diff --git a/nix/overlays/checked-shell-script/checked-shell-script.nix b/nix/overlays/checked-shell-script/checked-shell-script.nix
index df6f03d49..d541b59ae 100644
--- a/nix/overlays/checked-shell-script/checked-shell-script.nix
+++ b/nix/overlays/checked-shell-script/checked-shell-script.nix
@@ -104,8 +104,7 @@ let
         ''
 
         + lib.optionalString withTmpDir ''
-          mkdir -p "''${TMPDIR:-/tmp}/postgrest"
-          tmpdir="$(${coreutils}/bin/mktemp -d --tmpdir postgrest/${name}-XXX)"
+          tmpdir="$(${coreutils}/bin/mktemp -d --tmpdir ${name}-XXX)"
 
           # we keep the tmpdir when an error occurs for debugging
           trap 'echo Temporary directory kept at: $tmpdir' ERR