Pinning Nixpkgs#
Specifying remote Nix expressions, such as the one provided by Nixpkgs, can be done in several ways:
-I
option to most of commands likenix-build
,nix-shell
, etc.fetchurl
,fetchTarball
,fetchGit
or Nixpkgs fetchers in Nix expressions
Possible URL values#
Local file path:
./path/to/expression.nix
Using
./.
means that the expression is located in a filedefault.nix
in the current directory.Pinned to a specific commit:
https://github.com/NixOS/nixpkgs/archive/eabc38219184cc3e04a974fe31857d8e0eac098d.tar.gz
Using the latest channel version, meaning all tests have passed:
http://nixos.org/channels/nixos-22.11/nixexprs.tar.xz
Shorthand syntax for channels:
channel:nixos-22.11
Using the latest channel version, hosted by GitHub:
https://github.com/NixOS/nixpkgs/archive/nixos-22.11.tar.gz
Using the latest commit on the release branch, but not tested yet:
https://github.com/NixOS/nixpkgs/archive/release-21.11.tar.gz
Examples#
$ nix-build -I ~/dev
$ nix-build -I nixpkgs=http://nixos.org/channels/nixos-22.11/nixexprs.tar.xz
$ nix-build -I nixpkgs=channel:nixos-22.11
$ NIX_PATH=nixpkgs=http://nixos.org/channels/nixos-22.11/nixexprs.tar.xz nix-build
$ NIX_PATH=nixpkgs=channel:nixos-22.11 nix-build
In the Nix language:
1let 2 pkgs = import (fetchTarball "https://github.com/NixOS/nixpkgs/archive/nixos-22.11.tar.gz") {}; 3in pkgs.stdenv.mkDerivation { ... }