Incorporate new system metaphor more broadly
The metaphor used to be "recipe" and cooking, which is a little precious (and has been used by other build systems, besides). The metaphor now is construction -- since we talk about building software this might be a more apt metaphor, and is certainly no worse than cooking.
What other terms fall out of this? Does the metaphor provide better names for "package" or "commands"? (In building construction, is there a term for installing all the trim and furnishings? That would be what "commands" does.)
For pre-fab buildings, is there a term for the components that are taken to the construction site and connected to each other? That would be a good term for thematically-related components (e.g. the cross-toolchain section). I would tend to call these "modules," except that Module is already a heavily-used term in computing (and is a thing in Ruby, besides) so it would be confusing rather than clarifying. "Assembly" is also a frequently-used term, I think -- doesn't .NET refer to libraries as "assemblies"? We'll just call them "Sections" (mixing metaphors a bit, since that's a nod to the literate side of Litbuild) until we think of a better name.
If litbuild needs to invoke other commands to do things (e.g. run shell scripts or something), this could "subcontracting"?