The video on Containerization.framework, and the Container tool, is live [0].
It looks like each container will run in its own VM, that will boot into a custom, lightweight init called vminitd that is written in Swift. No information on what Linux kernel they're using, or whether these VMs are going to be ARM only or also Intel, but I haven't really dug in yet [1].
If you search the code, they support Rosetta, which means an ARM Linux kernel running x86 container userspace with Rosetta translation. Linux kernel can be told to use a helper to translate code using non-native architecture.
It looks like each container will run in its own VM, that will boot into a custom, lightweight init called vminitd that is written in Swift. No information on what Linux kernel they're using, or whether these VMs are going to be ARM only or also Intel, but I haven't really dug in yet [1].
[0] https://developer.apple.com/videos/play/wwdc2025/346
[1] https://github.com/apple/containerization