Hi Rene, Rene writes: > On the other hand, in linux there is `--system` argument, how does this > argument work?, Is there a script that uses it?. To test `--system`, I > removed it from my linux system and when loging in with my user it does not > detect any command. > > BOOT_IMAGE=/gnu/store/fiqgyafknihbvmz4j62ddb67p79kfcbk-linux-libre-4.19.13/bzImage --root=my-root --system=/var/guix/profiles/system-87-link --load=/var/guix/profiles/system-87-link/boot To see how the Linux kernel argument "--system" is used, check out the "boot-time-system" procedure in gnu/build/activation.scm. Ultimately this is used by the activation-service-type, defined in gnu/services.scm. In short, when the system boots, the activation service will atomically flip the "/run/current-system" symlink. and then run all the activation scripts defined by services that extend the activation service. The value of "--system" can be overridden by setting the GUIX_NEW_SYSTEM environment variable; in fact, we do that in the switch-to-system procedure in guix/scripts/system.scm, which is used when running commands like "guix system reconfigure", "guix system roll-back," and "guix system switch-generation". Hopefully that helps! -- Chris