diff --git a/pkgs/build-support/testers/default.nix b/pkgs/build-support/testers/default.nix
index 361517507bc7..705946e0eab7 100644
--- a/pkgs/build-support/testers/default.nix
+++ b/pkgs/build-support/testers/default.nix
@@ -104,7 +104,7 @@
   # See https://nixos.org/manual/nixpkgs/unstable/#tester-runCommand
   runCommand = testers.invalidateFetcherByDrvHash (
     {
-      hash ? "sha256-d6xi4mKdjkX2JFicDIv5niSzpyI0m/Hnm8GGAIU04kY=", # hash value of empty file
+      hash ? pkgs.emptyFile.outputHash,
       name,
       script,
       stdenv ? stdenvNoCC,
diff --git a/pkgs/build-support/trivial-builders/default.nix b/pkgs/build-support/trivial-builders/default.nix
index fc6f07fdd11b..686819725d59 100644
--- a/pkgs/build-support/trivial-builders/default.nix
+++ b/pkgs/build-support/trivial-builders/default.nix
@@ -887,9 +887,8 @@ rec {
   /* An immutable file in the store with a length of 0 bytes. */
   emptyFile = runCommand "empty-file"
     {
-      outputHashAlgo = "sha256";
+      outputHash = "sha256-d6xi4mKdjkX2JFicDIv5niSzpyI0m/Hnm8GGAIU04kY=";
       outputHashMode = "recursive";
-      outputHash = "0ip26j2h11n1kgkz36rl4akv694yz65hr72q4kv4b3lxcbi65b3p";
       preferLocalBuild = true;
     } "touch $out";