diff --git a/backend/crates/memory/src/lib.rs b/backend/crates/memory/src/lib.rs
index 82125db..39688d5 100644
--- a/backend/crates/memory/src/lib.rs
+++ b/backend/crates/memory/src/lib.rs
@@ -1,10 +1,10 @@
 //! # memory
 //!
-//! This crate provides in-memory implementations of the `Repository` trait for users and products.
+//! This crate provides in-memory implementations of the `Repository` trait for any entity type.
 //! It is primarily intended for testing, development, and CLI/TUI modes where persistence is not required.
 //!
 //! ## Features
-//! - Thread-safe, async in-memory storage for `User` and `Product` entities
+//! - Thread-safe, async in-memory storage for any entity type
 //! - Implements all CRUD operations
 //! - Used as a backend for memory-based API, CLI, and TUI binaries
 //! - Comprehensive unit tests for all repository and service operations
@@ -29,143 +29,158 @@ use tokio::sync::RwLock;
 use uuid::Uuid;
 
 use domain::{
-    CreateProduct, CreateUser, Product, Result, UpdateProduct, UpdateUser, User,
+    CreateProduct, CreateUser, Product, Result, UpdateProduct, UpdateUser, User, Entity,
 };
 use application::{Repository, Service};
 
+/// Generic trait for entities that can be stored in memory
+pub trait MemoryEntity: Entity + Clone + Send + Sync {
+    /// Get the entity's ID
+    fn id(&self) -> Uuid;
+    
+    /// Create a new entity from create data
+    fn from_create_data(data: Self::Create) -> Result<Self>;
+    
+    /// Update the entity with update data
+    fn update(&mut self, data: Self::Update) -> Result<()>;
+    
+    /// Get the entity name for error messages
+    fn entity_name() -> &'static str;
+}
+
+/// Generic, thread-safe, async in-memory repository for any entity type.
+///
+/// Implements all CRUD operations. Intended for testing and non-persistent use cases.
+#[derive(Default, Clone)]
+pub struct InMemoryRepository<T> {
+    entities: Arc<RwLock<HashMap<Uuid, T>>>,
+}
+
+impl<T: MemoryEntity> InMemoryRepository<T> {
+    pub fn new() -> Self {
+        Self {
+            entities: Arc::new(RwLock::new(HashMap::new())),
+        }
+    }
+}
+
+impl<T: MemoryEntity> Repository<T> for InMemoryRepository<T> {
+    async fn create(&self, data: T::Create) -> Result<T> {
+        let entity = T::from_create_data(data)?;
+        let id = entity.id();
+        
+        self.entities.write().await.insert(id, entity.clone());
+        Ok(entity)
+    }
+
+    async fn find_by_id(&self, id: Uuid) -> Result<T> {
+        self.entities
+            .read()
+            .await
+            .get(&id)
+            .cloned()
+            .ok_or_else(|| domain::DomainError::NotFound(format!("{} not found: {}", T::entity_name(), id)))
+    }
+
+    async fn find_all(&self) -> Result<Vec<T>> {
+        Ok(self.entities.read().await.values().cloned().collect())
+    }
+
+    async fn update(&self, id: Uuid, data: T::Update) -> Result<T> {
+        let mut entities = self.entities.write().await;
+        let entity = entities
+            .get_mut(&id)
+            .ok_or_else(|| domain::DomainError::NotFound(format!("{} not found: {}", T::entity_name(), id)))?;
+
+        entity.update(data)?;
+        Ok(entity.clone())
+    }
+
+    async fn delete(&self, id: Uuid) -> Result<()> {
+        self.entities
+            .write()
+            .await
+            .remove(&id)
+            .map(|_| ())
+            .ok_or_else(|| domain::DomainError::NotFound(format!("{} not found: {}", T::entity_name(), id)))
+    }
+}
+
+// Implement MemoryEntity for User
+impl MemoryEntity for User {
+    /// Get the entity's ID
+    fn id(&self) -> Uuid {
+        self.id()
+    }
+    
+    /// Create a new entity from create data
+    fn from_create_data(data: CreateUser) -> Result<Self> {
+        User::new(
+            Uuid::new_v4(),
+            data.username().to_string(),
+            data.email().to_string()
+        )
+    }
+    
+    /// Update the entity with update data
+    fn update(&mut self, data: UpdateUser) -> Result<()> {
+        if let Some(username) = data.username() {
+            self.set_username(username.to_string())?;
+        }
+        if let Some(email) = data.email() {
+            self.set_email(email.to_string())?;
+        }
+        Ok(())
+    }
+    
+    /// Get the entity name for error messages
+    fn entity_name() -> &'static str {
+        "User"
+    }
+}
+
+// Implement MemoryEntity for Product
+impl MemoryEntity for Product {
+    /// Get the entity's ID
+    fn id(&self) -> Uuid {
+        self.id()
+    }
+    
+    /// Create a new entity from create data
+    fn from_create_data(data: CreateProduct) -> Result<Self> {
+        Product::new(
+            Uuid::new_v4(),
+            data.name().to_string(),
+            data.description().to_string()
+        )
+    }
+    
+    /// Update the entity with update data
+    fn update(&mut self, data: UpdateProduct) -> Result<()> {
+        if let Some(name) = data.name() {
+            self.set_name(name.to_string())?;
+        }
+        if let Some(description) = data.description() {
+            self.set_description(description.to_string())?;
+        }
+        Ok(())
+    }
+    
+    /// Get the entity name for error messages
+    fn entity_name() -> &'static str {
+        "Product"
+    }
+}
+
 /// Thread-safe, async in-memory repository for `User` entities.
 ///
 /// Implements all CRUD operations. Intended for testing and non-persistent use cases.
-#[derive(Default, Clone)]
-pub struct InMemoryUserRepository {
-    users: Arc<RwLock<HashMap<Uuid, User>>>,
-}
-
-impl InMemoryUserRepository {
-    pub fn new() -> Self {
-        Self {
-            users: Arc::new(RwLock::new(HashMap::new())),
-        }
-    }
-}
-
-impl Repository<User> for InMemoryUserRepository {
-    async fn create(&self, data: CreateUser) -> Result<User> {
-        let user = User::new(
-            Uuid::new_v4(),
-            data.username().to_string(),
-            data.email().to_string()
-        )?;
-
-        self.users.write().await.insert(user.id(), user.clone());
-        Ok(user)
-    }
-
-    async fn find_by_id(&self, id: Uuid) -> Result<User> {
-        self.users
-            .read()
-            .await
-            .get(&id)
-            .cloned()
-            .ok_or_else(|| domain::DomainError::NotFound(format!("User not found: {}", id)))
-    }
-
-    async fn find_all(&self) -> Result<Vec<User>> {
-        Ok(self.users.read().await.values().cloned().collect())
-    }
-
-    async fn update(&self, id: Uuid, data: UpdateUser) -> Result<User> {
-        let mut users = self.users.write().await;
-        let user = users
-            .get_mut(&id)
-            .ok_or_else(|| domain::DomainError::NotFound(format!("User not found: {}", id)))?;
-
-        if let Some(username) = data.username() {
-            user.set_username(username.to_string())?;
-        }
-        if let Some(email) = data.email() {
-            user.set_email(email.to_string())?;
-        }
-
-        Ok(user.clone())
-    }
-
-    async fn delete(&self, id: Uuid) -> Result<()> {
-        self.users
-            .write()
-            .await
-            .remove(&id)
-            .map(|_| ())
-            .ok_or_else(|| domain::DomainError::NotFound(format!("User not found: {}", id)))
-    }
-}
+pub type InMemoryUserRepository = InMemoryRepository<User>;
 
 /// Thread-safe, async in-memory repository for `Product` entities.
 ///
 /// Implements all CRUD operations. Intended for testing and non-persistent use cases.
-#[derive(Default, Clone)]
-pub struct InMemoryProductRepository {
-    products: Arc<RwLock<HashMap<Uuid, Product>>>,
-}
-
-impl InMemoryProductRepository {
-    pub fn new() -> Self {
-        Self {
-            products: Arc::new(RwLock::new(HashMap::new())),
-        }
-    }
-}
-
-impl Repository<Product> for InMemoryProductRepository {
-    async fn create(&self, data: CreateProduct) -> Result<Product> {
-        let product = Product::new(
-            Uuid::new_v4(),
-            data.name().to_string(),
-            data.description().to_string()
-        )?;
-
-        self.products.write().await.insert(product.id(), product.clone());
-        Ok(product)
-    }
-
-    async fn find_by_id(&self, id: Uuid) -> Result<Product> {
-        self.products
-            .read()
-            .await
-            .get(&id)
-            .cloned()
-            .ok_or_else(|| domain::DomainError::NotFound(format!("Product not found: {}", id)))
-    }
-
-    async fn find_all(&self) -> Result<Vec<Product>> {
-        Ok(self.products.read().await.values().cloned().collect())
-    }
-
-    async fn update(&self, id: Uuid, data: UpdateProduct) -> Result<Product> {
-        let mut products = self.products.write().await;
-        let product = products
-            .get_mut(&id)
-            .ok_or_else(|| domain::DomainError::NotFound(format!("Product not found: {}", id)))?;
-
-        if let Some(name) = data.name() {
-            product.set_name(name.to_string())?;
-        }
-        if let Some(description) = data.description() {
-            product.set_description(description.to_string())?;
-        }
-
-        Ok(product.clone())
-    }
-
-    async fn delete(&self, id: Uuid) -> Result<()> {
-        self.products
-            .write()
-            .await
-            .remove(&id)
-            .map(|_| ())
-            .ok_or_else(|| domain::DomainError::NotFound(format!("Product not found: {}", id)))
-    }
-}
+pub type InMemoryProductRepository = InMemoryRepository<Product>;
 
