diff --git a/src/config/queryKeys.ts b/src/config/queryKeys.ts
new file mode 100644
index 00000000..dbe3a8b5
--- /dev/null
+++ b/src/config/queryKeys.ts
@@ -0,0 +1,84 @@
+// src/config/queryKeys.ts
+/**
+ * Centralized query keys for TanStack Query.
+ *
+ * This file provides a single source of truth for all query keys used
+ * throughout the application. Using these factory functions ensures
+ * consistent key naming and proper cache invalidation.
+ *
+ * @example
+ * ```tsx
+ * // In a query hook
+ * useQuery({
+ *   queryKey: queryKeys.flyers(10, 0),
+ *   queryFn: fetchFlyers,
+ * });
+ *
+ * // For cache invalidation
+ * queryClient.invalidateQueries({ queryKey: queryKeys.watchedItems() });
+ * ```
+ */
+export const queryKeys = {
+  // User Features
+  flyers: (limit: number, offset: number) => ['flyers', { limit, offset }] as const,
+  flyerItems: (flyerId: number) => ['flyer-items', flyerId] as const,
+  flyerItemsBatch: (flyerIds: number[]) =>
+    ['flyer-items-batch', flyerIds.sort().join(',')] as const,
+  flyerItemsCount: (flyerIds: number[]) =>
+    ['flyer-items-count', flyerIds.sort().join(',')] as const,
+  masterItems: () => ['master-items'] as const,
+  watchedItems: () => ['watched-items'] as const,
+  shoppingLists: () => ['shopping-lists'] as const,
+
+  // Auth & Profile
+  authProfile: () => ['auth-profile'] as const,
+  userAddress: (addressId: number | null) => ['user-address', addressId] as const,
+  userProfileData: () => ['user-profile-data'] as const,
+
+  // Admin Features
+  activityLog: (limit: number, offset: number) => ['activity-log', { limit, offset }] as const,
+  applicationStats: () => ['application-stats'] as const,
+  suggestedCorrections: () => ['suggested-corrections'] as const,
+  categories: () => ['categories'] as const,
+
+  // Analytics
+  bestSalePrices: () => ['best-sale-prices'] as const,
+  priceHistory: (masterItemIds: number[]) =>
+    ['price-history', [...masterItemIds].sort((a, b) => a - b).join(',')] as const,
+  leaderboard: (limit: number) => ['leaderboard', limit] as const,
+} as const;
+
+/**
+ * Base keys for partial matching in cache invalidation.
+ *
+ * Use these when you need to invalidate all queries of a certain type
+ * regardless of their parameters.
+ *
+ * @example
+ * ```tsx
+ * // Invalidate all flyer-related queries
+ * queryClient.invalidateQueries({ queryKey: queryKeyBases.flyers });
+ * ```
+ */
+export const queryKeyBases = {
+  flyers: ['flyers'] as const,
+  flyerItems: ['flyer-items'] as const,
+  flyerItemsBatch: ['flyer-items-batch'] as const,
+  flyerItemsCount: ['flyer-items-count'] as const,
+  masterItems: ['master-items'] as const,
+  watchedItems: ['watched-items'] as const,
+  shoppingLists: ['shopping-lists'] as const,
+  authProfile: ['auth-profile'] as const,
+  userAddress: ['user-address'] as const,
+  userProfileData: ['user-profile-data'] as const,
+  activityLog: ['activity-log'] as const,
+  applicationStats: ['application-stats'] as const,
+  suggestedCorrections: ['suggested-corrections'] as const,
+  categories: ['categories'] as const,
+  bestSalePrices: ['best-sale-prices'] as const,
+  priceHistory: ['price-history'] as const,
+  leaderboard: ['leaderboard'] as const,
+} as const;
+
+export type QueryKeys = typeof queryKeys;
+export type QueryKeyBases = typeof queryKeyBases;
diff --git a/src/hooks/mutations/useAddShoppingListItemMutation.ts b/src/hooks/mutations/useAddShoppingListItemMutation.ts
index 44e6bdfc..4ab0270e 100644
--- a/src/hooks/mutations/useAddShoppingListItemMutation.ts
+++ b/src/hooks/mutations/useAddShoppingListItemMutation.ts
@@ -2,6 +2,7 @@
 import { useMutation, useQueryClient } from '@tanstack/react-query';
 import * as apiClient from '../../services/apiClient';
 import { notifySuccess, notifyError } from '../../services/notificationService';
+import { queryKeyBases } from '../../config/queryKeys';
 
 interface AddShoppingListItemParams {
   listId: number;
@@ -61,7 +62,7 @@ export const useAddShoppingListItemMutation = () => {
     },
     onSuccess: () => {
       // Invalidate and refetch shopping lists to get the updated list
-      queryClient.invalidateQueries({ queryKey: ['shopping-lists'] });
+      queryClient.invalidateQueries({ queryKey: queryKeyBases.shoppingLists });
       notifySuccess('Item added to shopping list');
     },
     onError: (error: Error) => {
diff --git a/src/hooks/mutations/useAddWatchedItemMutation.ts b/src/hooks/mutations/useAddWatchedItemMutation.ts
index b6934a9e..f52a0352 100644
--- a/src/hooks/mutations/useAddWatchedItemMutation.ts
+++ b/src/hooks/mutations/useAddWatchedItemMutation.ts
@@ -2,6 +2,7 @@
 import { useMutation, useQueryClient } from '@tanstack/react-query';
 import * as apiClient from '../../services/apiClient';
 import { notifySuccess, notifyError } from '../../services/notificationService';
+import { queryKeyBases } from '../../config/queryKeys';
 
