diff --git a/components/style/servo/mod.rs b/components/style/servo/mod.rs
index fd7f1b7c566..29025b432a7 100644
--- a/components/style/servo/mod.rs
+++ b/components/style/servo/mod.rs
@@ -2,5 +2,9 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+//! Servo-specific bits of the style system.
+//!
+//! These get compiled out on a Gecko build.
+
 pub mod restyle_damage;
 pub mod selector_parser;