 /// Type alias for a user service backed by the in-memory repository.
 ///
@@ -181,8 +196,6 @@ pub type MemoryProductService = Service<Product, InMemoryProductRepository>;
 mod tests {
     use super::*;
     use domain::{CreateUser, UpdateUser, CreateProduct, UpdateProduct, DomainError};
-    use std::time::Duration;
-    use tokio::time::sleep;
 
     mod user_repository_tests {
         use super::*;
@@ -198,15 +211,14 @@ mod tests {
             assert_eq!(user.email(), "test@example.com");
             assert!(!user.id().is_nil());
             assert!(user.created_at() <= chrono::Utc::now());
-            assert!(user.updated_at() <= chrono::Utc::now());
         }
 
         #[tokio::test]
         async fn test_find_by_id_existing() {
             let repo = InMemoryUserRepository::new();
             let create_data = CreateUser::new("testuser".to_string(), "test@example.com".to_string()).unwrap();
-
             let created_user = repo.create(create_data).await.unwrap();
+
             let found_user = repo.find_by_id(created_user.id()).await.unwrap();
 
             assert_eq!(found_user.id(), created_user.id());
@@ -220,99 +232,82 @@ mod tests {
             let non_existent_id = Uuid::new_v4();
 
             let result = repo.find_by_id(non_existent_id).await;
+
             assert!(result.is_err());
-            
-            match result.unwrap_err() {
-                DomainError::NotFound(msg) => {
-                    assert!(msg.contains("User not found"));
-                    assert!(msg.contains(&non_existent_id.to_string()));
-                }
-                _ => panic!("Expected NotFound error"),
-            }
+            assert!(matches!(result.unwrap_err(), DomainError::NotFound(_)));
         }
 
         #[tokio::test]
         async fn test_find_all_empty() {
             let repo = InMemoryUserRepository::new();
+
             let users = repo.find_all().await.unwrap();
 
-            assert_eq!(users.len(), 0);
+            assert!(users.is_empty());
         }
 
         #[tokio::test]
         async fn test_find_all_with_users() {
             let repo = InMemoryUserRepository::new();
-            
-            let user1 = repo.create(CreateUser::new("user1".to_string(), "user1@example.com".to_string()).unwrap()).await.unwrap();
+            let create_data1 = CreateUser::new("user1".to_string(), "user1@example.com".to_string()).unwrap();
+            let create_data2 = CreateUser::new("user2".to_string(), "user2@example.com".to_string()).unwrap();
 
-            let user2 = repo.create(CreateUser::new("user2".to_string(), "user2@example.com".to_string()).unwrap()).await.unwrap();
+            repo.create(create_data1).await.unwrap();
+            repo.create(create_data2).await.unwrap();
 
             let users = repo.find_all().await.unwrap();
 
             assert_eq!(users.len(), 2);
-            assert!(users.iter().any(|u| u.id() == user1.id()));
-            assert!(users.iter().any(|u| u.id() == user2.id()));
         }
 
         #[tokio::test]
         async fn test_update_user_existing() {
             let repo = InMemoryUserRepository::new();
-            let user = repo.create(CreateUser::new("olduser".to_string(), "old@example.com".to_string()).unwrap()).await.unwrap();
+            let create_data = CreateUser::new("testuser".to_string(), "test@example.com".to_string()).unwrap();
+            let created_user = repo.create(create_data).await.unwrap();
 