 interface AddWatchedItemParams {
   itemName: string;
@@ -50,7 +51,7 @@ export const useAddWatchedItemMutation = () => {
     },
     onSuccess: () => {
       // Invalidate and refetch watched items to get the updated list
-      queryClient.invalidateQueries({ queryKey: ['watched-items'] });
+      queryClient.invalidateQueries({ queryKey: queryKeyBases.watchedItems });
       notifySuccess('Item added to watched list');
     },
     onError: (error: Error) => {
diff --git a/src/hooks/mutations/useAuthMutations.ts b/src/hooks/mutations/useAuthMutations.ts
new file mode 100644
index 00000000..1e73ce5b
--- /dev/null
+++ b/src/hooks/mutations/useAuthMutations.ts
@@ -0,0 +1,113 @@
+// src/hooks/mutations/useAuthMutations.ts
+import { useMutation } from '@tanstack/react-query';
+import * as apiClient from '../../services/apiClient';
+import { notifyError } from '../../services/notificationService';
+import type { UserProfile } from '../../types';
+
+interface AuthResponse {
+  userprofile: UserProfile;
+  token: string;
+}
+
+/**
+ * Mutation hook for user login.
+ *
+ * @example
+ * ```tsx
+ * const loginMutation = useLoginMutation();
+ * loginMutation.mutate({ email, password, rememberMe });
+ * ```
+ */
+export const useLoginMutation = () => {
+  return useMutation({
+    mutationFn: async ({
+      email,
+      password,
+      rememberMe,
+    }: {
+      email: string;
+      password: string;
+      rememberMe: boolean;
+    }): Promise<AuthResponse> => {
+      const response = await apiClient.loginUser(email, password, rememberMe);
+
+      if (!response.ok) {
+        const error = await response.json().catch(() => ({
+          message: `Request failed with status ${response.status}`,
+        }));
+        throw new Error(error.message || 'Failed to login');
+      }
+
+      return response.json();
+    },
+    onError: (error: Error) => {
+      notifyError(error.message || 'Failed to login');
+    },
+  });
+};
+
+/**
+ * Mutation hook for user registration.
+ *
+ * @example
+ * ```tsx
+ * const registerMutation = useRegisterMutation();
+ * registerMutation.mutate({ email, password, fullName });
+ * ```
+ */
+export const useRegisterMutation = () => {
+  return useMutation({
+    mutationFn: async ({
+      email,
+      password,
+      fullName,
+    }: {
+      email: string;
+      password: string;
+      fullName: string;
+    }): Promise<AuthResponse> => {
+      const response = await apiClient.registerUser(email, password, fullName, '');
+
+      if (!response.ok) {
+        const error = await response.json().catch(() => ({
+          message: `Request failed with status ${response.status}`,
+        }));
+        throw new Error(error.message || 'Failed to register');
+      }
+
+      return response.json();
+    },
+    onError: (error: Error) => {
+      notifyError(error.message || 'Failed to register');
+    },
+  });
+};
+
+/**
+ * Mutation hook for requesting a password reset.
+ *
+ * @example
+ * ```tsx
+ * const passwordResetMutation = usePasswordResetRequestMutation();
+ * passwordResetMutation.mutate({ email });
+ * ```
+ */
+export const usePasswordResetRequestMutation = () => {
+  return useMutation({
+    mutationFn: async ({ email }: { email: string }): Promise<{ message: string }> => {
+      const response = await apiClient.requestPasswordReset(email);
+
+      if (!response.ok) {
+        const error = await response.json().catch(() => ({
+          message: `Request failed with status ${response.status}`,
+        }));
+        throw new Error(error.message || 'Failed to request password reset');
+      }
+
+      return response.json();
+    },
+    onError: (error: Error) => {
+      notifyError(error.message || 'Failed to request password reset');
+    },
+  });
+};
diff --git a/src/hooks/mutations/useCreateShoppingListMutation.ts b/src/hooks/mutations/useCreateShoppingListMutation.ts
index 67522c7d..33626f4c 100644
--- a/src/hooks/mutations/useCreateShoppingListMutation.ts
+++ b/src/hooks/mutations/useCreateShoppingListMutation.ts
@@ -2,6 +2,7 @@
 import { useMutation, useQueryClient } from '@tanstack/react-query';
 import * as apiClient from '../../services/apiClient';
 import { notifySuccess, notifyError } from '../../services/notificationService';
+import { queryKeyBases } from '../../config/queryKeys';
 
 interface CreateShoppingListParams {
   name: string;
@@ -48,7 +49,7 @@ export const useCreateShoppingListMutation = () => {
     },
     onSuccess: () => {
       // Invalidate and refetch shopping lists to get the updated list
-      queryClient.invalidateQueries({ queryKey: ['shopping-lists'] });
+      queryClient.invalidateQueries({ queryKey: queryKeyBases.shoppingLists });
       notifySuccess('Shopping list created');
     },
     onError: (error: Error) => {
diff --git a/src/hooks/mutations/useDeleteShoppingListMutation.ts b/src/hooks/mutations/useDeleteShoppingListMutation.ts
index 4c5f1f08..825ddaa4 100644
--- a/src/hooks/mutations/useDeleteShoppingListMutation.ts
+++ b/src/hooks/mutations/useDeleteShoppingListMutation.ts
@@ -2,6 +2,7 @@
 import { useMutation, useQueryClient } from '@tanstack/react-query';
 import * as apiClient from '../../services/apiClient';
 import { notifySuccess, notifyError } from '../../services/notificationService';
+import { queryKeyBases } from '../../config/queryKeys';
 
