nix-env(1)
omg hiii bestie π welcome to the nix-env(1) page, straight outta the General Commands Manual β no cap, this is the whole thing, I'm just making it cute for you β¨
β¨ Name β¨
nix-env β manipulate or query Nix user environments π
π Synopsis π
nix-env operation [options] [argumentsβ¦] [--option name value] [--arg name value] [--argstr name value] [{--file | -f} path] [{--profile | -p} path] [--system-filter system] [--dry-run]
π Description π
The command nix-env is your go-to for manipulating Nix user environments. User environments are literally sets of software packages available to a user at some point in time. In other words, they're a synthesised view of the programs available in the Nix store β¨. There may be many user environments: different users can have different environments, and individual users can switch between different environments. it's giving β¨personalizationβ¨, periodt.
nix-env takes exactly one operation flag which indicates the subcommand to be performed. The following operations are available:
--install--upgrade--uninstall--set--set-flag--query--switch-profile--list-generations--delete-generations--switch-generation--rollback
These pages can be viewed offline:
man nix-env-<operation>.
Example: man nix-env-install
nix-env --help --<operation>
Example: nix-env --help --install
π¦ Package sources π¦
nix-env can obtain packages from multiple sources:
- An attribute set of derivations from:
- The default Nix expression (by default)
- A Nix file, specified via
--file - A profile, specified via
--from-profile - A Nix expression that is a function which takes default expression as argument, specified via
--from-expression
- A store path
πΈ Selectors πΈ
Several operations, such as nix-env --query and nix-env --install, take a list of arguments that specify the packages on which to operate.
Packages are identified based on a name part and a version part of a symbolic derivation name:
- name: Everything up to but not including the first dash (
-) that is not followed by a letter. - version: The rest, excluding the separating dash.
Example
nix-env parses the symbolic derivation name apache-httpd-2.0.48 as:
{
"name": "apache-httpd",
"version": "2.0.48"
}
Example
nix-env parses the symbolic derivation name firefox.* as:
{
"name": "firefox.*",
"version": ""
}
The name parts of the arguments to nix-env are treated as extended regular expressions and matched against the name parts of derivation names in the package source. The match is case-sensitive. The regular expression can optionally be followed by a dash (-) and a version number; if omitted, any version of the package will match. For details on regular expressions, see regex(7).
Example
Common patterns for finding package names with nix-env:
firefoxβ Matches the package namefirefoxand any version.firefox-32.0β Matches the package namefirefoxand version32.0.gtk\\+β Matches the package namegtk+. The+character must be escaped using a backslash (\) to prevent it from being interpreted as a quantifier, and the backslash must be escaped in turn with another backslash to ensure that the shell passes it on..\*β Matches any package name. This is the default for most commands.'.*zip.*'β Matches any package name containing the stringzip. Note the dots:'*zip*'does not work, because in a regular expression, the character*is interpreted as a quantifier.'.*(firefox|chromium).*'β Matches any package name containing the stringsfirefoxorchromium.
π Files π
nix-env operates on the following files.
π Default Nix expression π
The source for the Nix expressions used by nix-env by default:
~/.nix-defexpr$XDG_STATE_HOME/nix/defexprifuse-xdg-base-directoriesis set totrue.
It is loaded as follows:
- If the default expression is a file, it is loaded as a Nix expression.
- If the default expression is a directory containing a
default.nixfile, thatdefault.nixfile is loaded as a Nix expression. - If the default expression is a directory without a
default.nixfile, then its contents (both files and subdirectories) are loaded as Nix expressions. The expressions are combined into a single attribute set, each expression under an attribute with the same name as the original file or subdirectory. Subdirectories without adefault.nixfile are traversed recursively in search of more Nix expressions, but the names of these intermediate directories are not added to the attribute paths of the default Nix expression.
Then, the resulting expression is interpreted like this:
- If the expression is an attribute set, it is used as the default Nix expression.
- If the expression is a function, an empty set is passed as argument and the return value is used as the default Nix expression.
Example
If the default expression contains two files, foo.nix and bar.nix, then the default Nix expression will be equivalent to
{
foo = import ~/.nix-defexpr/foo.nix;
bar = import ~/.nix-defexpr/bar.nix;
}
The file manifest.nix is always ignored.
The command nix-channel places a symlink to the current userβs channels in this directory, the user channel link. This makes all subscribed channels available as attributes in the default expression.
π User channel link π
A symlink that ensures that nix-env can find the current userβs channels:
~/.nix-defexpr/channels$XDG_STATE_HOME/nix/defexpr/channelsifuse-xdg-base-directoriesis set totrue.
This symlink points to:
$XDG_STATE_HOME/nix/profiles/channelsfor regular users$NIX_STATE_DIR/profiles/per-user/root/channelsfor root
In a multi-user installation, you may also have ~/.nix-defexpr/channels_root, which links to the channels of the root user.