-            let original_updated_at = user.updated_at();
-            sleep(Duration::from_millis(1)).await; // Ensure timestamp difference
+            let update_data = UpdateUser::new(Some("updateduser".to_string()), Some("updated@example.com".to_string())).unwrap();
+            let updated_user = repo.update(created_user.id(), update_data).await.unwrap();
 
-            let update_data = UpdateUser::new(Some("newuser".to_string()), Some("new@example.com".to_string())).unwrap();
-
-            let updated_user = repo.update(user.id(), update_data).await.unwrap();
-
-            assert_eq!(updated_user.username(), "newuser");
-            assert_eq!(updated_user.email(), "new@example.com");
-            assert!(updated_user.updated_at() > original_updated_at);
+            assert_eq!(updated_user.username(), "updateduser");
+            assert_eq!(updated_user.email(), "updated@example.com");
         }
 
         #[tokio::test]
         async fn test_update_user_partial() {
             let repo = InMemoryUserRepository::new();
-            let user = repo.create(CreateUser::new("testuser".to_string(), "test@example.com".to_string()).unwrap()).await.unwrap();
+            let create_data = CreateUser::new("testuser".to_string(), "test@example.com".to_string()).unwrap();
+            let created_user = repo.create(create_data).await.unwrap();
 
-            let update_data = UpdateUser::new(Some("newuser".to_string()), None).unwrap();
+            let update_data = UpdateUser::new(Some("updateduser".to_string()), None).unwrap();
+            let updated_user = repo.update(created_user.id(), update_data).await.unwrap();
 
-            let updated_user = repo.update(user.id(), update_data).await.unwrap();
-
-            assert_eq!(updated_user.username(), "newuser");
-            assert_eq!(updated_user.email(), "test@example.com"); // Should remain unchanged
+            assert_eq!(updated_user.username(), "updateduser");
+            assert_eq!(updated_user.email(), "test@example.com"); // Unchanged
         }
 
         #[tokio::test]
         async fn test_update_user_not_found() {
             let repo = InMemoryUserRepository::new();
             let non_existent_id = Uuid::new_v4();
-            let update_data = UpdateUser::new(Some("newuser".to_string()), None).unwrap();
+            let update_data = UpdateUser::new(Some("updateduser".to_string()), None).unwrap();
 
             let result = repo.update(non_existent_id, update_data).await;
+
             assert!(result.is_err());
-            
-            match result.unwrap_err() {
-                DomainError::NotFound(msg) => {
-                    assert!(msg.contains("User not found"));
-                    assert!(msg.contains(&non_existent_id.to_string()));
-                }
-                _ => panic!("Expected NotFound error"),
-            }
+            assert!(matches!(result.unwrap_err(), DomainError::NotFound(_)));
         }
 
         #[tokio::test]
         async fn test_delete_user_existing() {
             let repo = InMemoryUserRepository::new();
-            let user = repo.create(CreateUser::new("testuser".to_string(), "test@example.com".to_string()).unwrap()).await.unwrap();
+            let create_data = CreateUser::new("testuser".to_string(), "test@example.com".to_string()).unwrap();
+            let created_user = repo.create(create_data).await.unwrap();
+
+            let result = repo.delete(created_user.id()).await;
 
-            let result = repo.delete(user.id()).await;
             assert!(result.is_ok());
-
-            // Verify user is actually deleted
-            let find_result = repo.find_by_id(user.id()).await;
-            assert!(find_result.is_err());
+            assert!(repo.find_all().await.unwrap().is_empty());
         }
 
         #[tokio::test]
@@ -321,15 +316,9 @@ mod tests {
             let non_existent_id = Uuid::new_v4();
 
             let result = repo.delete(non_existent_id).await;
+
             assert!(result.is_err());
-            
-            match result.unwrap_err() {
-                DomainError::NotFound(msg) => {
-                    assert!(msg.contains("User not found"));
-                    assert!(msg.contains(&non_existent_id.to_string()));
-                }
-                _ => panic!("Expected NotFound error"),
-            }
+            assert!(matches!(result.unwrap_err(), DomainError::NotFound(_)));
         }
 
         #[tokio::test]
@@ -337,21 +326,25 @@ mod tests {
             let repo = InMemoryUserRepository::new();
             let repo_clone = repo.clone();
 
