Home Manager currently installs packages into the user environment,
precisely as if the packages were installed through
nix-env --install
. This means that you will get a collision error if
your Home Manager configuration attempts to install a package that you
already have installed manually, that is, packages that shows up when
you run nix-env --query
.
For example, imagine you have the hello
package installed in your
environment
$ nix-env --query
hello-2.10
and your Home Manager configuration contains
home.packages = [ pkgs.hello ];
Then attempting to switch to this configuration will result in an error similar to
$ home-manager switch
these derivations will be built:
/nix/store/xg69wsnd1rp8xgs9qfsjal017nf0ldhm-home-manager-path.drv
[…]
Activating installPackages
replacing old ‘home-manager-path’
installing ‘home-manager-path’
building path(s) ‘/nix/store/b5c0asjz9f06l52l9812w6k39ifr49jj-user-environment’
Wide character in die at /nix/store/64jc9gd2rkbgdb4yjx3nrgc91bpjj5ky-buildenv.pl line 79.
collision between ‘/nix/store/fmwa4axzghz11cnln5absh31nbhs9lq1-home-manager-path/bin/hello’ and ‘/nix/store/c2wyl8b9p4afivpcz8jplc9kis8rj36d-hello-2.10/bin/hello’; use ‘nix-env --set-flag priority NUMBER PKGNAME’ to change the priority of one of the conflicting packages
builder for ‘/nix/store/b37x3s7pzxbasfqhaca5dqbf3pjjw0ip-user-environment.drv’ failed with exit code 2
error: build of ‘/nix/store/b37x3s7pzxbasfqhaca5dqbf3pjjw0ip-user-environment.drv’ failed
The solution is typically to uninstall the package from the
environment using nix-env --uninstall
and reattempt the Home Manager
generation switch.
Home Manager is only able to set session variables automatically if it manages your Bash or Z shell configuration. If you don't want to let Home Manager manage your shell then you will have to manually source the
~/.nix-profile/etc/profile.d/hm-session-vars.sh
file in an appropriate way. In Bash and Z shell this can be done by adding
. "$HOME/.nix-profile/etc/profile.d/hm-session-vars.sh"
to your .profile
and .zshrc
files, respectively. The
hm-session-vars.sh
file should work in most Bourne-like shells.