Solidsthataremadetobemade.
Forge is mechanical CAD on a from-source OpenCASCADE 7.9.3 kernel — true B-rep geometry, a real constraint solver, simulation, and drawings. The same Archie copilot that draws your part can also size it, simulate it, and detail it. Manufacturable, not just renderable.
Open source · free forever · public release soon · native B-rep, no WASM in the geometry path.
Native kernel
OpenCASCADE 7.9.3, compiled from source as forge-kernel.node. Real B-rep solids — no WASM in the geometry path.
Real constraints
A planegcs sketch solver with full degrees-of-freedom tracking — fully constrained means fully constrained.
Real scale
Organized assemblies past 100,000 components — packed into structure, not confetti.
Open stack
Open code and open model weights. Read it, self-host it, own it. No lock-in.
Native math · real solids · open source · runs on your machine.
A native B-rep kernel, compiled from source.
Most browser CAD tools run a kernel through a WASM shim and pay for it in precision and speed. Forge links OpenCASCADE 7.9.3 directly as a native Node addon — the geometry path is C++ all the way down.
True B-rep solids
Boundary-representation geometry with exact topology — faces, edges, vertices, and the relationships between them. Not meshes pretending to be solids.
NURBS surfacing
Sweeps, lofts, drafts, and variable-radius fillets on real surfaces, so curvature stays exact under edits.
Boolean reliability
Cuts, unions, and intersections resolved by a production kernel that ships in real engineering software.
Validated output
Every solid Archie produces passes a coherence gate — checkValidity() → valid — that verifies and repairs topology before you see it.
forge-kernel.node · native C++ · OCCT 7.9.3 · no WASM
The kernel binding is open — read exactly how every operation reaches OCCT.
Constraints that actually solve.
Forge sketches on the planegcs constraint solver — the same class of solver that drives professional parametric CAD. Add coincidence, tangency, equal, parallel, and dimensional constraints; the solver tracks degrees of freedom in real time and tells you exactly when a sketch is fully defined.
DOF readout
A live degrees-of-freedom counter — under-, fully-, or over-constrained, never a guess.
Geometric + dimensional
Coincident, tangent, parallel, equal, symmetric, plus driven and reference dimensions.
Archie speaks constraints
Ask for "two M6 holes 60 mm apart, symmetric about the centerline" and Archie emits the constrained sketch — fully defined, editable by hand after.
Focus the corner handle and use arrow keys to move it; Enter fully constrains the sketch. — watch the degrees of freedom fall to zero.
A hundred thousand components, organized.
Forge handles assemblies the size of a real facility — past 100,000 components — with real mates and live spatial queries. The zoned-facility generator lays them out the way a plant actually is: racks, drum farms, and machine rows packed into bays with aisles between them. Structure, not confetti.
components placed in a single organized facility
zoned bays · real mates · live spatial queries · stays responsive
Because the layout is structured, you can still select, query, and edit inside it — the assembly doesn't collapse into noise at scale. Archie can build the whole environment from one prompt and bound the camera to what matters.
The facility generator ships in the open — window.__forgeBuildEnvironment is yours to read and drive.
Real FEA, on the geometry you designed.
No export, no second tool. Forge runs finite-element analysis directly on the solids you build — and Archie can read the result and propose a fix.
- Linear-static
- Modal
- Thermal
- Buckling
- Fatigue
σ_vM · MIN → MAX · rendered as dot density, never color
Build a part, load it, read the stress field, change a dimension, re-solve — the same loop a real analyst runs, with Archie in the seat next to you.
The part leaves as something a shop can read.
A model that can't become a drawing or a toolpath is a render. Forge closes the loop: associative drawings with a title block, full GD&T, and CAM on the same B-rep solid.
Drawings + GD&T
Generate sectioned views with hatching, dimension them, and stamp feature-control frames — datums, position, profile, tolerances — straight onto the geometry. The drawing updates when the model does.
witness lines · ⌖ position · datums A·B·C · ±0.1 · title block
CAM
Drive toolpaths off the solid you designed, in the same kernel — no lossy round-trip to a separate CAM package.
toolpaths from B-rep · same kernel · no re-import
It moves both ways, losslessly.
Native STEP and IGES read and write means your model opens in SolidWorks, NX, Creo, and Fusion — and theirs opens in Forge — without a lossy re-import.
Because the geometry is real B-rep, a STEP export is a true solid a machinist can program against — not a tessellated approximation.
In and out · no lossy bridge · your model is portable, not trapped.
Describe the part. Read every move.
Archie drives Forge through structured, validated tool-calls into the real kernel — then hands back an editable feature tree, not a disposable script.
Reads like code, edits like CAD
Every operation Archie calls lands in the normal feature tree. Change the wall from 4 mm to 3 mm and the part re-solves locally — no second prompt.
Coherence gate
A validation pass verifies and repairs each solid before it reaches you — checkValidity() → valid.
Fully local, fully open
A DeepSeek-R1-distilled per-discipline model fleet runs on your machine. No cloud, no API keys, no per-token bill — and the weights are open. Your geometry never leaves the room.
Other text-to-CAD tools hand you disposable script. Archie hands you an editable feature tree the kernel already validated.
Open code. Open weights. Yours to run.
- Open code
- Read every line — the kernel, the app, the model harness.
- Open weights
- Archie's per-discipline fleet ships with weights you can run.
- Self-host
- Runs on your own machine. No cloud, no API keys, no lock-in.
- Public release soon
- Pre-release today — star the repo to follow the launch.
The questions a serious team asks.
- Kernel
- OpenCASCADE 7.9.3, compiled from source — native C++, no WASM (forge-kernel.node).
- Solids
- B-rep, NURBS surfacing, sweeps, lofts, drafts, variable fillets.
- Sketching
- planegcs constraint solver with full DOF tracking.
- Assemblies
- Up to 100,000+ components, real mates, live spatial queries.
- Simulation
- Linear-static, modal, thermal, buckling, fatigue — with contact.
- Manufacturing
- CAM toolpaths + associative drawings with full GD&T.
- Interop
- STEP, IGES, DXF, glTF, STL — read and write.
- AI
- Local DeepSeek-R1-distilled fleet, per-discipline fine-tunes, structured tool-calls.
- License
- Open source — open code and open model weights.
- Runs on
- Native Apple Silicon desktop app; Windows in progress.
- Cost
- Free forever to open; public release soon.
Real CAD. Forge is a from-source OpenCASCADE kernel with a constraint solver, FEA, CAM, and drawings. Archie drives it through validated tool-calls and hands back an editable feature tree — you can also drive every operation by hand.
Solids that are made to be made.
A from-source OpenCASCADE kernel, a real constraint solver, FEA, and drawings — all driven by Archie. Open source, on your machine.
Open source · free to start · public release soon