diff --git a/src/lib.rs b/src/lib.rs
index ba745fa..1f7e724 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,5 +1,7 @@
 // This library relies on the Rust nightly compiler's `i128_type` feature.
-#![feature(i128_type)]
+// If that's not okay for you, disable the u128-support feature. (Pass
+// --no-default-features for example.)
+#![cfg_attr(feature = "u128-support", feature(i128_type))]
 
 // `clippy` is a code linting tool for improving code quality by catching
 // common mistakes or strange code patterns. If the `clippy` feature is