 interface DeleteShoppingListParams {
   listId: number;
@@ -48,7 +49,7 @@ export const useDeleteShoppingListMutation = () => {
     },
     onSuccess: () => {
       // Invalidate and refetch shopping lists to get the updated list
-      queryClient.invalidateQueries({ queryKey: ['shopping-lists'] });
+      queryClient.invalidateQueries({ queryKey: queryKeyBases.shoppingLists });
       notifySuccess('Shopping list deleted');
     },
     onError: (error: Error) => {
diff --git a/src/hooks/mutations/useProfileMutations.ts b/src/hooks/mutations/useProfileMutations.ts
new file mode 100644
index 00000000..0d6be202
--- /dev/null
+++ b/src/hooks/mutations/useProfileMutations.ts
@@ -0,0 +1,179 @@
+// src/hooks/mutations/useProfileMutations.ts
+import { useMutation } from '@tanstack/react-query';
+import * as apiClient from '../../services/apiClient';
+import { notifyError } from '../../services/notificationService';
+import type { Profile, Address } from '../../types';
+
+/**
+ * Mutation hook for updating user profile.
+ *
+ * @example
+ * ```tsx
+ * const updateProfile = useUpdateProfileMutation();
+ * updateProfile.mutate({ full_name: 'New Name', avatar_url: 'https://...' });
+ * ```
+ */
+export const useUpdateProfileMutation = () => {
+  return useMutation({
+    mutationFn: async (data: Partial<Profile>): Promise<Profile> => {
+      const response = await apiClient.updateUserProfile(data);
+
+      if (!response.ok) {
+        const error = await response.json().catch(() => ({
+          message: `Request failed with status ${response.status}`,
+        }));
+        throw new Error(error.message || 'Failed to update profile');
+      }
+
+      return response.json();
+    },
+    onError: (error: Error) => {
+      notifyError(error.message || 'Failed to update profile');
+    },
+  });
+};
+
+/**
+ * Mutation hook for updating user address.
+ *
+ * @example
+ * ```tsx
+ * const updateAddress = useUpdateAddressMutation();
+ * updateAddress.mutate({ street_address: '123 Main St', city: 'Toronto' });
+ * ```
+ */
+export const useUpdateAddressMutation = () => {
+  return useMutation({
+    mutationFn: async (data: Partial<Address>): Promise<Address> => {
+      const response = await apiClient.updateUserAddress(data);
+
+      if (!response.ok) {
+        const error = await response.json().catch(() => ({
+          message: `Request failed with status ${response.status}`,
+        }));
+        throw new Error(error.message || 'Failed to update address');
+      }
+
+      return response.json();
+    },
+    onError: (error: Error) => {
+      notifyError(error.message || 'Failed to update address');
+    },
+  });
+};
+
+/**
+ * Mutation hook for updating user password.
+ *
+ * @example
+ * ```tsx
+ * const updatePassword = useUpdatePasswordMutation();
+ * updatePassword.mutate({ password: 'newPassword123' });
+ * ```
+ */
+export const useUpdatePasswordMutation = () => {
+  return useMutation({
+    mutationFn: async ({ password }: { password: string }): Promise<void> => {
+      const response = await apiClient.updateUserPassword(password);
+
+      if (!response.ok) {
+        const error = await response.json().catch(() => ({
+          message: `Request failed with status ${response.status}`,
+        }));
+        throw new Error(error.message || 'Failed to update password');
+      }
+
+      return response.json();
+    },
+    onError: (error: Error) => {
+      notifyError(error.message || 'Failed to update password');
+    },
+  });
+};
+
+/**
+ * Mutation hook for updating user preferences.
+ *
+ * @example
+ * ```tsx
+ * const updatePreferences = useUpdatePreferencesMutation();
+ * updatePreferences.mutate({ darkMode: true });
+ * ```
+ */
+export const useUpdatePreferencesMutation = () => {
+  return useMutation({
+    mutationFn: async (prefs: Partial<Profile['preferences']>): Promise<Profile> => {
+      const response = await apiClient.updateUserPreferences(prefs);
+
+      if (!response.ok) {
+        const error = await response.json().catch(() => ({
+          message: `Request failed with status ${response.status}`,
+        }));
+        throw new Error(error.message || 'Failed to update preferences');
+      }
+
+      return response.json();
+    },
+    onError: (error: Error) => {
+      notifyError(error.message || 'Failed to update preferences');
+    },
+  });
+};
+
+/**
+ * Mutation hook for exporting user data.
+ *
+ * @example
+ * ```tsx
+ * const exportData = useExportDataMutation();
+ * exportData.mutate();
+ * ```
+ */
+export const useExportDataMutation = () => {
+  return useMutation({
+    mutationFn: async (): Promise<unknown> => {
+      const response = await apiClient.exportUserData();
+
+      if (!response.ok) {
+        const error = await response.json().catch(() => ({
+          message: `Request failed with status ${response.status}`,
+        }));
+        throw new Error(error.message || 'Failed to export data');
+      }
+
+      return response.json();
+    },
+    onError: (error: Error) => {
+      notifyError(error.message || 'Failed to export data');
+    },
+  });
+};
+
+/**
+ * Mutation hook for deleting user account.
+ *
+ * @example
+ * ```tsx
+ * const deleteAccount = useDeleteAccountMutation();
+ * deleteAccount.mutate({ password: 'currentPassword' });
+ * ```
+ */
+export const useDeleteAccountMutation = () => {
+  return useMutation({
+    mutationFn: async ({ password }: { password: string }): Promise<void> => {
+      const response = await apiClient.deleteUserAccount(password);
+
+      if (!response.ok) {
+        const error = await response.json().catch(() => ({
+          message: `Request failed with status ${response.status}`,
+        }));
+        throw new Error(error.message || 'Failed to delete account');
+      }
+
+      return response.json();
+    },
+    onError: (error: Error) => {
+      notifyError(error.message || 'Failed to delete account');
+    },
+  });
+};
diff --git a/src/hooks/mutations/useRemoveShoppingListItemMutation.ts b/src/hooks/mutations/useRemoveShoppingListItemMutation.ts
index e653df93..9819927b 100644
--- a/src/hooks/mutations/useRemoveShoppingListItemMutation.ts
+++ b/src/hooks/mutations/useRemoveShoppingListItemMutation.ts
@@ -2,6 +2,7 @@
 import { useMutation, useQueryClient } from '@tanstack/react-query';
 import * as apiClient from '../../services/apiClient';
 import { notifySuccess, notifyError } from '../../services/notificationService';
+import { queryKeyBases } from '../../config/queryKeys';
 
