diff --git a/src/lib.rs b/src/lib.rs
index 5aac5ec..6486ffb 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -48,6 +48,7 @@ use std::cell::UnsafeCell;
 use std::sync::atomic::{AtomicUsize, Ordering};
 
 /// A lazily filled `Cell`, with frozen contents.
+#[derive(Debug)]
 pub struct LazyCell<T> {
     inner: UnsafeCell<Option<T>>,
 }
@@ -121,6 +122,7 @@ const LOCK: usize = 1;
 const SOME: usize = 2;
 
 /// A lazily filled `Cell`, with frozen contents.
+#[derive(Debug)]
 pub struct AtomicLazyCell<T> {
     inner: UnsafeCell<Option<T>>,
     state: AtomicUsize,