diff --git a/Francesco.Recipes.World/Models/BackendModels/Ingredient/Ingredient.cs b/Francesco.Recipes.World/Models/BackendModels/Ingredient/Ingredient.cs
index 291da18..f8bf8eb 100644
--- a/Francesco.Recipes.World/Models/BackendModels/Ingredient/Ingredient.cs
+++ b/Francesco.Recipes.World/Models/BackendModels/Ingredient/Ingredient.cs
@@ -7,7 +7,7 @@
     public class Ingredient
     {
         public Guid Id { get; set; }
-        public string? Name { get; set; }
+        public string Name { get; set; }
         public virtual ICollection<RecipeIngredient> RecipeIngredients { get; set; } = new List<RecipeIngredient>();
         public virtual ICollection<IngredientsShoppingList> IngredientShoppingLists { get; set; } = new List<IngredientsShoppingList>();
     }
diff --git a/Francesco.Recipes.World/Models/BackendModels/Instruction/Instruction.cs b/Francesco.Recipes.World/Models/BackendModels/Instruction/Instruction.cs
index fc14bd6..6f0919c 100644
--- a/Francesco.Recipes.World/Models/BackendModels/Instruction/Instruction.cs
+++ b/Francesco.Recipes.World/Models/BackendModels/Instruction/Instruction.cs
@@ -5,8 +5,8 @@
     public class Instruction
     {
         public Guid Id { get; set; }
-        public string? Description { get; set; }
-        public string? Number { get; set; }
+        public string Description { get; set; }
+        public string Number { get; set; }
         public virtual Recipe Recipe { get; set; } = new();
         public virtual ICollection<MediaFile> MediaFiles { get; set; } = new List<MediaFile>();
     }
diff --git a/Francesco.Recipes.World/Models/BackendModels/Recipe/Recipe.cs b/Francesco.Recipes.World/Models/BackendModels/Recipe/Recipe.cs
index 6c352a5..68d180c 100644
--- a/Francesco.Recipes.World/Models/BackendModels/Recipe/Recipe.cs
+++ b/Francesco.Recipes.World/Models/BackendModels/Recipe/Recipe.cs
@@ -6,10 +6,10 @@
     using Francesco.Recipes.World.Models.BackendModels.MediaFile;
     using Francesco.Recipes.World.Models.BackendModels.RecipeIngredient;
 
-    public class Recipe
+    public class Recipe : ITimeStampedEntity
     {
         public Guid Id { get; set; }
-        public string? Name { get; set; }
+        public string Name { get; set; }
         public string? Description { get; set; }
         public Difficulty Difficulty { get; set; }
         public int Servings { get; set; }
@@ -17,9 +17,9 @@
         public TimeSpan CookingTime { get; set; }
         public bool IsFavorite { get; set; }
         public DateTime CreatedAt { get; set; }
+        public DateTime? ModifiedAt { get; set; }
         public virtual ICollection<RecipeIngredient> RecipeIngredients { get; set; } = new List<RecipeIngredient>();
         public virtual ICollection<Instruction> Instructions { get; set; } = new List<Instruction>();
         public virtual ICollection<MediaFile> MediaFiles { get; set; } = new List<MediaFile>();
         public virtual Favorit Favorit { get; set; } = new();
     }
-}
diff --git a/Francesco.Recipes.World/Models/BackendModels/Shoppinglist/ShoppingList.cs b/Francesco.Recipes.World/Models/BackendModels/Shoppinglist/ShoppingList.cs
index bcb1629..a6f764e 100644
--- a/Francesco.Recipes.World/Models/BackendModels/Shoppinglist/ShoppingList.cs
+++ b/Francesco.Recipes.World/Models/BackendModels/Shoppinglist/ShoppingList.cs
@@ -2,10 +2,11 @@
 
 namespace Francesco.Recipes.World.Models.BackendModels.Shoppinglist
 {
-    public class ShoppingList
+    public class ShoppingList : ITimeStampedEntity
     {
         public Guid Id { get; set; }
         public DateTime CreatedAt { get; set; }
+        public DateTime? ModifiedAt { get; set; }
         public virtual ICollection<IngredientsShoppingList> IngredientsShoppingLists { get; set; } = new List<IngredientsShoppingList>();
     }
 }