diff --git a/.editorconfig b/.editorconfig
index a0c05f8..8852f14 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -1,4 +1,7 @@
 [*.cs]
 
 # CS0618: Le type ou le membre est obsolète
-dotnet_diagnostic.CS0618.severity = silent
+dotnet_diagnostic.CS0618.severity = silent
+
+# CS1998: Async method lacks 'await' operators and will run synchronously
+dotnet_diagnostic.CS1998.severity = none
\ No newline at end of file
diff --git a/Controllers/MorePageController.cs b/Controllers/MorePageController.cs
index 5b5fd56..b2ffb52 100644
--- a/Controllers/MorePageController.cs
+++ b/Controllers/MorePageController.cs
@@ -24,14 +24,14 @@ namespace ShoopNCook.Controllers
             app.ForceLogin();
         }
 
-        public void GoToMyRecipesPage()
+        public async void GoToMyRecipesPage()
         {
-            Shell.Current.Navigation.PushAsync(new MyRecipesPage(account, endpoint.RecipesService));
+            await Shell.Current.Navigation.PushAsync(new MyRecipesPage(account, endpoint.RecipesService));
         }
 
-        public void GoToProfilePage()
+        public async void GoToProfilePage()
         {
-            Shell.Current.Navigation.PushAsync(new ProfilePage(account));
+            await Shell.Current.Navigation.PushAsync(new ProfilePage(account));
         }
     }
 }
diff --git a/LocalServices/Data/CatastrophicPerformancesDatabase.cs b/LocalServices/Data/CatastrophicPerformancesDatabase.cs
index 32c48c1..451a424 100644
--- a/LocalServices/Data/CatastrophicPerformancesDatabase.cs
+++ b/LocalServices/Data/CatastrophicPerformancesDatabase.cs
@@ -5,6 +5,8 @@ using System.Collections.Immutable;
 using System.Linq;
 using System.Runtime.Serialization;
 using System.Text;
+using System.Text.Json;
+using System.Text.Json.Serialization;
 using System.Threading.Tasks;
 
 namespace LocalEndpoint.Data
@@ -62,9 +64,11 @@ namespace LocalEndpoint.Data
             Save(ACCOUNTS_FILENAME, ACCOUNTS_SERIALIZER, accountsData);
         }
 
-        public Recipe GetRecipe(Guid id)
+        public Recipe? GetRecipe(Guid id)
         {
-            return ConvertRecipeDataToRecipe(recipesData[id]);
+            if (recipesData.TryGetValue(id, out RecipeData? data))
+                return ConvertRecipeDataToRecipe(data);
+            return null;
         }
 
         public RecipeRate GetRecipeRate(Guid user, Guid recipe)
@@ -72,38 +76,38 @@ namespace LocalEndpoint.Data
             return usersData[user].Rates[recipe];
         }
 
-        public void InsertInUserList(Guid userId, Guid recipeId, uint persAmount)
+        public async void InsertInUserList(Guid userId, Guid recipeId, uint persAmount)
         {
             usersData[userId].RecipesList[recipeId] = persAmount;
             Save(USERS_FILENAME, USERS_SERIALIZER, usersData);
         }
 
-        public void RemoveFromUserList(Guid userId, Guid recipeId)
+        public async void RemoveFromUserList(Guid userId, Guid recipeId)
         {
             usersData[userId].RecipesList.Remove(recipeId);
             Save(USERS_FILENAME, USERS_SERIALIZER, usersData);
         }
 
 
-        public void InsertRecipe(Recipe recipe)
+        public async void InsertRecipe(Recipe recipe)
         {
             recipesData[recipe.Info.Id] = new RecipeData(recipe.Info, recipe.Owner.Id, recipe.Ingredients, recipe.Steps);
             Save(RECIPES_FILENAME, RECIPES_SERIALIZER, recipesData);
         }
 
-        public void InsertUser(User user)
+        public async void InsertUser(User user)
         {
             usersData[user.Id] = new UserData(user, new Dictionary<Guid, RecipeRate>(), new Dictionary<Guid, uint>());
             Save(USERS_FILENAME, USERS_SERIALIZER, usersData);
         }
 
-        public void InsertRate(Guid userId, Guid recipeId, RecipeRate rate)
+        public async void InsertRate(Guid userId, Guid recipeId, RecipeRate rate)
         {
             usersData[userId].Rates[recipeId] = rate;
             Save(USERS_FILENAME, USERS_SERIALIZER, usersData);
         }
 
