lix/doc/manual/src/command-ref/nix-env.md

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 --query and nix-env --install , 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 name firefox and any version.

• firefox-32.0
  Matches the package name firefox and version 32.0.

• gtk\\+
  Matches the package name gtk+. 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 string zip. 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 strings firefox or chromium.

Files

nix-env operates on the following files.

{{#include ./files/default-nix-expression.md}}

{{#include ./files/profiles.md}}