diff --git a/pkgs/applications/video/obs-studio/plugins/obs-source-record.nix b/pkgs/applications/video/obs-studio/plugins/obs-source-record.nix
index 9bc5f5683011..f4d4caa3ff46 100644
--- a/pkgs/applications/video/obs-studio/plugins/obs-source-record.nix
+++ b/pkgs/applications/video/obs-studio/plugins/obs-source-record.nix
@@ -20,7 +20,7 @@ stdenv.mkDerivation rec {
   nativeBuildInputs = [ cmake ];
   buildInputs = [ obs-studio ];
 
-  NIX_CFLAGS_COMPILE = [ "-Wno-error=deprecated-declarations" ];
+  env.NIX_CFLAGS_COMPILE = toString [ "-Wno-error=deprecated-declarations" ];
 
   cmakeFlags = [ "-DBUILD_OUT_OF_TREE=On" ];