diff --git a/src/engine.rs b/src/engine.rs
index 5c4fdaee..70e93568 100644
--- a/src/engine.rs
+++ b/src/engine.rs
@@ -340,6 +340,7 @@ pub fn get_script_function_by_signature<'a>(
 ///
 /// This type is volatile and may change.
 #[cfg(not(feature = "unchecked"))]
+#[derive(Debug, Clone, Eq, PartialEq, Hash)]
 pub struct Limits {
     /// Maximum levels of call-stack to prevent infinite recursion.
     ///
@@ -377,6 +378,7 @@ pub struct Limits {
 /// ```
 ///
 /// Currently, `Engine` is neither `Send` nor `Sync`. Use the `sync` feature to make it `Send + Sync`.
+#[derive(Clone)]
 pub struct Engine {
     /// A unique ID identifying this scripting `Engine`.
     pub id: Option<String>,