I might have accidentally forked live-wrapper.
I sometimes need to build Debian live iso images for work, and some time ago got into an inconvenient situation in which live-wrapper required software not available in Debian anymore, and there was no obvious replacement for it, so I forked it and tried to forward-port things and fill the gaps.
Over time this kind of grew: I ported it to python3, removed difficult dependencies, added several new features that I needed, and removed several that I didn't need.
I recently had a chance to document the result, which makes it good enough to be announced, so here it is. The README has an introduction and links to documentation, recipes and examples.
I'm not actively maintaining this except when work requires, so if there's anything extra you need for it, the best way to get it is via a merge request.
I'm not sure how much of live-wrapper is still left in the fork. If anyone starts using it, we should probably look into a new name.