I had a bunch of personal scripts to manage my music database. Maybe 10-sh scripts, max a few hundred lines long, nothing too big. A little while ago, I wrapped them into a big emacs org file for literate programming, and to tangle them, so I could easily edit them in one place. Backed them up to at least three servers, both locally and in another building. I also have Cronopete running, (a Linux implementation of MacOS Time Machine), so everything is safe, right? Right?!. I didn’t need the scripts for 3 months or so, but today I wanted to use them but couldn’t find them anywhere. Not on any backup server, not on the Cronopete drive. The only thing I can think of is that I must have saved that org file on the backup server and then backed up over it (and it never got pulled by Cronopete because it does of course not look at the backup server). I will have to start rewriting those scripts from scratch. FML.
On a side note, w.r.t. keeping the dependencies up to date, have a look at renovatebot. It creates merge request for each and every dependency update, thus triggering a build to check that everything is OK.