 interface RemoveShoppingListItemParams {
   itemId: number;
@@ -48,7 +49,7 @@ export const useRemoveShoppingListItemMutation = () => {
     },
     onSuccess: () => {
       // Invalidate and refetch shopping lists to get the updated list
-      queryClient.invalidateQueries({ queryKey: ['shopping-lists'] });
+      queryClient.invalidateQueries({ queryKey: queryKeyBases.shoppingLists });
       notifySuccess('Item removed from shopping list');
     },
     onError: (error: Error) => {
diff --git a/src/hooks/mutations/useRemoveWatchedItemMutation.ts b/src/hooks/mutations/useRemoveWatchedItemMutation.ts
index cdf5ad93..0537d1ea 100644
--- a/src/hooks/mutations/useRemoveWatchedItemMutation.ts
+++ b/src/hooks/mutations/useRemoveWatchedItemMutation.ts
@@ -2,6 +2,7 @@
 import { useMutation, useQueryClient } from '@tanstack/react-query';
 import * as apiClient from '../../services/apiClient';
 import { notifySuccess, notifyError } from '../../services/notificationService';
+import { queryKeyBases } from '../../config/queryKeys';
 
 interface RemoveWatchedItemParams {
   masterItemId: number;
@@ -48,7 +49,7 @@ export const useRemoveWatchedItemMutation = () => {
     },
     onSuccess: () => {
       // Invalidate and refetch watched items to get the updated list
-      queryClient.invalidateQueries({ queryKey: ['watched-items'] });
+      queryClient.invalidateQueries({ queryKey: queryKeyBases.watchedItems });
       notifySuccess('Item removed from watched list');
     },
     onError: (error: Error) => {
diff --git a/src/hooks/mutations/useUpdateShoppingListItemMutation.ts b/src/hooks/mutations/useUpdateShoppingListItemMutation.ts
index d46e630f..bc1d73f3 100644
--- a/src/hooks/mutations/useUpdateShoppingListItemMutation.ts
+++ b/src/hooks/mutations/useUpdateShoppingListItemMutation.ts
@@ -2,6 +2,7 @@
 import { useMutation, useQueryClient } from '@tanstack/react-query';
 import * as apiClient from '../../services/apiClient';
 import { notifySuccess, notifyError } from '../../services/notificationService';
+import { queryKeyBases } from '../../config/queryKeys';
 import type { ShoppingListItem } from '../../types';
 
 interface UpdateShoppingListItemParams {
@@ -60,7 +61,7 @@ export const useUpdateShoppingListItemMutation = () => {
     },
     onSuccess: () => {
       // Invalidate and refetch shopping lists to get the updated list
-      queryClient.invalidateQueries({ queryKey: ['shopping-lists'] });
+      queryClient.invalidateQueries({ queryKey: queryKeyBases.shoppingLists });
       notifySuccess('Shopping list item updated');
     },
     onError: (error: Error) => {
diff --git a/src/hooks/queries/useActivityLogQuery.ts b/src/hooks/queries/useActivityLogQuery.ts
index 418791d1..e077bac7 100644
--- a/src/hooks/queries/useActivityLogQuery.ts
+++ b/src/hooks/queries/useActivityLogQuery.ts
@@ -1,6 +1,7 @@
 // src/hooks/queries/useActivityLogQuery.ts
 import { useQuery } from '@tanstack/react-query';
 import { fetchActivityLog } from '../../services/apiClient';
+import { queryKeys } from '../../config/queryKeys';
 import type { ActivityLogItem } from '../../types';
 
 /**
@@ -21,7 +22,7 @@ import type { ActivityLogItem } from '../../types';
  */
 export const useActivityLogQuery = (limit: number = 20, offset: number = 0) => {
   return useQuery({
-    queryKey: ['activity-log', { limit, offset }],
+    queryKey: queryKeys.activityLog(limit, offset),
     queryFn: async (): Promise<ActivityLogItem[]> => {
       const response = await fetchActivityLog(limit, offset);
 
diff --git a/src/hooks/queries/useApplicationStatsQuery.ts b/src/hooks/queries/useApplicationStatsQuery.ts
index b5160082..f5647007 100644
--- a/src/hooks/queries/useApplicationStatsQuery.ts
+++ b/src/hooks/queries/useApplicationStatsQuery.ts
@@ -1,6 +1,7 @@
 // src/hooks/queries/useApplicationStatsQuery.ts
 import { useQuery } from '@tanstack/react-query';
 import { getApplicationStats, AppStats } from '../../services/apiClient';
+import { queryKeys } from '../../config/queryKeys';
 
