Immich is one of the only apps on iOS that properly does background sync. There is also PhotoSync which is notable for working properly with background sync. I'll take a wild guess that Ente may have got this working right too (at least I'd hope). This works around the limitation that iOS apps can't really run as background apps (appears to me that the app can wake up on some interval, run/sync for a little and try again on the next interval). This is much more usable then for example, the Synology apps for photo sync, which is, the last time I tried, for some reason insanely slow and the phone needs to have the app open and screen on for it fully sync.
Some issues I ran into is the Immich iOS app updating and then being incompatible with the older version of the server installed on my machine. You'd have to disable app updates for all apps, as iOS doesn't support disabling updates for individual apps.
In my specific scenario, the latest version of Immich for NixOS didn't perform a certain migration for my older version of Immich. I had to track down the specific commit that contained the version of Immich which had the migration, apply that, then I was able to get back to the latest version. Luckily, even though I probably applied a few versions before getting the right one, it didn't corrupt the Immich install.
That sounds about 100x more difficult to me
The problem was when I had to change some obscure .ini file in /etc for a dependency to something new I was setting up. Three days later I'd realise something unrelated had stopped working and then had to figure out which change in the last many days caused this
For me this is at least 100x more difficult than writing a Nix module, because I'm simply not good at documenting my changes in parallel with making them
For others this might not be a problem, so then an imperative solution might be the best choice
Having used Nix and NixOS for the past 6-7 years, I honestly can't imagine myself using anything than declarative configuration again - but again, it's just a good fit for me and how my mind works
I’m asking because you spoke to me when you said “because I'm simply not good at documenting my changes in parallel with making them”, and I want to understand if NixOS is something I should look into. There are all kinds of things like immich that I don’t use because I don’t want the personal tech debt of maintaining them.
I'm the beginning I was doing one change, writing that change down in some log, then doing another change (this I'll mess up in about five minutes)
Now I'm creating a new commit, writing a description for it to help myself remember what I'm doing and then changing the Nix code. I can then review everything I've changed on the system by doing a simple diff. If something breaks I can look at my commit history and see every change I've ever made
It does still have some overhead in terms of keeping a clean commut history. I occasionally get distracted by other issues while working and I'll have to split the changes into two different commits, but I can do that after I've checked everything works, so it becomes a step at the end where I can focus fully on it instead of yet another thing I need to keep track of mentally