-            // Spawn multiple tasks to create users concurrently
-            let handles: Vec<_> = (0..10).map(|i| {
-                let repo = repo_clone.clone();
-                tokio::spawn(async move {
-                    repo.create(CreateUser::new(format!("user{}", i), format!("user{}@example.com", i)).unwrap()).await
+            // Spawn multiple tasks that create users concurrently
+            let handles: Vec<_> = (0..10)
+                .map(|i| {
+                    let repo = repo_clone.clone();
+                    tokio::spawn(async move {
+                        let create_data = CreateUser::new(
+                            format!("user{}", i),
+                            format!("user{}@example.com", i)
+                        ).unwrap();
+                        repo.create(create_data).await
+                    })
                 })
-            }).collect();
+                .collect();
 
             // Wait for all tasks to complete
-            let results = futures::future::join_all(handles).await;
-            for result in results {
-                assert!(result.unwrap().is_ok());
+            for handle in handles {
+                handle.await.unwrap().unwrap();
             }
 
-            // Verify all users were created
             let users = repo.find_all().await.unwrap();
             assert_eq!(users.len(), 10);
         }
@@ -363,23 +356,22 @@ mod tests {
         #[tokio::test]
         async fn test_create_product() {
             let repo = InMemoryProductRepository::new();
-            let create_data = CreateProduct::new("testproduct".to_string(), "test description".to_string()).unwrap();
+            let create_data = CreateProduct::new("testproduct".to_string(), "Test description".to_string()).unwrap();
 
             let product = repo.create(create_data).await.unwrap();
 
             assert_eq!(product.name(), "testproduct");
-            assert_eq!(product.description(), "test description");
+            assert_eq!(product.description(), "Test description");
             assert!(!product.id().is_nil());
             assert!(product.created_at() <= chrono::Utc::now());
-            assert!(product.updated_at() <= chrono::Utc::now());
         }
 
         #[tokio::test]
         async fn test_find_by_id_existing() {
             let repo = InMemoryProductRepository::new();
-            let create_data = CreateProduct::new("testproduct".to_string(), "test description".to_string()).unwrap();
-
+            let create_data = CreateProduct::new("testproduct".to_string(), "Test description".to_string()).unwrap();
             let created_product = repo.create(create_data).await.unwrap();
+
             let found_product = repo.find_by_id(created_product.id()).await.unwrap();
 
             assert_eq!(found_product.id(), created_product.id());
@@ -393,99 +385,82 @@ mod tests {
             let non_existent_id = Uuid::new_v4();
 
             let result = repo.find_by_id(non_existent_id).await;
+
             assert!(result.is_err());
-            
-            match result.unwrap_err() {
-                DomainError::NotFound(msg) => {
-                    assert!(msg.contains("Product not found"));
-                    assert!(msg.contains(&non_existent_id.to_string()));
-                }
-                _ => panic!("Expected NotFound error"),
-            }
+            assert!(matches!(result.unwrap_err(), DomainError::NotFound(_)));
         }
 
         #[tokio::test]
         async fn test_find_all_empty() {
             let repo = InMemoryProductRepository::new();
+
             let products = repo.find_all().await.unwrap();
 
-            assert_eq!(products.len(), 0);
+            assert!(products.is_empty());
         }
 
         #[tokio::test]
         async fn test_find_all_with_products() {
             let repo = InMemoryProductRepository::new();
-            
-            let product1 = repo.create(CreateProduct::new("product1".to_string(), "description1".to_string()).unwrap()).await.unwrap();
+            let create_data1 = CreateProduct::new("product1".to_string(), "Description 1".to_string()).unwrap();
+            let create_data2 = CreateProduct::new("product2".to_string(), "Description 2".to_string()).unwrap();
 
-            let product2 = repo.create(CreateProduct::new("product2".to_string(), "description2".to_string()).unwrap()).await.unwrap();
+            repo.create(create_data1).await.unwrap();
+            repo.create(create_data2).await.unwrap();
 
             let products = repo.find_all().await.unwrap();
 
             assert_eq!(products.len(), 2);
-            assert!(products.iter().any(|p| p.id() == product1.id()));
-            assert!(products.iter().any(|p| p.id() == product2.id()));
         }
 
         #[tokio::test]
         async fn test_update_product_existing() {
             let repo = InMemoryProductRepository::new();
-            let product = repo.create(CreateProduct::new("oldproduct".to_string(), "old description".to_string()).unwrap()).await.unwrap();
+            let create_data = CreateProduct::new("testproduct".to_string(), "Test description".to_string()).unwrap();
+            let created_product = repo.create(create_data).await.unwrap();
 
