Feature Description

The nixpkgs team is heading towards a "perlless activation" direction where Perl should not exist in the base system by default.

This means replacing switch-to-configuration.pl implementation with a non-Perl language.

Ideally, this can be part of the nixos-cli tool itself, but this has to take into account a few things:

• Create a NixOS module which replaces the activation script that invokes switch-to-configuration.pl with a wrapper that runs nixos-cli's activation scripts.
• The behavior must be the same; no breaking changes can occur here between switch-to-configuration.pl and our implementation
• If ran directly, it must be ran in the context of the currently running generation
• In the future, remote activation using these scripts must be possible as well!

There is already a switch-to-configuration-ng written in Rust - use that as inspiration!

Let's create a new command called nixos activate that stores this functionality.

Command structure: (try to match switch-to-configuration.pl for now - come back later to this)

Goals:

• Use the new nixos activate interface when available to switch configurations
• switch-to-configuration.pl references still exist as a fallback mechanism for activation for older generations
• Be able to enable the perlless profile and still have a fully functioning NixOS system with nixos-cli

Help

Yes

Issues

• I have checked existing issues and there are no existing ones with the same request.