There are a couple of functions provide in Nixpkgs that help with building derivations. The most important one, stdenv.mkDerivation, has already been documented above. These wrap stdenv.mkDerivation, making it easier to use in certain cases. runCommand This takes three arguments, name, env, and buildCommand. name is just the name that Nix will use to refer to the derivation. env is an attribute set specifying environment variables that will be set for this derivation. buildCommand specifies the commands that will be run to create this derivation. Note that you will need to create $out for Nix to register the command as successful. runCommandCC This works just like runCommand. The only difference is that it also provides a C compiler for your use. To minimize your dependencies, you should only use this if you are sure you will need a C compiler as part of running your command. writeTextFile This writes text to the Nix store. This is useful for creating scripts from Nix expressions. This takes an attribute set and expects two arguments, name and text. name corresponds to the name used in the Nix store path. text will be the contents of the file. You can also set executable to true to make this file have the executable bit set. symlinkJoin This can be used to put many derivations into the same directory structure. It works by creating a new derivation and adding symlinks to each of the paths listed. It expects two arguments, name, and paths. name is the name used in the Nix store path for the created derivation. paths is a list of paths that will be symlinked. These paths can be to Nix store derivations or any other directory.