SolidCraft: Open-Source Parametric CAD, From GitHub to Your First Part

SolidCraft CAD is parametric modelling in the SolidWorks tradition: you draw a sketch, dimension it, constrain it, then build solids on a feature timeline that rebuilds when a parameter changes. The difference is the stack underneath. SolidCraft is written entirely in Rust, renders through a GPU compositor, and compiles to WebAssembly so the same editor runs in a browser tab.

The SolidCraft workflow is the familiar four steps the project puts on its own site: sketch, build, refine, exchange. Sketches live on origin planes, offset planes or planar faces and support lines, rectangles, circles, arcs, polygons, slots, ellipses, splines and text. Features include extrude, revolve, sweep, loft, fillet and chamfer, shell, draft, holes, threads, patterns, mirrored copies, split and combine. Every feature is editable, and the timeline rebuilds incrementally rather than from scratch.

Two details make SolidCraft CAD more than a demo. The constraint solver is the project’s own, not a wrapper around a commercial kernel, and the B-rep kernel is the open-source truck boundary representation. Those choices are why the app can be MIT or Apache-2.0 and still export real STEP files. In a market where parametric CAD is usually rented by the month, that is the whole pitch.

The SolidCraft GitHub repository is github.com/tangency-labs/solidcraft. When we looked on Oct 18, 2026 it showed 4.7k stars, 560 forks and 33 releases, with 659 open issues and an active pull-request queue. The licence is MIT or Apache-2.0 at your option, developed under clean-room contribution rules, which matters if you plan to vendor it into a product.

The move to Tangency Labs is recent, and any older SolidCraft GitHub link you saved is worth re-checking. Release notes for v0.15.0 say SolidCraft now lives at tangency-labs/solidcraft and that old links redirect, but versions 0.14.0 and older have an in-app update check that does not follow the move. If you are on an older build, download 0.15.0 by hand once; from that version on, the update check follows the new home.

The SolidCraft GitHub repository is also where the roadmap lives. The README is unusually candid: it lists what works, points at the roadmap for known limitations, and publishes an attribution file for third-party components. If you are evaluating SolidCraft for a team, read the issues first. The volume is high, and it tells you more about maturity than the star count does.

The SolidCraft download is published on the SolidCraft GitHub releases page, with the latest stable v0.15.0 and nightly builds beside it. Windows gets an MSI plus a portable zip, for x64, arm64 and x86, and a winget package: winget install bherbruck.SolidCraft. macOS gets one universal DMG for Apple silicon and Intel. Linux gets an AppImage, deb, rpm, Flatpak and Snap, with arm64 builds for the ARM machines that need them.

The installers are not signed yet, and the README says so plainly. On Windows, SmartScreen will warn you and the path is More info, then Run anyway. On macOS, the first launch needs a right-click and Open rather than a double-click. That is ordinary for a young open-source project, and it is still a real friction point for a managed machine where you cannot click through a warning.

Every SolidCraft release ships SHA256SUMS.txt, so the SolidCraft download can be checked before it runs. If you are installing the SolidCraft desktop build on a work laptop, check the hash and keep the file with your software inventory. A checksum does not make an unsigned build safe in the way a notarised one is, but it does prove the bytes are the bytes the SolidCraft repository published.

SolidCraft runs in a browser at solidcraft.io/app, no install and no account. The build is the same Rust application compiled to WebAssembly, which means the sketch tools, the timeline and the STEP export are the same code paths as the desktop app rather than a cut-down viewer. It is the fastest way to find out whether the modelling model suits you.

The SolidCraft browser build is also the honest demo: open a design, drag a dimension, watch the timeline rebuild. On a laptop with a decent GPU the interaction is close to native, and on an older machine the first load is the slow part, because the WebAssembly bundle has to arrive before anything renders. Give it a few seconds on the first visit and keep the tab open afterwards.

Two limits are worth stating. A browser tab cannot read and write your local files the way a desktop app can, so anything you want to keep should be exported rather than left in the session. And the desktop build remains the one with installers, the CLI and file associations. Use the browser for a trial, the desktop for a project.

