Cheatsheet: Difference between revisions

!|NixOS (system-wide and root)

!|NixOS (user) and Nix in general

|-

| colspan="5" style="text-align:center"| Basic concepts

|This column will let you do everything you can with Ubuntu and more.

|This column just isn't possible in Ubuntu.

|-

|Who can install packages and who can run them?

|Packages root installs are system-wide. It does so through through /etc/nixos/configuration.nix. If root installs packages the same way users do, through ~/.nixpkgs/config.nix, they are also global. Root's default profile is the system-wide default profile.

|Users can install their own packages and have their own profiles (environments) through ~/.nixpkgs/config.nix

|-

|Package manager

|nix, but many system-wide operations are provided by nixos packages.

|Just nix without the involvement of nixos.

|-

|How do you select your official sources and major releases

|At any time you select from a collection of channels. They're system-wide when set by root. You can roll back changes or switch channels with ease.

|Channels are per-user if they're not set by root.

|-

|Where are packages installed?

|System-wide packages are in /run/current-system/sw/ (these are installed because of /etc/nixos/configuration.nix) and /nix/var/nix/profiles/default/bin/ (this is the profile managed by root). Note that the files are just symlinks to the real packages managed by nix /nix/store/.

|User packages are in ~/.nix-profile/. Note that the files are just symlinks to the real packages managed by nix in /nix/store/.

|-

|When changes take effect

|Most of the time you apply changes with nix-env -i all

TODO How does one get nix to do all the work for a switch and separate out the actual switching from fetching/building?

|-

|Packages

|Technically called "derivations" but everyone calls them packages.

|Technically called "derivations" but everyone calls them packages.

|-

| colspan="5" style="text-align:center"| Package management

Or with collections, add the package to your ~/.nixpkgs/config.nix and run

<pre>nix-env -i all</pre>

|-

|Uninstall a package

|remove from /etc/nixos/configuration.nix

<pre>sudo nixos-rebuild switch</pre>

|

|-

|<pre>apt-get purge emacs</pre>

|All configuration is in configuration.nix

|

|-

|<pre>sudo nix-channel --update</pre>

|<pre>nix-channel --update</pre>

|-

|Upgrade packages

|<pre>sudo nixos-rebuild switch</pre>

|<pre>nix-env -u</pre>

|-

|Check for broken dependencies

|<pre>nix-store --verify --check-contents</pre>

|unneeded!

|-

|List package dependencies

For installed packages:

<pre>nix-store --query --references $(which emacs)</pre>

|-

|List which packages depend on this one (reverse dependencies)

|For installed packages (only print reverse dependencies *which are already installed*):

<pre>nix-store --query --referrers $(which emacs)</pre>

|-

|Verify all installed packages

|<pre>sudo nix-store --verify --check-contents</pre>

|<pre>nix-store --verify --check-contents</pre>

|-

|Fix packages with failed checksums

|<pre>sudo nix-store --verify --check-contents --repair</pre>

|<pre>nix-store --verify --check-contents --repair</pre>

|-

|Select major version and stable/unstable

To show all installed channel.

|When run by a user channels work locally, when run by root they're used as the system-wide channels.

|-

|Private package repository

|Define your package tree as in the general column, and include it in configuration.nix, then list your packages in systemPackages to make them available system wide

|See [https://sandervanderburg.blogspot.de/2014/07/managing-private-nix-packages-outside.html]

|-

|Install a particular version of a package

|

|

|edit /etc/nixos/configuration.nix

|edit ~/.nixpkgs/config.nix TODO More details about how to edit

|-

|List package options

|

|

|Global package configuration

|Modify configuration file in /etc/

|

|

|<pre>nix-env -qaP '.*emacs.*'</pre>

|<pre>nix-env -qaP '.*emacs.*'</pre>

|-

|Show package description

|<pre>nix-env -qa --description '.*emacs.*'</pre>

|<pre>nix-env -qa --description '.*emacs.*'</pre>

|-

|Show files installed by package

<pre>du -a /nix/store/ji06y4haijly0i0knmr986l2dajffv1p-emacs-24.4</pre>

|<pre></pre>

|-

|Show package for file

|follow the symlink

|follow the symlink

|-

| colspan="5" style="text-align:center"| Services

|<pre>sudo service apache start</pre>

|<pre>sudo systemctl start apache</pre>

|

|-

|<pre>sudo service apache stop</pre>

|<pre>sudo systemctl stop apache</pre>

|

|-

|System-wide packages /var/log/

|User packages ~/.nix-profile/var/log/

|-

|Adding a user

       [ "ssh-dss AAAAB3Nza... alice@foobar" ];

  };</pre> to to /etc/nixos/configuration.nix and then call <pre>nixos-rebuild switch</pre>

|

|-

ls /nix/var/nix/profiles/default/bin/</pre>

|<pre>ls ~/.nix-profile/bin</pre>

|-

|Get the current version number

|<pre>nixos-version</pre>

|<pre>nixos-version</pre>

|-

|Get sources for a package

The patched source is usually not a derivation itself, but can be produced for most packages with the following command: <pre>nix-shell '<nixpkgs>' -A emacs\

   --command 'unpackPhase; patchPhase'</pre>

|-

|Compile & install a package from source

EOF

nix-build</pre>

|-

|Install a binary package

|

|

|

|Install dpkg with Nix, then <pre>dpkg -i package.deb</pre>

|}