 /**
  * Query hook for fetching application-wide statistics (admin feature).
@@ -19,7 +20,7 @@ import { getApplicationStats, AppStats } from '../../services/apiClient';
  */
 export const useApplicationStatsQuery = () => {
   return useQuery({
-    queryKey: ['application-stats'],
+    queryKey: queryKeys.applicationStats(),
     queryFn: async (): Promise<AppStats> => {
       const response = await getApplicationStats();
 
diff --git a/src/hooks/queries/useAuthProfileQuery.ts b/src/hooks/queries/useAuthProfileQuery.ts
index 027a3e5c..09479229 100644
--- a/src/hooks/queries/useAuthProfileQuery.ts
+++ b/src/hooks/queries/useAuthProfileQuery.ts
@@ -2,13 +2,15 @@
 import { useQuery, useQueryClient } from '@tanstack/react-query';
 import { getAuthenticatedUserProfile } from '../../services/apiClient';
 import { getToken } from '../../services/tokenStorage';
+import { queryKeys, queryKeyBases } from '../../config/queryKeys';
 import type { UserProfile } from '../../types';
 
 /**
  * Query key for the authenticated user's profile.
  * Exported for cache invalidation purposes.
+ * @deprecated Use queryKeys.authProfile() from '../../config/queryKeys' instead
  */
-export const AUTH_PROFILE_QUERY_KEY = ['auth-profile'] as const;
+export const AUTH_PROFILE_QUERY_KEY = queryKeys.authProfile();
 
 /**
  * Query hook for fetching the authenticated user's profile.
@@ -28,7 +30,7 @@ export const useAuthProfileQuery = (enabled: boolean = true) => {
   const hasToken = !!getToken();
 
   return useQuery({
-    queryKey: AUTH_PROFILE_QUERY_KEY,
+    queryKey: queryKeys.authProfile(),
     queryFn: async (): Promise<UserProfile> => {
       const response = await getAuthenticatedUserProfile();
 
@@ -55,6 +57,6 @@ export const useInvalidateAuthProfile = () => {
   const queryClient = useQueryClient();
 
   return () => {
-    queryClient.invalidateQueries({ queryKey: AUTH_PROFILE_QUERY_KEY });
+    queryClient.invalidateQueries({ queryKey: queryKeyBases.authProfile });
   };
 };
diff --git a/src/hooks/queries/useBestSalePricesQuery.ts b/src/hooks/queries/useBestSalePricesQuery.ts
index 27b24434..275bdd68 100644
--- a/src/hooks/queries/useBestSalePricesQuery.ts
+++ b/src/hooks/queries/useBestSalePricesQuery.ts
@@ -1,6 +1,7 @@
 // src/hooks/queries/useBestSalePricesQuery.ts
 import { useQuery } from '@tanstack/react-query';
 import { fetchBestSalePrices } from '../../services/apiClient';
+import { queryKeys } from '../../config/queryKeys';
 import type { WatchedItemDeal } from '../../types';
 
 /**
@@ -19,7 +20,7 @@ import type { WatchedItemDeal } from '../../types';
  */
 export const useBestSalePricesQuery = (enabled: boolean = true) => {
   return useQuery({
-    queryKey: ['best-sale-prices'],
+    queryKey: queryKeys.bestSalePrices(),
     queryFn: async (): Promise<WatchedItemDeal[]> => {
       const response = await fetchBestSalePrices();
 
diff --git a/src/hooks/queries/useBrandsQuery.ts b/src/hooks/queries/useBrandsQuery.ts
new file mode 100644
index 00000000..b9078ee9
--- /dev/null
+++ b/src/hooks/queries/useBrandsQuery.ts
@@ -0,0 +1,35 @@
+// src/hooks/queries/useBrandsQuery.ts
+import { useQuery } from '@tanstack/react-query';
+import { fetchAllBrands } from '../../services/apiClient';
+import type { Brand } from '../../types';
+
+/**
+ * Query hook for fetching all brands (admin feature).
+ *
+ * @param enabled - Whether the query should run (default: true)
+ * @returns TanStack Query result with Brand[] data
+ *
+ * @example
+ * ```tsx
+ * const { data: brands = [], isLoading, error } = useBrandsQuery();
+ * ```
+ */
+export const useBrandsQuery = (enabled: boolean = true) => {
+  return useQuery({
+    queryKey: ['brands'],
+    queryFn: async (): Promise<Brand[]> => {
+      const response = await fetchAllBrands();
+
+      if (!response.ok) {
+        const error = await response.json().catch(() => ({
+          message: `Request failed with status ${response.status}`,
+        }));
+        throw new Error(error.message || 'Failed to fetch brands');
+      }
+
+      return response.json();
+    },
+    enabled,
+    staleTime: 1000 * 60 * 5, // 5 minutes - brands don't change frequently
+  });
+};
diff --git a/src/hooks/queries/useCategoriesQuery.ts b/src/hooks/queries/useCategoriesQuery.ts
index cc2cb0d3..62d2ed0b 100644
--- a/src/hooks/queries/useCategoriesQuery.ts
+++ b/src/hooks/queries/useCategoriesQuery.ts
@@ -1,6 +1,7 @@
 // src/hooks/queries/useCategoriesQuery.ts
 import { useQuery } from '@tanstack/react-query';
 import { fetchCategories } from '../../services/apiClient';
+import { queryKeys } from '../../config/queryKeys';
 import type { Category } from '../../types';
 
 /**
@@ -14,7 +15,7 @@ import type { Category } from '../../types';
  */
 export const useCategoriesQuery = () => {
   return useQuery({
-    queryKey: ['categories'],
+    queryKey: queryKeys.categories(),
     queryFn: async (): Promise<Category[]> => {
       const response = await fetchCategories();
 
diff --git a/src/hooks/queries/useFlyerItemCountQuery.ts b/src/hooks/queries/useFlyerItemCountQuery.ts
index acf8bc21..54a86913 100644
--- a/src/hooks/queries/useFlyerItemCountQuery.ts
+++ b/src/hooks/queries/useFlyerItemCountQuery.ts
@@ -1,6 +1,7 @@
 // src/hooks/queries/useFlyerItemCountQuery.ts
 import { useQuery } from '@tanstack/react-query';
 import { countFlyerItemsForFlyers } from '../../services/apiClient';
+import { queryKeys } from '../../config/queryKeys';
 
 interface FlyerItemCount {
   count: number;
@@ -24,7 +25,7 @@ interface FlyerItemCount {
 export const useFlyerItemCountQuery = (flyerIds: number[], enabled: boolean = true) => {
   return useQuery({
     // Include flyerIds in the key so cache is per-set of flyers
-    queryKey: ['flyer-items-count', flyerIds.sort().join(',')],
+    queryKey: queryKeys.flyerItemsCount(flyerIds),
     queryFn: async (): Promise<FlyerItemCount> => {
       if (flyerIds.length === 0) {
         return { count: 0 };
diff --git a/src/hooks/queries/useFlyerItemsForFlyersQuery.ts b/src/hooks/queries/useFlyerItemsForFlyersQuery.ts
index b884fae1..de757310 100644
--- a/src/hooks/queries/useFlyerItemsForFlyersQuery.ts
+++ b/src/hooks/queries/useFlyerItemsForFlyersQuery.ts
@@ -1,6 +1,7 @@
 // src/hooks/queries/useFlyerItemsForFlyersQuery.ts
 import { useQuery } from '@tanstack/react-query';
 import { fetchFlyerItemsForFlyers } from '../../services/apiClient';
+import { queryKeys } from '../../config/queryKeys';
 import type { FlyerItem } from '../../types';
 
 /**
@@ -21,7 +22,7 @@ import type { FlyerItem } from '../../types';
 export const useFlyerItemsForFlyersQuery = (flyerIds: number[], enabled: boolean = true) => {
   return useQuery({
     // Include flyerIds in the key so cache is per-set of flyers
-    queryKey: ['flyer-items-batch', flyerIds.sort().join(',')],
+    queryKey: queryKeys.flyerItemsBatch(flyerIds),
     queryFn: async (): Promise<FlyerItem[]> => {
       if (flyerIds.length === 0) {
         return [];
diff --git a/src/hooks/queries/useFlyerItemsQuery.ts b/src/hooks/queries/useFlyerItemsQuery.ts
index bf8b18a8..9dee1831 100644
--- a/src/hooks/queries/useFlyerItemsQuery.ts
+++ b/src/hooks/queries/useFlyerItemsQuery.ts
@@ -1,6 +1,7 @@
 // src/hooks/queries/useFlyerItemsQuery.ts
 import { useQuery } from '@tanstack/react-query';
 import * as apiClient from '../../services/apiClient';
+import { queryKeys } from '../../config/queryKeys';
 import type { FlyerItem } from '../../types';
 
 /**
@@ -19,7 +20,7 @@ import type { FlyerItem } from '../../types';
  */
 export const useFlyerItemsQuery = (flyerId: number | undefined) => {
   return useQuery({
-    queryKey: ['flyer-items', flyerId],
+    queryKey: queryKeys.flyerItems(flyerId as number),
     queryFn: async (): Promise<FlyerItem[]> => {
       if (!flyerId) {
         throw new Error('Flyer ID is required');
diff --git a/src/hooks/queries/useFlyersQuery.ts b/src/hooks/queries/useFlyersQuery.ts
index 5e4f58c7..9db3c035 100644
--- a/src/hooks/queries/useFlyersQuery.ts
+++ b/src/hooks/queries/useFlyersQuery.ts
@@ -1,6 +1,7 @@
 // src/hooks/queries/useFlyersQuery.ts
 import { useQuery } from '@tanstack/react-query';
 import * as apiClient from '../../services/apiClient';
+import { queryKeys } from '../../config/queryKeys';
 import type { Flyer } from '../../types';
 
 /**
@@ -20,7 +21,7 @@ import type { Flyer } from '../../types';
  */
 export const useFlyersQuery = (limit: number = 20, offset: number = 0) => {
   return useQuery({
-    queryKey: ['flyers', { limit, offset }],
+    queryKey: queryKeys.flyers(limit, offset),
     queryFn: async (): Promise<Flyer[]> => {
       const response = await apiClient.fetchFlyers(limit, offset);
 
diff --git a/src/hooks/queries/useLeaderboardQuery.ts b/src/hooks/queries/useLeaderboardQuery.ts
index 7a9602a0..5b43fa84 100644
--- a/src/hooks/queries/useLeaderboardQuery.ts
+++ b/src/hooks/queries/useLeaderboardQuery.ts
@@ -1,6 +1,7 @@
 // src/hooks/queries/useLeaderboardQuery.ts
 import { useQuery } from '@tanstack/react-query';
 import { fetchLeaderboard } from '../../services/apiClient';
+import { queryKeys } from '../../config/queryKeys';
 import type { LeaderboardUser } from '../../types';
 