-        public void RemoveRecipe(Guid id)
+        public async void RemoveRecipe(Guid id)
         {
             recipesData.Remove(id);
             Save(RECIPES_FILENAME, RECIPES_SERIALIZER, recipesData);
@@ -141,19 +145,16 @@ namespace LocalEndpoint.Data
 
             if (fileInfo.Length == 0)
                 return new Dictionary<K, V>(); //file is empty thus there is nothing to deserialize
-            Console.WriteLine(File.ReadAllText(file));
 
-            using (var stream = File.OpenRead(file))
-                return deserializer.ReadObject(stream) as Dictionary<K, V> ?? throw new Exception("object read from " + file + " is not a dictionnary");
+            string text = File.ReadAllText(file);
+
+            return JsonSerializer.Deserialize<Dictionary<K, V>>(text);
         }
 
-        private void Save<K, T>(string fileName, DataContractSerializer serializer, Dictionary<K, T> dict)
+        private async void Save<K, T>(string fileName, DataContractSerializer serializer, Dictionary<K, T> dict)
         {
-            using (var stream = File.OpenWrite(dbPath + "/" + fileName))
-            {
-                serializer.WriteObject(stream, dict);
-                stream.Flush();
-            }
+            string json = JsonSerializer.Serialize(dict);
+            File.WriteAllText(dbPath + "/" + fileName, json);
         }
 
     }
diff --git a/LocalServices/Data/Database.cs b/LocalServices/Data/Database.cs
index 130093a..03f3975 100644
--- a/LocalServices/Data/Database.cs
+++ b/LocalServices/Data/Database.cs
@@ -9,7 +9,7 @@ namespace LocalEndpoint.Data
     public interface Database
     {
 
-        public Recipe GetRecipe(Guid id);
+        public Recipe? GetRecipe(Guid id);
 
         public RecipeRate GetRecipeRate(Guid user, Guid recipe);
 
diff --git a/LocalServices/RecipesService.cs b/LocalServices/RecipesService.cs
index 8969e9e..f47b19e 100644
--- a/LocalServices/RecipesService.cs
+++ b/LocalServices/RecipesService.cs
@@ -21,7 +21,7 @@ namespace LocalEndpoint
             return db.ListAllRecipes().Take(4).ToImmutableList().ConvertAll(v => v.Info);
         }
 
-        public Recipe GetRecipe(RecipeInfo info)
+        public Recipe? GetRecipe(RecipeInfo info)
         {
             return db.GetRecipe(info.Id);
         }
diff --git a/Services/IRecipesService.cs b/Services/IRecipesService.cs
index 88e8b65..232da18 100644
--- a/Services/IRecipesService.cs
+++ b/Services/IRecipesService.cs
@@ -8,7 +8,7 @@ namespace Endpoint
     {
         public ImmutableList<RecipeInfo> PopularRecipes();
 
-        public Recipe GetRecipe(RecipeInfo info);
+        public Recipe? GetRecipe(RecipeInfo info);
 
         public IAccountOwnedRecipes GetRecipesOf(Account account);
         public IAccountRecipesPreferences GetPreferencesOf(Account account);
diff --git a/Views/ConfirmMail.xaml b/Views/ConfirmMail.xaml
index ae22bca..a4458ea 100644
--- a/Views/ConfirmMail.xaml
+++ b/Views/ConfirmMail.xaml
@@ -37,11 +37,9 @@
             <!-- Email entry -->
             <Grid
                 Grid.Row="1"
-                RowDefinitions="*, Auto, Auto"
-                >
+                RowDefinitions="*, Auto, Auto">
 
                 <Label 
-                    
                     Grid.Row="0"
                     FontSize="15"
                     TextColor="{StaticResource TextColorSecondary}"
diff --git a/Views/CreateRecipePage.xaml.cs b/Views/CreateRecipePage.xaml.cs
index f6f468d..f39d3f7 100644
--- a/Views/CreateRecipePage.xaml.cs
+++ b/Views/CreateRecipePage.xaml.cs
@@ -16,21 +16,21 @@ public partial class CreateRecipePage : ContentPage
         this.onRecipeCreated = onRecipeCreated;
 	}
 
-    private void OnAddIngredientTapped(object sender, TappedEventArgs e)
+    private async void OnAddIngredientTapped(object sender, TappedEventArgs e)
     {
         IngredientList.Children.Add(new IngredientEntry());
     }
 
-    private void OnAddStepTapped(object sender, TappedEventArgs e)
+    private async void OnAddStepTapped(object sender, TappedEventArgs e)
     {
         StepList.Children.Add(new StepEntry((uint) StepList.Children.Count() + 1));
     }
-    private void OnBackButtonClicked(object sender, EventArgs e)
+    private async void OnBackButtonClicked(object sender, EventArgs e)
     {
         Navigation.PopAsync();
     }
 
-    private void OnUploadRecipeClicked(object sender, EventArgs e)
+    private async void OnUploadRecipeClicked(object sender, EventArgs e)
     {
 
         uint callPerPers;
diff --git a/Views/FavoritesPage.xaml.cs b/Views/FavoritesPage.xaml.cs
index a02523e..4bdda6e 100644
--- a/Views/FavoritesPage.xaml.cs
+++ b/Views/FavoritesPage.xaml.cs
@@ -27,15 +27,15 @@ public partial class FavoritesPage : ContentPage
         RecipeViewLayout.Children.Clear();
         preferences.GetFavorites().ForEach(info =>
         {
-            RecipeViewLayout.Children.Add(new RecipeView(info, () =>
+            RecipeViewLayout.Children.Add(new RecipeView(info, async () =>
             {
-                Recipe recipe = service.GetRecipe(info);
-                Shell.Current.Navigation.PushAsync(new RecipePage(recipe, preferences, 1));
+                Recipe? recipe = service.GetRecipe(info);
+                await Shell.Current.Navigation.PushAsync(new RecipePage(recipe, preferences, 1));
             }));
         });
     }
 
-    private void ContentPage_NavigatedTo(object sender, NavigatedToEventArgs e)
+    private async void ContentPage_NavigatedTo(object sender, NavigatedToEventArgs e)
     {
         UpdateFavorites();
     }
diff --git a/Views/HomePage.xaml.cs b/Views/HomePage.xaml.cs
index 333b718..f38fb0f 100644
--- a/Views/HomePage.xaml.cs
+++ b/Views/HomePage.xaml.cs
@@ -1,42 +1,46 @@
-
-namespace ShoopNCook.Pages;
-using Models;
-using ShoopNCook.Views;
-using Endpoint;
-using LocalEndpoint;
-
-public partial class HomePage : ContentPage
-{
-	public HomePage(Account account, IEndpoint endpoint)
-    {
-		InitializeComponent();
-
-        IRecipesService service = endpoint.RecipesService;
-        IAccountRecipesPreferences preferences = service.GetPreferencesOf(account);
-
-
-        //TODO this code can be factorised
-        void PushRecipe(Layout layout, RecipeInfo info)
-        {
-            layout.Children.Add(new RecipeView(info, () =>
-            {
-                Recipe recipe = service.GetRecipe(info);
-                Shell.Current.Navigation.PushAsync(new RecipePage(recipe, preferences, 1));
-            }));
-        }
-
-        service.PopularRecipes().ForEach(recipe => PushRecipe(PopularsList, recipe));
-        preferences.GetRecommendedRecipes().ForEach(recipe => PushRecipe(RecommendedList, recipe));
-
-        ProfilePictureImage.Source = ImageSource.FromUri(account.User.ProfilePicture);
-        ProfilePictureName.Text = account.User.Name;
-	}
-
-
-    
-
-    private void OnSyncButtonClicked(object sender, EventArgs e)
-    {
-        Shell.Current.Navigation.PushAsync(new SearchPage());
-    }
+namespace ShoopNCook.Pages;
+using Models;
+using ShoopNCook.Views;
+using Endpoint;
+using LocalEndpoint;
+
+public partial class HomePage : ContentPage
+{
+	public HomePage(Account account, IEndpoint endpoint)
+    {
+		InitializeComponent();
+
+        IRecipesService service = endpoint.RecipesService;
+        IAccountRecipesPreferences preferences = service.GetPreferencesOf(account);
+
+
+        //TODO this code can be factorised
+        void PushRecipe(Layout layout, RecipeInfo info)
+        {
+            layout.Children.Add(new RecipeView(info, () =>
+            {
+                Recipe? recipe = service.GetRecipe(info);
+                if (recipe != null)
+                    Shell.Current.Navigation.PushAsync(new RecipePage(recipe, preferences, 1));
+                else
+                {
+                    UserNotifier.Error("Could not find recipe");
+                }
+            }));
+        }
+
+        service.PopularRecipes().ForEach(recipe => PushRecipe(PopularsList, recipe));
+        preferences.GetRecommendedRecipes().ForEach(recipe => PushRecipe(RecommendedList, recipe));
+
+        ProfilePictureImage.Source = ImageSource.FromUri(account.User.ProfilePicture);
+        ProfilePictureName.Text = account.User.Name;
+	}
+
+
+    
+
+    private async void OnSyncButtonClicked(object sender, EventArgs e)
+    {
+        await Shell.Current.Navigation.PushAsync(new SearchPage());
+    }
 }
\ No newline at end of file
diff --git a/Views/MyListPage.xaml.cs b/Views/MyListPage.xaml.cs
index f6f8f08..7adabd1 100644
--- a/Views/MyListPage.xaml.cs
+++ b/Views/MyListPage.xaml.cs
@@ -35,7 +35,7 @@ public partial class MyListPage : ContentPage
         });
     }
 
-    private void ContentPage_NavigatedTo(object sender, NavigatedToEventArgs e)
+    private async void ContentPage_NavigatedTo(object sender, NavigatedToEventArgs e)
     {
         UpdateMyList();
     }
diff --git a/Views/MyRecipesPage.xaml.cs b/Views/MyRecipesPage.xaml.cs
index 78bcc85..bdfb844 100644
--- a/Views/MyRecipesPage.xaml.cs
+++ b/Views/MyRecipesPage.xaml.cs
@@ -58,11 +58,11 @@ public partial class MyRecipesPage : ContentPage
         UserNotifier.Success("Recipe successfully removed");
     }
 
-    private void OnBackButtonClicked(object sender, EventArgs e)
+    private async void OnBackButtonClicked(object sender, EventArgs e)
     {
-        Navigation.PopAsync();
+        await Navigation.PopAsync();
     }
-    private void OnAddRecipeButtonClicked(object sender, EventArgs e)
+    private async void OnAddRecipeButtonClicked(object sender, EventArgs e)
     {
         IAccountOwnedRecipes recipes = service.GetRecipesOf(account);
 
diff --git a/Views/RecipePage.xaml.cs b/Views/RecipePage.xaml.cs
index 583fa33..d8fbe39 100644
--- a/Views/RecipePage.xaml.cs
+++ b/Views/RecipePage.xaml.cs
@@ -75,7 +75,7 @@ public partial class RecipePage : ContentPage
         }
     }
 
-    private void OnFavorite(object o, EventArgs e)
+    private async void OnFavorite(object o, EventArgs e)
     {
         SetFavorite(!isFavorite);
         if (isFavorite)
@@ -84,13 +84,13 @@ public partial class RecipePage : ContentPage
             preferences.RemoveFromFavorites(info);
     }
 
-    private void OnSubmitReviewClicked(object o, EventArgs e)
+    private async void OnSubmitReviewClicked(object o, EventArgs e)
     {
         preferences.SetReviewScore(info, note);
         UserNotifier.Success("Your review has been successfuly submited");
     }
 
-    private void OnAddToMyListClicked(object o, EventArgs e)
+    private async void OnAddToMyListClicked(object o, EventArgs e)
     {
         if (!preferences.AddToWeeklyList(info, Counter.Count))
             UserNotifier.Notice("You already added this recipe to you weekly list!");
@@ -106,9 +106,9 @@ public partial class RecipePage : ContentPage
         else
             Favorite.Source = ImageSource.FromFile("hearth_off.svg");
     }
-    private void OnBackButtonClicked(object sender, EventArgs e)
+    private async void OnBackButtonClicked(object sender, EventArgs e)
     {
-        Navigation.PopAsync();
+        await Navigation.PopAsync();
     }
 
 }
\ No newline at end of file
diff --git a/Views/RegisterPage.xaml.cs b/Views/RegisterPage.xaml.cs
index b8d1929..65c3b2c 100644
--- a/Views/RegisterPage.xaml.cs
+++ b/Views/RegisterPage.xaml.cs
@@ -14,7 +14,7 @@ public partial class RegisterPage : ContentPage
     {
         await Shell.Current.GoToAsync("//Login");
     }
-    private void RegisterTapped(object sender, EventArgs e)
+    private async void RegisterTapped(object sender, EventArgs e)
     {
         string email = EmailEntry.Text;
         string password = PasswordEntry.Text;
diff --git a/documentation/.ShopNCookUML.vpp.lck b/documentation/.ShopNCookUML.vpp.lck
new file mode 100644
index 0000000..e69de29
diff --git a/documentation/ShopNCookUML.vpp b/documentation/ShopNCookUML.vpp
new file mode 100644
index 0000000..3848217
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diff --git a/documentation/ShopNCookUML.vpp.bak_000f b/documentation/ShopNCookUML.vpp.bak_000f
new file mode 100644
index 0000000..3848217
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