As an example closer to home (and more relevant to the Linux packaging debate), a lot of Mastodon instances are potentially going to have index corruption when glibc updates. Server admins will have to pay close attention during their next `sudo apt-get update` and make sure to reindex Postgres right afterwards, or else hashtag links might be broken. https://docs.joinmastodon.org/admin/troubleshooting/index-corruption/
I would much prefer Postgres to just bundle/static-link glibc, but I guess that's not how they do things.
As a software developer, it's unlikely your CI is testing every possible environment. Nor should you be expected to test the combinatorial explosion of every OS/browser/bundler/framework/other factors that could affect compatibility.
That's why I really like GitHub's approach with Dependabot. It opens a PR to update a dependency, and shows you *what percentage of all repos had broken CI tests due to this update*. This spreads out the CI testing cost. It's brilliant. https://dependabot.com/
#Smithereen update. Groups are more-or-less done, as a proof of concept. They should federate in theory, but I haven't tested any of it yet because I'm too lazy to set up a second internet-facing instance and Mastodon isn't very much compatible with what I'm doing here.
That said, there's still a lot of work ahead. Admin/moderator features, public admin list, events, invitations...
Mammut (https://github.com/jamiesanson/Mammut) is a new Android client. The interface is pretty good, the notifications support are not ready yet.
Subway Tooter (https://github.com/tateisu/SubwayTooter) is one of more feature rich clients for Android, but the interface don't follow Twitter's paradigm so most people say it's "hard to use".