diff --git a/01.workspace/heave/examples/simple_product.rs b/01.workspace/heave/examples/simple_product.rs
index 69c1a2b..cadeba6 100644
--- a/01.workspace/heave/examples/simple_product.rs
+++ b/01.workspace/heave/examples/simple_product.rs
@@ -1,6 +1,7 @@
 use heave::*;
 
 // Define a struct named `Product` to represent a product.
+#[derive(PartialEq)]
 struct Product {
     // `id` is a public field of type `String` to uniquely identify the product.
     pub id: String,
diff --git a/01.workspace/heave/examples/working_with_many_types.rs b/01.workspace/heave/examples/working_with_many_types.rs
index c4cab2d..5221a09 100644
--- a/01.workspace/heave/examples/working_with_many_types.rs
+++ b/01.workspace/heave/examples/working_with_many_types.rs
@@ -1,23 +1,27 @@
 use heave::*;
 use std::path::Path;
 
+#[derive(PartialEq)]
 struct Laptop {
     pub id: String,
     pub model: String,
     pub price: u64,
 }
+#[derive(PartialEq)]
 struct Display {
     pub id: String,
     pub model: String,
     pub resolution: f64,
     pub price: u64,
 }
+#[derive(PartialEq)]
 struct Mouse {
     pub id: String,
     pub model: String,
     pub wireless: bool,
     pub price: u64,
 }
+#[derive(PartialEq)]
 enum Product {
     None,
     Laptop(Laptop),
diff --git a/01.workspace/heave/src/trt/eav.rs b/01.workspace/heave/src/trt/eav.rs
index 6115c78..2a872de 100644
--- a/01.workspace/heave/src/trt/eav.rs
+++ b/01.workspace/heave/src/trt/eav.rs
@@ -7,6 +7,7 @@ use crate::*;
 pub trait T where
     Self: TryFrom<Entity>,
     Self: TryInto<Entity>,
+    Self: PartialEq,
 {
     /// Returns the class name of the type.
     ///