Conan is the clear winner today based on its 36+ GitHub contributors and the fact I found their Getting Started documentation to be easy enough to get working. It's MIT licensed too.
Conan's documentation even compares it to biicode which I was surprised wasn't mentioned in other answers, but biicode seems to be abandoned much like cpm.
pacm has some activity but is LGPL which may be an issue for some projects.
This builds on user3071643's answer, thanks!
