Delta or incremental updates on pacman

Idea proposal 💡

Checks

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Summary

In order to reduce band usage for mirror servers you may use an incremental/delta update.

Motivation

Less used band, more happy server owners.

Specification

Maybe using rsync, idk, or checking the installed files for differences, like flatpak does Another take on the issue may be the use of p2p updates, where the pacman's cache is shared on a bit-torrent-like protocol ready for being used.