π§ Profiles π§
A directory that contains links to profiles managed by nix-env and nix profile:
$XDG_STATE_HOME/nix/profilesfor regular users$NIX_STATE_DIR/profiles/per-user/rootif the user is root
A profile is a directory of symlinks to files in the Nix store.
π Filesystem layout π
Profiles are versioned as follows. When using a profile named path, path is a symlink to path-N-link, where N is the version of the profile. In turn, path-N-link is a symlink to a path in the Nix store. For example:
$ ls -l ~alice/.local/state/nix/profiles/profile*
lrwxrwxrwx 1 alice users 14 Nov 25 14:35 /home/alice/.local/state/nix/profiles/profile -> profile-7-link
lrwxrwxrwx 1 alice users 51 Oct 28 16:18 /home/alice/.local/state/nix/profiles/profile-5-link -> /nix/store/q69xad13ghpf7ir87h0b2gd28lafjj1j-profile
lrwxrwxrwx 1 alice users 51 Oct 29 13:20 /home/alice/.local/state/nix/profiles/profile-6-link -> /nix/store/6bvhpysd7vwz7k3b0pndn7ifi5xr32dg-profile
lrwxrwxrwx 1 alice users 51 Nov 25 14:35 /home/alice/.local/state/nix/profiles/profile-7-link -> /nix/store/mp0x6xnsg0b8qhswy6riqvimai4gm677-profile
Each of these symlinks is a root for the Nix garbage collector.
The contents of the store path corresponding to each version of the profile is a tree of symlinks to the files of the installed packages, e.g.
$ ll -R ~eelco/.local/state/nix/profiles/profile-7-link/
/home/eelco/.local/state/nix/profiles/profile-7-link/:
total 20
dr-xr-xr-x 2 root root 4096 Jan 1 1970 bin
-r--r--r-- 2 root root 1402 Jan 1 1970 manifest.nix
dr-xr-xr-x 4 root root 4096 Jan 1 1970 share
/home/eelco/.local/state/nix/profiles/profile-7-link/bin:
total 20
lrwxrwxrwx 5 root root 79 Jan 1 1970 chromium -> /nix/store/cyxny9d1zjb9l9103fr6j6kavp3bqjxf-chromium-86.0.4240.111/bin/chromium
lrwxrwxrwx 7 root root 87 Jan 1 1970 spotify -> /nix/store/w9182874m1bl56smps3m5zjj36jhp3rn-spotify-1.1.26.501.gbe11e53b-15/bin/spotify
lrwxrwxrwx 3 root root 79 Jan 1 1970 zoom-us -> /nix/store/wbhg2ga8f3h87s9h5k0slxk0m81m4cxl-zoom-us-5.3.469451.0927/bin/zoom-us
/home/eelco/.local/state/nix/profiles/profile-7-link/share/applications:
total 12
lrwxrwxrwx 4 root root 120 Jan 1 1970 chromium-browser.desktop -> /nix/store/sqzyx2l85i6j2a77pnyvglh3bvzwmjjp-chromium-unwrapped-86.0.4240.111/share/applications/chromium-browser.desktop
lrwxrwxrwx 7 root root 110 Jan 1 1970 spotify.desktop -> /nix/store/w9182874m1bl56smps3m5zjj36jhp3rn-spotify-1.1.26.501.gbe11e53b-15/share/applications/spotify.desktop
lrwxrwxrwx 3 root root 107 Jan 1 1970 us.zoom.Zoom.desktop -> /nix/store/wbhg2ga8f3h87s9h5k0slxk0m81m4cxl-zoom-us-5.3.469451.0927/share/applications/us.zoom.Zoom.desktop
β¦
Each profile version contains a manifest file:
manifest.nixused bynix-env.manifest.jsonused bynix profile(experimental).
π¦ User profile link π¦
A symbolic link to the userβs current profile:
~/.nix-profile$XDG_STATE_HOME/nix/profileifuse-xdg-base-directoriesis set totrue.
By default, this symlink points to:
$XDG_STATE_HOME/nix/profiles/profilefor regular users$NIX_STATE_DIR/profiles/per-user/root/profilefor root
The PATH environment variable should include /bin subdirectory of the profile link (e.g. ~/.nix-profile/bin) for the user environment to be visible to the user. The installer sets this up by default, unless you enable use-xdg-base-directories.
okay bestie, that's literally the whole nix-env(1) page π you're officially smarter than before, no cap. now go slay those environments β¨π
π¦ where this page comes from
- fedora 44: nix-legacy 2.35.3-2.fc44 Β· LGPL-2.1-or-later
- π girlified by deepseek-ai/DeepSeek-V4.1-Flash on : a language model's rewrite of the original, under its terms