Installing Firefox is a good example for a package that could be
installed as a user, since it is a graphical one.
Also use thunderbird as a second example.
Since 03eaa48 added perl.withPackages, there is a canonical way to
create a perl interpreter from a list of libraries, for use in script
shebangs or generic build inputs. This method is declarative (what we
are doing is clear), produces short shebangs[1] and needs not to wrap
existing scripts.
Unfortunately there are a few exceptions that I've found:
1. Scripts that are calling perl with the -T switch. This makes perl
ignore PERL5LIB, which is what perl.withPackages is using to inform
the interpreter of the library paths.
2. Perl packages that depends on libraries in their own path. This
is not possible because perl.withPackages works at build time. The
workaround is to add `-I $out/${perl.libPrefix}` to the shebang.
In all other cases I propose to switch to perl.withPackages.
[1]: https://lwn.net/Articles/779997/
This option can be set to disable installer tools like nixos-rebuild,
nixos-install, and nixos-generate-config (as well as more). This is
nice when a system is not expected to be rebuild or reconfigure itself
such as in a stateless PXE setup, as well as other embedded scenarios.
Note, that the system can still be updated, but it must either get
nixos-rebuild from another source, or, for embedded systems, be
upgraded by another machine like:
nix copy "$system" --to "ssh://root@<host>" && ssh "root@<host>"
"nix-env -p /nix/var/nix/profiles/system --set $system && $system/bin/switch-to-configuration switch".
Along with other options, this allows removing Perl from a closure.
For example:
{
boot.enableContainers = false;
environment.defaultPackages = [];
system.disableInstallerTools = true;
}
should not include Perl.
The only nix version available in the installer should be the version
configure in the module system. If someone needs `nixUnstable` in their
`nixos-install` they should probably set the module option and not just
add it to the closure.
Also add --all, which shows the value of all options. Diffing the --all
output on either side of contemplated changes is a lovely way to better
understand what's going on inside nixos.
This sets networking.useDHCP to false and for all interfaces found the
per-interface useDHCP to true. This replicates the current default
behaviour and prepares for the switch to networkd.
cross-compilation of `btrfs-tools` is broken, and this usually needless dependency of each system closure on `btrfs-tools` prevents cross-compilation of whole system closures
