Immutable in this context refers to an OS that can’t be changed while running. Steam deck does something like that. Basically the all of the OS system files are read only, so that the user or some malware can’t Bork the system. The only parts that are writable are the users profile directory and the logs.
You can still receive updates and install apps. It’s just that that’s handled a bit differently than with a standard OS.
E.g. it could be that the OS provider only issues complete updates, and then you either have to reboot. This is the case with steam os on the steam deck. The System portion of the OS is mounted read only during use.
I’m no expert on this but I’m pretty sure the /etc directory is writeable too for config files, which sadly still allows a user or malware to still bork the system if they get superuser privilege
I find it hard to imagine a system that is not borkable by a superuser. Maybe it’s helpful to think of immutable setups as harder to bork by accident during routine maintenance (e.g. through faulty updates) and more resilient to bad code (through containerization).
good point, that’s fair. The reason I think it bears mentioning is that editing configs under /etc/ is totally something we might expect a user to do. So you could follow a tutorial online that is wrong or outdated and with enough bad luck, tada, you bricked your “immutable” system. Or, less dramatic and more likely, something doesn’t work as intended anymore and you don’t know how to restore to the original config from when you installed.
Sounds proprietary.
An immutable OS is useful for things like an alarm clock, where if you accidentally muted the sound system, you could oversleep. There’s an obvious downside if you’re someone that watches porn on your alarm clock computer, but sometimes compromises must be made.
An OS that has reached perfection and doesn’t need changes anymore. Examples are Hannah Montana Linux, Temple OS, MS-DOS, Novell Netware.
You see, some operating systems are mostly operated by sound. If you mute them, they stop working. So it makes sense that you can’t mute them.