Updates
Layup checks for a new release daily, and Server > Updates shows it. Update downloads it, checks its signature, backs up Layup's database on the server, and restarts. Apps keep running throughout.
Every release is signed. A server installs only releases signed with Layup's release key, whichever address it downloads them from.
Mirrors
Releases are plain files, so any web server or bucket can mirror them: latest.json, latest.json.sig, install, and a folder per version. Install from a mirror, and update from it afterwards, with --feed: