diff --git a/pkgs/build-support/binary-cache/default.nix b/pkgs/build-support/binary-cache/default.nix
index 577328cad920..27f9ad962899 100644
--- a/pkgs/build-support/binary-cache/default.nix
+++ b/pkgs/build-support/binary-cache/default.nix
@@ -1,4 +1,4 @@
-{ stdenv, buildPackages }:
+{ lib, stdenv, buildPackages }:
 
 # This function is for creating a flat-file binary cache, i.e. the kind created by
 # nix copy --to file:///some/path and usable as a substituter (with the file:// prefix).
@@ -19,7 +19,7 @@ stdenv.mkDerivation {
 
   preferLocalBuild = true;
 
-  PATH = "${buildPackages.coreutils}/bin:${buildPackages.jq}/bin:${buildPackages.python3}/bin:${buildPackages.nix}/bin:${buildPackages.xz}/bin";
+  PATH = lib.makeBinPath (with buildPackages; [ coreutils jq python3 nix xz ]);
 
   builder = builtins.toFile "builder" ''
     . .attrs.sh