The Tectonic Typesetting System — The Tectonic Typesetting System probably does a better job explaining how it works that I do. From my experience so far any style files are runtime downloads and get cached in a user directory, this happens when you compile a .tex file, there’s no “manager” visible, it gets done automatically. I guess you could force it to download styles at install by triggering a build of some .tex file.
Here’s a log from travis today of a Tectonic.jl run: Travis CI - Test and Deploy with Confidence. Scroll down and you’ll see an example of what happens on the first run of tectonic.
Probably, not tried yet though.
Apparently from https://dataverse.org/ according to their website.