> unless you've done something very clever like 1 package per layer I struggle to think that 50 is really useful?
1 package per layer can actually be quite nice, since it means that any package updates will only affect that layer, meaning that downloading container updates will use much less network bandwidth. This is nice for things like bootc [0] that are deployed on the "edge", but less useful for things deployed in a well-connected server farm.
It doesn't work this way really?
It's called a layer because each layer on top depends on the layers below.
If you change the package defined in the bottom most layer, all 49 above it are invalid and need re-pulled or re-built.
Yes, my intended meaning was that if you're doing that or something similar then I totally get having lots of layers because it's useful. Mostly I've only seen it come up with nix, but I can see how bootc would have a similar deal. That said, most container images I've ever seen aren't doing anything that clever and probably should be like... 2-3 layers? (One base layer, one with all your dependencies shoved in, and maybe one on top for the actual application.)