Options

The following options are allowed for all nix-env operations, but may not always have an effect.

• --file / -f fileish
  Specifies the Nix expression (designated below as the active Nix expression) used by the --install, --upgrade, and --query --available operations to obtain derivations. The default is ~/.nix-defexpr.

  fileish is interpreted the same as with nix-build. See that section for complete details (nix-build --help), but in summary, a path argument may be one of:

  {{#include ../fileish-summary.md}}

• --profile / -p path
  Specifies the profile to be used by those operations that operate on a profile (designated below as the active profile). A profile is a sequence of user environments called generations, one of which is the current generation.

• --dry-run
  For the --install, --upgrade, --uninstall, --switch-generation, --delete-generations and --rollback operations, this flag will cause nix-env to print what would be done if this flag had not been specified, without actually doing it.

  --dry-run also prints out which paths will be substituted (i.e., downloaded) and which paths will be built from source (because no substitute is available).

• --system-filter system
  By default, operations such as --query --available show derivations matching any platform. This option allows you to use derivations for the specified platform system.