diff --git a/pkgs/os-specific/linux/kernel/manual-config.nix b/pkgs/os-specific/linux/kernel/manual-config.nix
index 377f7fc1c077..7e734a4f13ab 100644
--- a/pkgs/os-specific/linux/kernel/manual-config.nix
+++ b/pkgs/os-specific/linux/kernel/manual-config.nix
@@ -334,7 +334,7 @@ stdenv.mkDerivation ((drvAttrs config stdenv.hostPlatform.linux-kernel kernelPat
     "CC=${stdenv.cc}/bin/${stdenv.cc.targetPrefix}cc"
     "HOSTCC=${buildPackages.stdenv.cc}/bin/${buildPackages.stdenv.cc.targetPrefix}cc"
     "ARCH=${stdenv.hostPlatform.linuxArch}"
-  ] ++ lib.optional (stdenv.hostPlatform != stdenv.buildPlatform) [
+  ] ++ lib.optionals (stdenv.hostPlatform != stdenv.buildPlatform) [
     "CROSS_COMPILE=${stdenv.cc.targetPrefix}"
   ] ++ (stdenv.hostPlatform.linux-kernel.makeFlags or [])
     ++ extraMakeFlags;