Precision tools for a program that was built for clay.
Three add-ons for Blender: a real CAD kernel with exact B-rep solids, a directable retopology engine, and a hard-surface sculpting kit that finishes in clean quads. All three are feature-complete and release-tested against Blender 5.1 and 5.2. None has been published yet — this page is the work itself.
A real CAD kernel inside Blender. Exact trimmed surfaces, watertight booleans, true fillets — and STEP back out.

Blender's mesh tools are built for organic shapes; precise, manufacturable parts fight you at every step. NURBS Forge brings OpenCASCADE — the kernel behind FreeCAD and a number of commercial CAD packages — into Blender as a bundled wheel.
The model is an exact B-rep solid, not a mesh approximation. What you see in the viewport is only a display tessellation, re-derived from the real geometry and stored inside the .blend. That distinction is what makes watertight booleans, true variable-radius fillets and lossless STEP round-tripping possible.




Point at an eye socket. Get eye topology. Every other auto-retopo tool gives you one button and one opinion.

Run Auto Retopo on a sculpt, a 3D scan or an AI-generated mesh and get a clean all-quad base. Then select just the region that matters — an eye, a mouth, a limb, a joint, a crease — and rebuild only that, with the topology an artist would lay by hand, stitched back in with zero T-junctions. Everything else stays untouched.
The retopology engine is written in Rust and ships inside the extension. No Python packages, no external binaries, no setup step.




The whole mechanical workflow on one tab, so you stay in Sculpt Mode from blockout to retopo.

Hard-surface sculpting in Blender means fighting the brushes. Everything is tuned for clay, cuts are a trip to Edit Mode, and greebles are a second add-on.
This one cuts like a vector tool: draw a Bézier path on the surface with 0/45/90° guides and a live angle readout, then cut straight through. An open path is a guillotine blade; a closed shape is a cookie cutter. Every boolean seam gets a Sharp, Chamfer or Round edge applied only to the cut, never to the rest of the model.




Tessera's Rust retopology engine and NURBS Forge's modelling core each carry their own suite, run headless on every change before anything reaches the add-on layer.
254 engine · 196 core testsEach add-on registers in a real Blender, drives its operators against real geometry, inspects the result and unregisters cleanly — on Blender 5.1 and 5.2 LTS.
NURBS Forge 811 · Hard Surface 46 checks · Tessera 8 harnessesThe built zip is installed into a throwaway Blender profile and exercised there. Tessera's gate also asks the bundled engine whether it accepts every option the add-on sends, so a stale engine cannot ship.
run before every uploadEvery file in a rebuilt zip is compared against the source before upload. The check exists because a package built three minutes before a bug fix carried the same filename and version number, without the fix.
Hard Surface Sculpt 1.6.1: 22 / 22 filesGPL-3.0-or-later with full source. Bundled components — OpenCASCADE (LGPL-2.1), cadquery-ocp (Apache-2.0), VTK (BSD-3) — ship with their licence texts, and Tessera carries third-party notices for its bundled engine.
perpetual updates across each 1.x seriesParts of this code were generated with an AI coding assistant, then reviewed, edited and integrated manually. No runtime cloud AI: Tessera's optional assist runs a model on the user's own machine.
stated on every listing