diff --git a/pkgs/applications/misc/xmrig-proxy/default.nix b/pkgs/applications/misc/xmrig-proxy/default.nix
index 04bc239ea5b..248f629f2e9 100644
--- a/pkgs/applications/misc/xmrig-proxy/default.nix
+++ b/pkgs/applications/misc/xmrig-proxy/default.nix
@@ -16,6 +16,7 @@ stdenv.mkDerivation rec {
   nativeBuildInputs = [ cmake ];
   buildInputs = [ libuv libmicrohttpd libuuid ];
 
+  # Set default donation level to 0%. Can be increased at runtime via --donate-level option.
   postPatch = ''
     substituteInPlace src/donate.h --replace "kDonateLevel = 2;" "kDonateLevel = ${toString donateLevel};"
   '';