Grid:space

From https://grid.space/about.html

GRID:SPACE is exploring the concepts of modular, reusable building blocks for human habitation. An short-term goal is to enable the design and creation of adaptable structures that can outlive their initial purpose or limitations. As new concepts are proven, they will be posted on Thingiverse and linked here.

there are a few projects, including a slicer, a block editor, where "unit blocks" can be meshes, (i.e. full-cube, corner, edge) and construction systems.