diff --git a/src/error.rs b/src/error.rs
index 9d6de82c..13e13b82 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -38,6 +38,7 @@ impl fmt::Display for Unexpected {
 
 /// Represents all possible errors that can occur when working with
 /// configuration.
+#[non_exhaustive]
 pub enum ConfigError {
     /// Configuration is frozen and no further mutations can be made.
     Frozen,