{ # list of package attribute names to get at run time packageNamesAtRuntimeJsonPath , }: let pkgs = import { }; getPkg = pkgName: pkgs.${pkgName}; packageNamesAtRuntime = builtins.fromJSON (builtins.readFile packageNamesAtRuntimeJsonPath); runtime = map getPkg packageNamesAtRuntime; in pkgs.symlinkJoin { name = "symlink-farm"; paths = runtime; }