I have written multiple small libraries to be used with my current and future projects. They are too small and interdependent for a github project each, and I would like to keep them together (in one git repo).

I also use some official Arduino libs.

If I set USER_LIB_PATH to the directory containing my libraries, the project does not see the official libs in my sketch directory. USER_LIB path does not seem to accept ':' or ' ' as a separator.

I could use symlinks, but I do not want to clutter neither my library nor the libraries dir in my sketch directory.

Probably I could go with a git submodule, but I do not know how to structure an Arduino project into multiple folders, and if it is even possible?

Or can I make one lib with multiple modules, and cherry-pick what I use (what is compiled into the hex file) from them in the actual project?