In Stibium, models are functional representations: pure math describing, for every point in space, how far inside or outside the shape it is. You build them in a node graph: boxes wired to boxes, every parameter live, every node a small Python script you can open and edit. There are no meshes until the moment you export one, so nothing ever gets approximated, degenerate, or non-manifold while you work.
It is a continuation of Antimony by Matt Keeter, itself a spiritual successor to kokopelli by way of fabserver.
Antimony went into maintenance mode in 2016. Stibium picks the project back up and keeps going. Since the fork:
Geometry in, geometry out
- Mesh import: drop an STL (scan, vendor part, old export) into the graph and it becomes a solid distance field like everything else: subtract it, blend it, lattice it, re-export it. Sign comes from winding numbers, so imperfect scans still work.
- Fidget import:
stibium model.vm --import-vm out.sbtranslates math tapes from Keeter's successor project Fidget into Stibium projects. - Modern export: 3MF (typically 6× smaller than STL), SVG and DXF vector output with sharp-corner recovery for laser cutting and photolithography, and error-bounded mesh simplification. Meshing and rendering run on all cores.
A deeper modeling vocabulary
- O(1) domain repetition: infinite arrays, polar rings, mirrored tilings, and self-similar scale recursion at constant cost (the classic Array nodes union N copies and weep).
- Parts library: provably-mating ISO threads, involute gears, printable clearance holes with M2–M12 tables, dovetails, snap clips, hex vents, heat-set bosses.
- Smooth (log-sum-exp) and quadratic blends, chamfers and fillets, exact-distance primitives, gyroid lattices, bends and twirls.
Quality of life
- Cross-section preview, analytics overlay, recent files, export dialogs that suggest sane resolutions and show real dimensions, a canvas that stays smooth on 300-node graphs, and a seven-year backlog of crash fixes cleared.
The full ledger is in CHANGELOG.md.
Build from source (Linux and Mac).
Open an example to get oriented: examples/showcase_gear.sb is a
lightened involute gear built the way a user would build it, and
examples/import_bead.sb shows a scanned mesh being drilled by an
f-rep cylinder.
- USAGE.md - the tour
- SCRIPTING.md - writing your own nodes
If you hit an issue or have a question, open an issue.
For Antimony history and design rationale, see Matt Keeter's writeup.
Stibium's new work is released under the GNU Affero General Public License v3.0 or later (AGPL-3.0-or-later).
© 2022-2026 Nate Dube
Code inherited from Antimony remains under its original MIT License, and every third-party work Stibium redistributes (vendored libraries, bundled fonts) is accounted for in THIRD_PARTY_LICENSES.md. Algorithmic lineage and debts are credited in ATTRIBUTIONS.md.
© 2013-2022 Matthew Keeter and other contributors (Antimony)
Antimony includes code from kokopelli, which is © 2012-2013 Massachusetts Institute of Technology © 2013 Matthew Keeter