My server is a DiskStation, so I use HyperBackup to do an encrypted backup of the important data to their Synology C2 service every night.

Afaik this is not an error from Lemmy but from nginx, which is not able to relay the request to Lemmy and therefore returns a 502 bad gateway response. Imo this just means the servers are over capacity, so most likely a scaling/infrastructure issue.

I had a quick read of the code and it looks pretty solid to me. Not the most “enterprise” code imaginable, but definitely no code smell or quick hacking job.