{ writeScriptBin, stdenv, lib, elm, }: let patchNpmElm = pkg: pkg.override (old: { preRebuild = (old.preRebuild or "") + '' rm node_modules/elm/install.js echo "console.log('Nixpkgs\' version of Elm will be used');" > node_modules/elm/install.js ''; postInstall = (old.postInstall or "") + '' ln -sf ${elm}/bin/elm node_modules/elm/bin/elm ''; }); in { inherit patchNpmElm; }