I hit annoyances when using sqlite when dealing with some corner-cases. I wanted to implement a lock and share some small amount of data (who did what when) between two different linux users on the same machine.

I figured "sqlite is better than fopen, let's use that!", but between directory permissions, all the WAL files, probably the sqlite3 python lib and Diskcache (https://pypi.org/project/diskcache/) not helping things, it was a real pain, where regularly under different race conditions, we would get permission denied errors. I managed to paper it over with retries on each side, but I still wonder if there was a missing option or setting I should have used.