As mentioned, packages can be installed directly from our conda channel. You may however want to build your own package at some point in the future or you may want to fix some of ours by submitting a Pull Request on github (You are more welcome to do so...)
This is a companion discussion topic for the original entry at https://www.underworldcode.org/articles/build-conda-packages/
I don’t really understand the build / host separation in your description or in the conda documentation.
Conda does all its builds in an isolated environment so you do need to specify everything explicitly including pip if you need it because whatever you have locally does not count. Can you give an example of something extra that is needed for the host and what should be in the build section v. the host section ?