maddler That’s correct. But there’s no real Docker, nor Docker Desktop, for the Mac. Making a true Mac version of Docker would have meant containerizing the Mac environment with packages, plists, etc, and would have little to no value, as no existing Docker projects would work on it. Docker opted for a different approach on the Mac: a resource-intensive and buggy application that instead launches a VM with linux in it every time Docker Desktop is run. Everything is done inside this VM (I assume something similar happens on Windows).
The first DD Mac came out during the x86 days and (I believe) was virtualized. Post ARM transition, I’m not sure if DD Mac was emulating or virtualizing, or a mix, with a base ARM build for M-chip Macs and a fallback to the system x86 emulation layer (Rosetta) for any packages not available for ARM. But the performance has always been abysmal, and the app extremely buggy, and the upshot was that any Mac user wanting to use Docker would surely want to run their own linux in a VM, with tools like VMWare, UTM, etc, or with Apple’s own virtualization framework (for this, Tart VM is very good).
In the past few years, things seem to have changed a bit, as just about everything seems to be available in an arm64 build, and these newer Docker Mac GUI tools have emerged. I haven’t played with OrbStack too much but from what I can see, it is just a highly optimized, transparent VM, coupled with a native mac binary executable that passes commands to the VM, and a clean Swift UI app to manage running containers (sort of like Portainer). There are also a lot of out-of-the-box tweaks regarding reverse proxy for local domain names that seem to be more oriented around running a couple apps locally with ease rather than setting up a public webserver.
I’m a little hazy on the details of what kind of virtualized environment this thing uses, and so was curious if there are other Mac sysadmins about there working with Mailcow, and if anybody had tried anything other than Docker in a full VM. So far I’ve had it running happily in a Ubuntu Server VM for several months (and am liking the arm virtualized performance, snapshots and easy migrateability this approach offers) and so I suppose I should just answer my own question and give it a shot. In case anyone is interested, I’ll report back. The performance optimizations and native app are seductive but maybe not worth the effort (and drawbacks in those other areas).
Meanwhile, a true thanks to everyone who has contributed to making Mailcow such a mature and robust product. Thanks!