lib: self: let fetcherGenerators = { repo ? null , url ? null , ... }: { sha256 , commit , ...}: { github = self.callPackage ({ fetchFromGitHub }: fetchFromGitHub { owner = lib.head (lib.splitString "/" repo); repo = lib.head (lib.tail (lib.splitString "/" repo)); rev = commit; inherit sha256; } ) {}; gitlab = self.callPackage ({ fetchFromGitLab }: fetchFromGitLab { owner = lib.head (lib.splitString "/" repo); repo = lib.head (lib.tail (lib.splitString "/" repo)); rev = commit; inherit sha256; } ) {}; git = self.callPackage ({ fetchgit }: fetchgit { rev = commit; inherit sha256 url; } ) {}; bitbucket = self.callPackage ({ fetchhg }: fetchhg { rev = commit; url = "https://bitbucket.com/${repo}"; inherit sha256; } ) {}; hg = self.callPackage ({ fetchhg }: fetchhg { rev = commit; inherit sha256 url; } ) {}; }; in { melpaDerivation = variant: { ename, fetcher , commit ? null , sha256 ? null , ... }@args: let sourceArgs = args.${variant}; version = sourceArgs.version or null; deps = sourceArgs.deps or null; error = sourceArgs.error or args.error or null; hasSource = lib.hasAttr variant args; pname = builtins.replaceStrings [ "@" ] [ "at" ] ename; broken = ! isNull error; in lib.nameValuePair ename (if hasSource then ( self.callPackage ({ melpaBuild, fetchurl, ... }@pkgargs: melpaBuild { inherit pname; ename = ename; version = if isNull version then "" else lib.concatStringsSep "." (map toString version); # TODO: Broken should not result in src being null (hack to avoid eval errors) src = if (isNull sha256 || broken) then null else lib.getAttr fetcher (fetcherGenerators args sourceArgs); recipe = if isNull commit then null else fetchurl { name = pname + "-recipe"; url = "https://raw.githubusercontent.com/melpa/melpa/${commit}/recipes/${ename}"; inherit sha256; }; packageRequires = lib.optional (! isNull deps) (map (dep: pkgargs.${dep} or self.${dep} or null) deps); meta = (sourceArgs.meta or {}) // { inherit broken; }; } ) {} ) else null); }