It’s not. Imagine Immich required library X to be at Y version, but another service on the server requires it to be at Z version. That will be a PitA to maintain, not to mention that getting a service to run at all can be difficult due to a multitude of reasons in which your system is different from the one where it was developed so it might just not work because it makes certain assumptions about where certain stuff will be or what APIs are available.

Docker eliminates all of those issues because it’s a reproducible environment, so if it runs on one system it runs on another. There’s a lot of value in that, and I’m not sure which resource you think is being wasted, but docker is almost seamless without not much overhead, where you won’t feel it even on a raspberry pi zero.

The main “wasted” resources here is storage space and maybe a bit of RAM, actual runtime overhead is very limited. It turns out, storage and RAM are some of the cheapest resources on a machine, and you probably won’t notice the extra storage or RAM usage.

VMs are heavy, Docker containers are very light. You get most of the benefits of a VM with containers, without paying as high of a resource cost.

If it were actual VMs, it would be a huge waste of resources. That’s really the purpose of containers. It’s functionally similar to running a separate VM specific to every application, except you’re not actually virtualizing an entire system like you are with a VM. Containers are actually very lightweight. So much so, that if you have 10 apps that all require database backends, it’s common practice to just run 10 separate database containers.

Docker has very little overhead

On the contrary. It relies on the premise of segregating binaries, config and data. But since it is only running one app, then it is a bare minimum version of it. Most containers systems include elements that also deduplicate common required binaries. So, the containers are usually very small and efficient. While a traditional system’s libraries could balloon to dozens of gigabytes, pieces of which are only used at a time by different software. Containers can be made headless and barebones very easily. Cutting the fat, and leaving only the most essential libraries. Fitting in very tiny and underpowered hardware applications without losing functionality or performance.

Don’t be afraid of it, it’s like Lego but for software.

No because docker is not actually a VM

I’ve had immich running in a VM as a snap distribution for almost a year now and the experience has been leaps and bounds easier than maintaining my own immich docker container. There have been so many breaking changes over the few years I’ve used it that it was just a headache. This snap version has been 100% hands off “it just works”.

https://snapcraft.io/immich-distribution