- Open-source CAD debate: participants question whether designers could be constrained to pure F-rep or CSG without losing essential capabilities, and whether exposing underlying topological representations directly to users could replace the “grab-bag of modeling tricks” found in commercial kernels like Parasolid.

- Machining-tolerance problem: GD&T (geometric dimensioning & tolerancing) is hard to encode without B-Rep because tolerances are properties of topological entities; current research explores annotating implicits, but machine-readable specification remains awkward.

- B-Rep critique: current boundary representations cheat by approximating surface intersections, leaving hidden gaps and requiring complex rules to manage discretization errors—illustrated by the surprising complexity of describing a simple cylindrical hole in a flat plate (linked paper: https://repositories.lib.utexas.edu/items/6b18d003-9da7-429e-b01d-b3b12220f8c0).

- Voxel-based machining simulation proposed: store tool-paths and recompute final shape at arbitrary resolution instead of storing geometry, forcing designers to choose physically plausible tools; counter-argument notes voxels poorly approximate lathe operations and high-performance cams where higher-order derivatives matter.

- Existing voxel-CAD tools mentioned: juri__’s open-source CSG voxel project and commercial 3D-Coat (https://3dcoat.com) cited as the most advanced voxel modeler.

- Legal datapoint: federal judge ruled Anthropic’s use of books to train Claude is fair use under U.S. copyright law (with the caveat that pirated books are excluded).

- New research shared: “Flow-Lenia: Emergent evolutionary dynamics in mass-conservative continuous cellular automata” (arXiv 2506.08569) introduces a system for simulating multi-species environments where rule-sets compete for mass, with demo video at https://x.com/eplantec/status/1937569852698308806.