nix-env-install - Man Page

nix-env {--install | -i} args… [{--prebuilt-only | -b}] [{--attr | -A}] [--from-expression] [-E] [--from-profile path] [--preserve-installed | -P] [--remove-all | -r] [--priority priority]

The --install operation creates a new user environment. It is based on the current generation of the active profile , to which a set of store paths described by args is added.

The arguments args map to store paths in a number of possible ways:

• By default, args is a set of names denoting derivations in the default Nix expression . These are realised , and the resulting output paths are installed. Currently installed derivations with a name equal to the name of a derivation being added are removed unless the option --preserve-installed is specified.

  If there are multiple derivations matching a name in args that have the same name (e.g., gcc-3.3.6 and gcc-4.1.1), then the derivation with the highest priority is used. A derivation can define a priority by declaring the meta.priority attribute. This attribute should be a number, with a higher value denoting a lower priority. The default priority is 5.

  If there are multiple matching derivations with the same priority, then the derivation with the highest version will be installed.

  You can force the installation of multiple derivations with the same name by being specific about the versions. For instance, nix-env --install gcc-3.3.6 gcc-4.1.1 will install both version of GCC (and will probably cause a user environment conflict!).

• If --attr / -A is specified, the arguments are attribute paths that select attributes from the default Nix expression . This is faster than using derivation names and unambiguous. Show the attribute paths of available packages with nix-env --query :

nix-env --query --available --attr-path

• If --from-profile path is given, args is a set of names denoting installed store paths in the profile path. This is an easy way to copy user environment elements from one profile to another.
• If --from-expression is given, args are Nix language functions that are called with the default Nix expression as their single argument. The derivations returned by those function calls are installed. This allows derivations to be specified in an unambiguous way, which is necessary if there are multiple derivations with the same name.
• If --priority priority is given, the priority of the derivations being installed is set to priority. This can be used to override the priority of the derivations being installed. This is useful if args are store paths , which don't have any priority information.
• If args are store paths that point to store derivations , then those store derivations are realised , and the resulting output paths are installed.
• If args are store paths that do not point to store derivations, then these are realised and installed.

• By default all outputs are installed for each store derivation . This can be overridden by adding a meta.outputsToInstall attribute on the derivation listing a subset of the output names.

  Example:

  The file example.nix defines a derivation with two outputs foo and bar, each containing a file.

# example.nix
let
pkgs = import <nixpkgs> {};
command = ''
  ${pkgs.coreutils}/bin/mkdir -p $foo $bar
  echo foo > $foo/foo-file
  echo bar > $bar/bar-file
'';
in
derivation {
name = "example";
builder = "${pkgs.bash}/bin/bash";
args = [ "-c" command ];
outputs = [ "foo" "bar" ];
system = builtins.currentSystem;
}

Installing from this Nix expression will make files from both outputs appear in the current profile.

$ nix-env --install --file example.nix
installing 'example'
$ ls ~/.nix-profile
foo-file
bar-file
manifest.nix

Adding meta.outputsToInstall to that derivation will make nix-env only install files from the specified outputs.

# example-outputs.nix
import ./example.nix // { meta.outputsToInstall = [ "bar" ]; }

$ nix-env --install --file example-outputs.nix
installing 'example'
$ ls ~/.nix-profile
bar-file
manifest.nix

• --prebuilt-only / -b

  Use only derivations for which a substitute is registered, i.e., there is a pre-built binary available that can be downloaded in lieu of building the derivation. Thus, no packages will be built from source.

• --preserve-installed / -P

  Do not remove derivations with a name matching one of the derivations being installed. Usually, trying to have two versions of the same package installed in the same generation of a profile will lead to an error in building the generation, due to file name clashes between the two versions. However, this is not the case for all packages.

• --remove-all / -r

  Remove all previously installed packages first. This is equivalent to running nix-env --uninstall '.*' first, except that everything happens in a single transaction.

{{#include ./opt-common.md}}

{{#include ../opt-common.md}}

{{#include ./env-common.md}}

{{#include ../env-common.md}}

To install a package using a specific attribute path from the active Nix expression:

$ nix-env --install --attr gcc40mips
installing `gcc-4.0.2'
$ nix-env --install --attr xorg.xorgserver
installing `xorg-server-1.2.0'

To install a specific version of gcc using the derivation name:

$ nix-env --install gcc-3.3.2
installing `gcc-3.3.2'
uninstalling `gcc-3.1'

Using attribute path for selecting a package is preferred, as it is much faster and there will not be multiple matches.

Note the previously installed version is removed, since --preserve-installed was not specified.

To install an arbitrary version:

$ nix-env --install gcc
installing `gcc-3.3.2'

To install all derivations in the Nix expression foo.nix:

$ nix-env --file ~/foo.nix --install '.*'

To copy the store path with symbolic name gcc from another profile:

$ nix-env --install --from-profile /nix/var/nix/profiles/foo gcc

To install a specific store derivation\c :

$ nix-env --install /nix/store/fibjb1bfbpm5mrsxc4mh2d8n37sxh91i-gcc-3.4.3.drv

To install a specific output path:

$ nix-env --install /nix/store/y3cgx0xj1p4iv9x0pnnmdhr8iyg741vk-gcc-3.4.3

To install from a Nix expression specified on the command-line:

$ nix-env --file ./foo.nix --install --expr \
    'f: (f {system = "i686-linux";}).subversionWithJava'

I.e., this evaluates to (f: (f {system = "i686-linux";}).subversionWithJava) (import ./foo.nix), thus selecting the subversionWithJava attribute from the set returned by calling the function defined in ./foo.nix.

A dry-run tells you which paths will be downloaded or built from source:

$ nix-env --file '<nixpkgs>' --install --attr hello --dry-run
(dry run; not doing anything)
installing ‘hello-2.10’
this path will be fetched (0.04 MiB download, 0.19 MiB unpacked):
  /nix/store/wkhdf9jinag5750mqlax6z2zbwhqb76n-hello-2.10
  ...

To install Firefox from the latest revision in the Nixpkgs/NixOS 14.12 channel:

$ nix-env --file https://github.com/NixOS/nixpkgs/archive/nixos-14.12.tar.gz --install --attr firefox