Use custom build wheel packages

[svartkanin]

Is there a way to add locally custom build wheel packages to the dependencies?

I have a 3rd party package that is not published to PyPi therefore installing it from there isn't an option.

[takluyver]

The usual way to do this is to specify --index-url or --extra-index-url to pip when installing the package (if you use --extra-index-url, you should be aware of the possibility of dependency confusion attacks, where someone uploads a package with the same name on PyPI).

There isn't really a good way to specify where a package should come from in the dependencies of a package itself. See this blog post on concrete vs abstract requirements for more background on why things work that way.