 /**
@@ -17,7 +18,7 @@ import type { LeaderboardUser } from '../../types';
  */
 export const useLeaderboardQuery = (limit: number = 10, enabled: boolean = true) => {
   return useQuery({
-    queryKey: ['leaderboard', limit],
+    queryKey: queryKeys.leaderboard(limit),
     queryFn: async (): Promise<LeaderboardUser[]> => {
       const response = await fetchLeaderboard(limit);
 
diff --git a/src/hooks/queries/useMasterItemsQuery.ts b/src/hooks/queries/useMasterItemsQuery.ts
index 5d4c1c03..ac77974c 100644
--- a/src/hooks/queries/useMasterItemsQuery.ts
+++ b/src/hooks/queries/useMasterItemsQuery.ts
@@ -1,6 +1,7 @@
 // src/hooks/queries/useMasterItemsQuery.ts
 import { useQuery } from '@tanstack/react-query';
 import * as apiClient from '../../services/apiClient';
+import { queryKeys } from '../../config/queryKeys';
 import type { MasterGroceryItem } from '../../types';
 
 /**
@@ -19,7 +20,7 @@ import type { MasterGroceryItem } from '../../types';
  */
 export const useMasterItemsQuery = () => {
   return useQuery({
-    queryKey: ['master-items'],
+    queryKey: queryKeys.masterItems(),
     queryFn: async (): Promise<MasterGroceryItem[]> => {
       const response = await apiClient.fetchMasterItems();
 
diff --git a/src/hooks/queries/usePriceHistoryQuery.ts b/src/hooks/queries/usePriceHistoryQuery.ts
index 172b5d9a..6fb23811 100644
--- a/src/hooks/queries/usePriceHistoryQuery.ts
+++ b/src/hooks/queries/usePriceHistoryQuery.ts
@@ -1,6 +1,7 @@
 // src/hooks/queries/usePriceHistoryQuery.ts
 import { useQuery } from '@tanstack/react-query';
 import { fetchHistoricalPriceData } from '../../services/apiClient';
+import { queryKeys } from '../../config/queryKeys';
 import type { HistoricalPriceDataPoint } from '../../types';
 