-            let original_updated_at = product.updated_at();
-            sleep(Duration::from_millis(1)).await; // Ensure timestamp difference
+            let update_data = UpdateProduct::new(Some("updatedproduct".to_string()), Some("Updated description".to_string())).unwrap();
+            let updated_product = repo.update(created_product.id(), update_data).await.unwrap();
 
-            let update_data = UpdateProduct::new(Some("newproduct".to_string()), Some("new description".to_string())).unwrap();
-
-            let updated_product = repo.update(product.id(), update_data).await.unwrap();
-
-            assert_eq!(updated_product.name(), "newproduct");
-            assert_eq!(updated_product.description(), "new description");
-            assert!(updated_product.updated_at() > original_updated_at);
+            assert_eq!(updated_product.name(), "updatedproduct");
+            assert_eq!(updated_product.description(), "Updated description");
         }
 
         #[tokio::test]
         async fn test_update_product_partial() {
             let repo = InMemoryProductRepository::new();
-            let product = repo.create(CreateProduct::new("testproduct".to_string(), "test description".to_string()).unwrap()).await.unwrap();
+            let create_data = CreateProduct::new("testproduct".to_string(), "Test description".to_string()).unwrap();
+            let created_product = repo.create(create_data).await.unwrap();
 
-            let update_data = UpdateProduct::new(Some("newproduct".to_string()), None).unwrap();
+            let update_data = UpdateProduct::new(Some("updatedproduct".to_string()), None).unwrap();
+            let updated_product = repo.update(created_product.id(), update_data).await.unwrap();
 
-            let updated_product = repo.update(product.id(), update_data).await.unwrap();
-
-            assert_eq!(updated_product.name(), "newproduct");
-            assert_eq!(updated_product.description(), "test description"); // Should remain unchanged
+            assert_eq!(updated_product.name(), "updatedproduct");
+            assert_eq!(updated_product.description(), "Test description"); // Unchanged
         }
 
         #[tokio::test]
         async fn test_update_product_not_found() {
             let repo = InMemoryProductRepository::new();
             let non_existent_id = Uuid::new_v4();
-            let update_data = UpdateProduct::new(Some("newproduct".to_string()), None).unwrap();
+            let update_data = UpdateProduct::new(Some("updatedproduct".to_string()), None).unwrap();
 
             let result = repo.update(non_existent_id, update_data).await;
+
             assert!(result.is_err());
-            
-            match result.unwrap_err() {
-                DomainError::NotFound(msg) => {
-                    assert!(msg.contains("Product not found"));
-                    assert!(msg.contains(&non_existent_id.to_string()));
-                }
-                _ => panic!("Expected NotFound error"),
-            }
+            assert!(matches!(result.unwrap_err(), DomainError::NotFound(_)));
         }
 
         #[tokio::test]
         async fn test_delete_product_existing() {
             let repo = InMemoryProductRepository::new();
-            let product = repo.create(CreateProduct::new("testproduct".to_string(), "test description".to_string()).unwrap()).await.unwrap();
+            let create_data = CreateProduct::new("testproduct".to_string(), "Test description".to_string()).unwrap();
+            let created_product = repo.create(create_data).await.unwrap();
+
+            let result = repo.delete(created_product.id()).await;
 
-            let result = repo.delete(product.id()).await;
             assert!(result.is_ok());
-
-            // Verify product is actually deleted
-            let find_result = repo.find_by_id(product.id()).await;
-            assert!(find_result.is_err());
+            assert!(repo.find_all().await.unwrap().is_empty());
         }
 
         #[tokio::test]
@@ -494,111 +469,88 @@ mod tests {
             let non_existent_id = Uuid::new_v4();
 
             let result = repo.delete(non_existent_id).await;
+
             assert!(result.is_err());
-            
-            match result.unwrap_err() {
-                DomainError::NotFound(msg) => {
-                    assert!(msg.contains("Product not found"));
-                    assert!(msg.contains(&non_existent_id.to_string()));
-                }
-                _ => panic!("Expected NotFound error"),
-            }
+            assert!(matches!(result.unwrap_err(), DomainError::NotFound(_)));
         }
 
         #[tokio::test]
         async fn test_concurrent_access() {
             let repo = InMemoryProductRepository::new();
-            let product = repo.create(CreateProduct::new("concurrent_product".to_string(), "concurrent description".to_string()).unwrap()).await.unwrap();
-
-            // Test concurrent access with a simpler approach
             let repo_clone = repo.clone();
-            let product_id = product.id();
-            
-            // Spawn a single concurrent task
-            let handle = tokio::spawn(async move {
-                repo_clone.find_by_id(product_id).await
-            });
 
