diff --git a/pkgs/development/libraries/mono-addins/default.nix b/pkgs/development/libraries/mono-addins/default.nix
index 345c6e51f0b7..ca72557242f1 100644
--- a/pkgs/development/libraries/mono-addins/default.nix
+++ b/pkgs/development/libraries/mono-addins/default.nix
@@ -27,5 +27,6 @@ stdenv.mkDerivation rec {
       and for creating libraries which extend those applications.
     '';
     platforms = platforms.linux;
+    license = licenses.mit;
   };
 }