diff --git a/katexit-example-nightly/src/lib.rs b/katexit-example-nightly/src/lib.rs
index 7828b4c..63fc668 100644
--- a/katexit-example-nightly/src/lib.rs
+++ b/katexit-example-nightly/src/lib.rs
@@ -1,6 +1,9 @@
 #![feature(prelude_import, custom_inner_attributes)]
 #![cfg_attr(doc, katexit::katexit)]
 //! Module level document example with $\KaTeX$!
+//!
+//! This requires nightly rustc for using [custom_inner_attributes](https://github.com/rust-lang/rust/issues/54726)
+//!
 
 #[cfg_attr(doc, katexit::katexit)]
 /// We can write $\LaTeX$ expressions