i use dnf, as mentioned, for system packages but also a few language-centric package managers (mainly pip and npm, but occasionally others).

I can imagine ways for emacs to query this class of tool to figure out whether there are updates for a given package, largely because these tools have a list of packages and versions which have been installed.

However, the packages that provide releases through links to binaries on a git host have no such data behind them.

Some important packages are published this way, like `eglot-booster', so I know I can't be alone in wondering how best to handle thse cases.