diff --git a/src/error.rs b/src/error.rs
index df8cc50..06457fc 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -35,3 +35,5 @@ impl From<std::num::ParseIntError> for Error {
         NumParseError
     }
 }
+
+impl std::error::Error for Error {}
diff --git a/src/lib.rs b/src/lib.rs
index 33ff39f..3f1c870 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -98,3 +98,8 @@ Digest username="Mufasa",
         .trim()
     );
 }
+
+#[test]
+fn test_cast_error() {
+    let _m : Box<dyn std::error::Error> = Error::UnknownAlgorithm("Uhhh".into()).into();
+}