diff --git a/src/lib.rs b/src/lib.rs
index 9c42014..97cccc9 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,5 +1,4 @@
-#![feature(external_doc, clamp)]
-#![doc(include = "../README.md")]
+#![doc = include_str!("../README.md")]
 
 pub mod accumulation_buffer;
 mod camera;