diff --git a/pkgs/build-support/trivial-builders.nix b/pkgs/build-support/trivial-builders.nix
index bce5436353c..f9816b2d0d7 100644
--- a/pkgs/build-support/trivial-builders.nix
+++ b/pkgs/build-support/trivial-builders.nix
@@ -181,6 +181,7 @@ rec {
       outputHashAlgo = hashAlgo;
       outputHash = hash;
       preferLocalBuild = true;
+      allowSubstitutes = false;
       builder = writeScript "restrict-message" ''
         source ${stdenvNoCC}/setup
         cat <<_EOF_