Name
nix-env - manipulate or query Nix user environments
Synopsis
nix-env operation [options] [arguments…]
[--option name value]
[--arg name value]
[--argstr name value]
[{--file | -f} path]
[{--profile | -p} path]
[--system-filter system]
[--dry-run]
Description
The command nix-env is used to manipulate Nix user environments. User
environments are sets of software packages available to a user at some
point in time. In other words, they are a synthesised view of the
programs available in the Nix store. There may be many user
environments: different users can have different environments, and
individual users can switch between different environments.
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
Selectors
Several commands, such as nix-env -q and nix-env -i, take a list of
arguments that specify the packages on which to operate. These are
extended regular expressions that must match the entire name of the
package. (For details on regular expressions, see regex(7).) 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. Here are some examples:
-
firefox
Matches the package namefirefoxand any version. -
firefox-32.0
Matches the package namefirefoxand version32.0. -
gtk\\+
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. -
.\*
Matches any package name. This is the default for most commands. -
'.*zip.*'
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).*'
Matches any package name containing the stringsfirefoxorchromium.
Files
-
~/.nix-defexpr
The source for the default Nix expressions used by the--install,--upgrade, and--query --availableoperations to obtain derivations. The--fileoption may be used to override this default.If
~/.nix-defexpris a file, it is loaded as a Nix expression. If the expression is a 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.If
~/.nix-defexpris a directory containing adefault.nixfile, that file is loaded as in the above paragraph.If
~/.nix-defexpris a directory without adefault.nixfile, then its contents (both files and subdirectories) are loaded as Nix expressions. The expressions are combined into a single set, each expression under an attribute with the same name as the original file or subdirectory.For example, if
~/.nix-defexprcontains two files,foo.nixandbar.nix, then the default Nix expression will essentially be{ foo = import ~/.nix-defexpr/foo.nix; bar = import ~/.nix-defexpr/bar.nix; }The file
manifest.nixis always ignored. 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.The command
nix-channelplaces symlinks to the downloaded Nix expressions from each subscribed channel in this directory. -
~/.nix-profile
A symbolic link to the user's current profile. By default, this symlink points toprefix/var/nix/profiles/default. ThePATHenvironment variable should include~/.nix-profile/binfor the user environment to be visible to the user.