diff --git a/pkgs/development/interpreters/spidermonkey/185-1.0.0.nix b/pkgs/development/interpreters/spidermonkey/185-1.0.0.nix
index 47652966cec..a036388f15e 100644
--- a/pkgs/development/interpreters/spidermonkey/185-1.0.0.nix
+++ b/pkgs/development/interpreters/spidermonkey/185-1.0.0.nix
@@ -21,7 +21,7 @@ stdenv.mkDerivation rec {
   '';
 
   # Explained below in configureFlags for ARM
-  patches = stdenv.lib.optionals stdenv.isARM [
+  patches = stdenv.lib.optionals stdenv.isArm [
     ./findvanilla.patch
   ];