creo, Blender and Tinkercad are trademarks of their respective owners, named only to describe compatibility (see NOTICE).