-            // Direct access
-            let direct_result = repo.find_by_id(product_id).await;
-            let spawned_result = handle.await.unwrap();
+            // Spawn multiple tasks that create products concurrently
+            let handles: Vec<_> = (0..10)
+                .map(|i| {
+                    let repo = repo_clone.clone();
+                    tokio::spawn(async move {
+                        let create_data = CreateProduct::new(
+                            format!("product{}", i),
+                            format!("Description {}", i)
+                        ).unwrap();
+                        repo.create(create_data).await
+                    })
+                })
+                .collect();
 
-            // Both should return the same product
-            assert_eq!(direct_result.unwrap().id(), product_id);
-            assert_eq!(spawned_result.unwrap().id(), product_id);
+            // Wait for all tasks to complete
+            for handle in handles {
+                handle.await.unwrap().unwrap();
+            }
+
+            let products = repo.find_all().await.unwrap();
+            assert_eq!(products.len(), 10);
         }
     }
 
     mod service_tests {
         use super::*;
-        use application::UseCase;
+        use application::UseCase; 
 
         #[tokio::test]
         async fn test_memory_user_service() {
-            let repo = InMemoryUserRepository::new();
-            let service = MemoryUserService::new(repo);
-
-            // Test create
-            let user = service.create(CreateUser::new("testuser".to_string(), "test@example.com".to_string()).unwrap()).await.unwrap();
+            let service = MemoryUserService::new(InMemoryUserRepository::new());
+            let create_data = CreateUser::new("testuser".to_string(), "test@example.com".to_string()).unwrap();
 
+            let user = service.create(create_data).await.unwrap();
             assert_eq!(user.username(), "testuser");
-            assert_eq!(user.email(), "test@example.com");
 
-            // Test get
             let found_user = service.get(user.id()).await.unwrap();
             assert_eq!(found_user.id(), user.id());
 
-            // Test update
-            let updated_user = service.update(user.id(), UpdateUser::new(Some("newuser".to_string()), None).unwrap()).await.unwrap();
-
-            assert_eq!(updated_user.username(), "newuser");
-            assert_eq!(updated_user.email(), "test@example.com");
-
-            // Test list
             let users = service.list().await.unwrap();
             assert_eq!(users.len(), 1);
-            assert_eq!(users[0].id(), user.id());
 
-            // Test delete
+            let update_data = UpdateUser::new(Some("updateduser".to_string()), None).unwrap();
+            let updated_user = service.update(user.id(), update_data).await.unwrap();
+            assert_eq!(updated_user.username(), "updateduser");
+
             service.delete(user.id()).await.unwrap();
-
-            // Verify deletion
-            let result = service.get(user.id()).await;
-            assert!(result.is_err());
+            let users_after_delete = service.list().await.unwrap();
+            assert!(users_after_delete.is_empty());
         }
 
         #[tokio::test]
         async fn test_memory_product_service() {
-            let repo = InMemoryProductRepository::new();
-            let service = MemoryProductService::new(repo);
+            let service = MemoryProductService::new(InMemoryProductRepository::new());
+            let create_data = CreateProduct::new("testproduct".to_string(), "Test description".to_string()).unwrap();
 
-            // Test create
-            let product = service.create(CreateProduct::new("Test Product".to_string(), "Test Description".to_string()).unwrap()).await.unwrap();
+            let product = service.create(create_data).await.unwrap();
+            assert_eq!(product.name(), "testproduct");
 
-            assert_eq!(product.name(), "Test Product");
-            assert_eq!(product.description(), "Test Description");
-
-            // Test get
             let found_product = service.get(product.id()).await.unwrap();
             assert_eq!(found_product.id(), product.id());
 
-            // Test update
-            let updated_product = service.update(product.id(), UpdateProduct::new(Some("New Product".to_string()), None).unwrap()).await.unwrap();
-
-            assert_eq!(updated_product.name(), "New Product");
-            assert_eq!(updated_product.description(), "Test Description");
-
-            // Test list
             let products = service.list().await.unwrap();
             assert_eq!(products.len(), 1);
-            assert_eq!(products[0].id(), product.id());
 
-            // Test delete
+            let update_data = UpdateProduct::new(Some("updatedproduct".to_string()), None).unwrap();
+            let updated_product = service.update(product.id(), update_data).await.unwrap();
+            assert_eq!(updated_product.name(), "updatedproduct");
+
             service.delete(product.id()).await.unwrap();
-
-            // Verify deletion
-            let result = service.get(product.id()).await;
-            assert!(result.is_err());
+            let products_after_delete = service.list().await.unwrap();
+            assert!(products_after_delete.is_empty());
         }
     }
 
