diff --git a/pkgs/by-name/li/libcbor/package.nix b/pkgs/by-name/li/libcbor/package.nix
index a5e1585e8489..a38b9cafac55 100644
--- a/pkgs/by-name/li/libcbor/package.nix
+++ b/pkgs/by-name/li/libcbor/package.nix
@@ -35,6 +35,10 @@ stdenv.mkDerivation (finalAttrs: {
     cmocka # cmake expects cmocka module
   ];
 
+  # BUILD file already exists in the source
+  # TODO: make unconditional on staging.
+  cmakeBuildDir = if stdenv.isDarwin then "build.dir" else null;
+
   cmakeFlags =
     lib.optional finalAttrs.finalPackage.doCheck "-DWITH_TESTS=ON"
     ++ lib.optional (!stdenv.hostPlatform.isStatic) "-DBUILD_SHARED_LIBS=ON";