The SolidCraft feature list is broader than the version number suggests. Sketches support construction geometry, projection, trimming, fillets and chamfers, and the constraint solver handles the usual geometric and dimensional set. Parameters accept unit-aware expressions such as 2 * width + 5 mm, and configurations let one design carry several variants without duplicating the file.

Export is where SolidCraft CAD punches above its weight. STEP is written as AP242 with body names, colours and components as assemblies, and revolved faces come out as native planes, cylinders, cones, spheres and tori rather than tessellated approximations. IGES 5.3, 3MF, binary and ASCII STL, OBJ, glTF and a current-view DXF export sit beside it, and assemblies with joints can be written as URDF for robot simulators. Import covers STEP AP203, AP214 and AP242, IGES, and mesh formats.

The reference SolidCraft project on the repository is a Raspberry Pi 4 case built from an empty design: a dimensioned sketch, extrude, fillet, shell, a patterned standoff, port cut-outs, vent slots and engraved text, all on the timeline. That is a real part with real constraints, not a cube with a hole. It is the best single answer to “what can SolidCraft actually do” that the project publishes.

SolidCraft vs Fusion 360 is not a fair fight on breadth, and it is not a fair fight on price either. Fusion 360 brings cloud collaboration, versioning, CAM, simulation, drawings and a decade of tutorials and plugins. SolidCraft brings a free licence, a local file, a browser build and an MCP server, and it stops well before manufacturing toolpaths.

The SolidCraft vs Fusion 360 table under this heading marks only what the two projects document. Where Fusion 360 has a capability SolidCraft does not ship, the row is a miss rather than a “coming soon”. Where SolidCraft is genuinely different — the licence, the local-first file, the agent interface — the row is a win. Read it as a map of which job each tool is for, not as a scoreboard.

The practical split for SolidCraft vs Fusion 360 is simple. If your work ends at a STEP file that someone else machines, SolidCraft covers the modelling and exports cleanly. If your work continues into toolpaths, simulation studies, drawing sets and a colleague reviewing the file in a browser, Fusion 360 is still the shorter path today. A hobbyist, a student or a workshop that owns its files can start with SolidCraft and lose very little. If your work is 2D drafting rather than parametric solids, the CADCraft guide covers the AutoCAD-shaped tool instead. For the full head-to-head on licence, files and CAM, read SolidCraft vs Fusion 360.

SolidCraft ships a SolidCraft MCP server, solidcraft-cli mcp, and the SolidCraft MCP interface is not a gimmick bolted on the side. Every action in the app is a command, so the same command registry that drives the interface drives the agent interface. An agent can create a sketch, set a parameter, measure a body, take a screenshot and export a STEP file inside the running app or headless.

The project’s own demonstration is a rover called SELENE, built entirely through the SolidCraft MCP server: 3,323 editable timeline steps that rebuild with no errors. That is the interesting claim. It is not that an agent can draw a shape, it is that the result is a parametric design a human can still edit, rather than a mesh blob with no history.

If you are evaluating SolidCraft MCP for automation, this is the feature that separates SolidCraft from every other free CAD app. The tool calls are scoped to the open design’s folder when it sits inside your home directory, which is a sensible guard rail rather than a sandbox. Read the MCP documentation before you point an agent at a folder of client files.

The first SolidCraft limit is scope. SolidCraft is a modeller: sketches, features, assemblies and exchange formats. It is not a CAM package, not a simulation suite and not a drawing office. If your deliverable is a dimensioned drawing sheet or a toolpath, you will finish elsewhere, and that is a product decision rather than a bug waiting to be fixed.

The second SolidCraft limit is maturity. The download is unsigned, the release cadence includes nightly builds, and 659 open issues is a lot of surface area. The app is stable enough for the workflow in its own demo, and it is not the tool to bet a production deadline on without a test part of your own. Keep the design file and export early.

The third SolidCraft limit is ecosystem. Fusion 360 has plugins, tutorials and a hiring pool; SolidCraft has a README, a docs site, a Discord and an MCP server. That is enough to learn the tool, and it is not enough to replace a team’s shared workflow this month. The honest summary is a strong second tool that can become a first tool for the right kind of work.