Slight bump in the road: the Gramps package requires several packages that require C code to be compiled, as well system packages to be installed. That’s not a end user hurdle I am willing to add to Betty (especially considering the current situation allows for the loading of Gramps data without additional dependencies). Would it be possible (in a near future release) to be able to install Gramps’ APIs without being forced to install all dependencies that are not prebuilt for different platforms? For example, cairo is unneeded in my case, as Betty does not need Gramps to manipulate graphics.
E.g. considering Gramps 6 is not (fully) stable yet, one option would be to make all of these packages optional dependencies. That way someone running pip install gramps would only get the Gramps code and dependencies for which cross-platform builds exist (or that are pure Python), and if they want full service they must instead run pip install gramps[cairo] for cairo support (and then manually take care of the additional system requirements).