@@ -608,57 +560,51 @@ mod tests {
         #[tokio::test]
         async fn test_user_lifecycle() {
             let repo = InMemoryUserRepository::new();
-
-            // Create multiple users
-            let user1 = repo.create(CreateUser::new("user1".to_string(), "user1@example.com".to_string()).unwrap()).await.unwrap();
-
-            let user2 = repo.create(CreateUser::new("user2".to_string(), "user2@example.com".to_string()).unwrap()).await.unwrap();
-
-            // Verify both users exist
-            let users = repo.find_all().await.unwrap();
-            assert_eq!(users.len(), 2);
-
-            // Update one user
-            let updated_user1 = repo.update(user1.id(), UpdateUser::new(Some("updated_user1".to_string()), None).unwrap()).await.unwrap();
-
-            assert_eq!(updated_user1.username(), "updated_user1");
-            assert_eq!(updated_user1.email(), "user1@example.com");
-
-            // Delete one user
-            repo.delete(user2.id()).await.unwrap();
-
-            // Verify only one user remains
-            let remaining_users = repo.find_all().await.unwrap();
-            assert_eq!(remaining_users.len(), 1);
-            assert_eq!(remaining_users[0].id(), user1.id());
+            
+            // Create
+            let create_data = CreateUser::new("testuser".to_string(), "test@example.com".to_string()).unwrap();
+            let user = repo.create(create_data).await.unwrap();
+            assert_eq!(user.username(), "testuser");
+            
+            // Read
+            let found_user = repo.find_by_id(user.id()).await.unwrap();
+            assert_eq!(found_user.id(), user.id());
+            
+            // Update
+            let update_data = UpdateUser::new(Some("updateduser".to_string()), Some("updated@example.com".to_string())).unwrap();
+            let updated_user = repo.update(user.id(), update_data).await.unwrap();
+            assert_eq!(updated_user.username(), "updateduser");
+            assert_eq!(updated_user.email(), "updated@example.com");
+            
+            // Delete
+            repo.delete(user.id()).await.unwrap();
+            let result = repo.find_by_id(user.id()).await;
+            assert!(result.is_err());
         }
 
         #[tokio::test]
         async fn test_product_lifecycle() {
             let repo = InMemoryProductRepository::new();
-
-            // Create multiple products
-            let product1 = repo.create(CreateProduct::new("Product 1".to_string(), "Description 1".to_string()).unwrap()).await.unwrap();
-
-            let product2 = repo.create(CreateProduct::new("Product 2".to_string(), "Description 2".to_string()).unwrap()).await.unwrap();
-
-            // Verify both products exist
-            let products = repo.find_all().await.unwrap();
-            assert_eq!(products.len(), 2);
-
-            // Update one product
-            let updated_product1 = repo.update(product1.id(), UpdateProduct::new(Some("Updated Product 1".to_string()), None).unwrap()).await.unwrap();
-
-            assert_eq!(updated_product1.name(), "Updated Product 1");
-            assert_eq!(updated_product1.description(), "Description 1");
-
-            // Delete one product
-            repo.delete(product2.id()).await.unwrap();
-
-            // Verify only one product remains
-            let remaining_products = repo.find_all().await.unwrap();
-            assert_eq!(remaining_products.len(), 1);
-            assert_eq!(remaining_products[0].id(), product1.id());
+            
+            // Create
+            let create_data = CreateProduct::new("testproduct".to_string(), "Test description".to_string()).unwrap();
+            let product = repo.create(create_data).await.unwrap();
+            assert_eq!(product.name(), "testproduct");
+            
+            // Read
+            let found_product = repo.find_by_id(product.id()).await.unwrap();
+            assert_eq!(found_product.id(), product.id());
+            
+            // Update
+            let update_data = UpdateProduct::new(Some("updatedproduct".to_string()), Some("Updated description".to_string())).unwrap();
+            let updated_product = repo.update(product.id(), update_data).await.unwrap();
+            assert_eq!(updated_product.name(), "updatedproduct");
+            assert_eq!(updated_product.description(), "Updated description");
+            
+            // Delete
+            repo.delete(product.id()).await.unwrap();
+            let result = repo.find_by_id(product.id()).await;
+            assert!(result.is_err());
         }
     }
 }