 /**
@@ -17,11 +18,8 @@ import type { HistoricalPriceDataPoint } from '../../types';
  * ```
  */
 export const usePriceHistoryQuery = (masterItemIds: number[], enabled: boolean = true) => {
-  // Sort IDs for stable query key
-  const sortedIds = [...masterItemIds].sort((a, b) => a - b);
-
   return useQuery({
-    queryKey: ['price-history', sortedIds.join(',')],
+    queryKey: queryKeys.priceHistory(masterItemIds),
     queryFn: async (): Promise<HistoricalPriceDataPoint[]> => {
       if (masterItemIds.length === 0) {
         return [];
diff --git a/src/hooks/queries/useShoppingListsQuery.ts b/src/hooks/queries/useShoppingListsQuery.ts
index fcfb0af3..a780e92c 100644
--- a/src/hooks/queries/useShoppingListsQuery.ts
+++ b/src/hooks/queries/useShoppingListsQuery.ts
@@ -1,6 +1,7 @@
 // src/hooks/queries/useShoppingListsQuery.ts
 import { useQuery } from '@tanstack/react-query';
 import * as apiClient from '../../services/apiClient';
+import { queryKeys } from '../../config/queryKeys';
 import type { ShoppingList } from '../../types';
 
 /**
@@ -19,7 +20,7 @@ import type { ShoppingList } from '../../types';
  */
 export const useShoppingListsQuery = (enabled: boolean) => {
   return useQuery({
-    queryKey: ['shopping-lists'],
+    queryKey: queryKeys.shoppingLists(),
     queryFn: async (): Promise<ShoppingList[]> => {
       const response = await apiClient.fetchShoppingLists();
 
diff --git a/src/hooks/queries/useSuggestedCorrectionsQuery.ts b/src/hooks/queries/useSuggestedCorrectionsQuery.ts
index 1aa7534f..1de53b95 100644
--- a/src/hooks/queries/useSuggestedCorrectionsQuery.ts
+++ b/src/hooks/queries/useSuggestedCorrectionsQuery.ts
@@ -1,6 +1,7 @@
 // src/hooks/queries/useSuggestedCorrectionsQuery.ts
 import { useQuery } from '@tanstack/react-query';
 import { getSuggestedCorrections } from '../../services/apiClient';
+import { queryKeys } from '../../config/queryKeys';
 import type { SuggestedCorrection } from '../../types';
 
 /**
@@ -14,7 +15,7 @@ import type { SuggestedCorrection } from '../../types';
  */
 export const useSuggestedCorrectionsQuery = () => {
   return useQuery({
-    queryKey: ['suggested-corrections'],
+    queryKey: queryKeys.suggestedCorrections(),
     queryFn: async (): Promise<SuggestedCorrection[]> => {
       const response = await getSuggestedCorrections();
 
diff --git a/src/hooks/queries/useUserAddressQuery.ts b/src/hooks/queries/useUserAddressQuery.ts
index aedeab6b..d535fb8f 100644
--- a/src/hooks/queries/useUserAddressQuery.ts
+++ b/src/hooks/queries/useUserAddressQuery.ts
@@ -1,6 +1,7 @@
 // src/hooks/queries/useUserAddressQuery.ts
 import { useQuery } from '@tanstack/react-query';
 import { getUserAddress } from '../../services/apiClient';
+import { queryKeys } from '../../config/queryKeys';
 import type { Address } from '../../types';
 
 /**
@@ -20,7 +21,7 @@ export const useUserAddressQuery = (
   enabled: boolean = true,
 ) => {
   return useQuery({
-    queryKey: ['user-address', addressId],
+    queryKey: queryKeys.userAddress(addressId ?? null),
     queryFn: async (): Promise<Address> => {
       if (!addressId) {
         throw new Error('Address ID is required');
diff --git a/src/hooks/queries/useUserProfileDataQuery.ts b/src/hooks/queries/useUserProfileDataQuery.ts
index eadeaa02..8013e23b 100644
--- a/src/hooks/queries/useUserProfileDataQuery.ts
+++ b/src/hooks/queries/useUserProfileDataQuery.ts
@@ -1,6 +1,7 @@
 // src/hooks/queries/useUserProfileDataQuery.ts
 import { useQuery } from '@tanstack/react-query';
 import { getAuthenticatedUserProfile, getUserAchievements } from '../../services/apiClient';
+import { queryKeys } from '../../config/queryKeys';
 import type { UserProfile, Achievement, UserAchievement } from '../../types';
 
 interface UserProfileData {
@@ -26,7 +27,7 @@ interface UserProfileData {
  */
 export const useUserProfileDataQuery = (enabled: boolean = true) => {
   return useQuery({
-    queryKey: ['user-profile-data'],
+    queryKey: queryKeys.userProfileData(),
     queryFn: async (): Promise<UserProfileData> => {
       const [profileRes, achievementsRes] = await Promise.all([
         getAuthenticatedUserProfile(),
diff --git a/src/hooks/queries/useWatchedItemsQuery.ts b/src/hooks/queries/useWatchedItemsQuery.ts
index 5ca4b9ce..1ee4d471 100644
--- a/src/hooks/queries/useWatchedItemsQuery.ts
+++ b/src/hooks/queries/useWatchedItemsQuery.ts
@@ -1,6 +1,7 @@
 // src/hooks/queries/useWatchedItemsQuery.ts
 import { useQuery } from '@tanstack/react-query';
 import * as apiClient from '../../services/apiClient';
+import { queryKeys } from '../../config/queryKeys';
 import type { MasterGroceryItem } from '../../types';
 
 /**
@@ -19,7 +20,7 @@ import type { MasterGroceryItem } from '../../types';
  */
 export const useWatchedItemsQuery = (enabled: boolean) => {
   return useQuery({
-    queryKey: ['watched-items'],
+    queryKey: queryKeys.watchedItems(),
     queryFn: async (): Promise<MasterGroceryItem[]> => {
       const response = await apiClient.fetchWatchedItems();
 
diff --git a/src/pages/admin/components/AdminBrandManager.tsx b/src/pages/admin/components/AdminBrandManager.tsx
index 7f019e3f..466d07b5 100644
--- a/src/pages/admin/components/AdminBrandManager.tsx
+++ b/src/pages/admin/components/AdminBrandManager.tsx
@@ -1,36 +1,22 @@
 // src/pages/admin/components/AdminBrandManager.tsx
-import React, { useState, useCallback } from 'react';
+import React, { useState } from 'react';
 import toast from 'react-hot-toast';
-import { fetchAllBrands, uploadBrandLogo } from '../../../services/apiClient';
+import { uploadBrandLogo } from '../../../services/apiClient';
 import { Brand } from '../../../types';
 import { ErrorDisplay } from '../../../components/ErrorDisplay';
-import { useApiOnMount } from '../../../hooks/useApiOnMount';
+import { useBrandsQuery } from '../../../hooks/queries/useBrandsQuery';
 import { logger } from '../../../services/logger.client';
 
 export const AdminBrandManager: React.FC = () => {
-  // Wrap the fetcher function in useCallback to prevent it from being recreated on every render.
-  // The hook expects a function that returns a Promise<Response>, and it will handle
-  // the JSON parsing and error checking internally.
-  const fetchBrandsWrapper = useCallback(() => {
-    logger.debug(
-      '[AdminBrandManager] The memoized fetchBrandsWrapper is being passed to useApiOnMount',
-    );
-    // This wrapper simply calls the API client function. The hook will manage the promise.
-    return fetchAllBrands();
-  }, []); // An empty dependency array ensures this function is created only once.
+  const { data: initialBrands, isLoading: loading, error } = useBrandsQuery();
 
-  const {
-    data: initialBrands,
-    loading,
-    error,
-  } = useApiOnMount<Brand[], []>(fetchBrandsWrapper, []);
   // This state will hold a modified list of brands only after an optimistic update (e.g., logo upload).
   // It starts as null, indicating that we should use the original data from the API.
   const [updatedBrands, setUpdatedBrands] = useState<Brand[] | null>(null);
 
   // At render time, decide which data to display. If updatedBrands exists, it takes precedence.
   // Otherwise, fall back to the initial data from the hook. Default to an empty array.
-  const brandsToRender = updatedBrands || initialBrands || [];
+  const brandsToRender: Brand[] = updatedBrands || initialBrands || [];
   logger.debug(
     {
       loading,
diff --git a/src/pages/admin/components/AuthView.tsx b/src/pages/admin/components/AuthView.tsx
index 0c918851..a6325677 100644
--- a/src/pages/admin/components/AuthView.tsx
+++ b/src/pages/admin/components/AuthView.tsx
@@ -1,18 +1,16 @@
 // src/pages/admin/components/AuthView.tsx
 import React, { useState } from 'react';
 import type { UserProfile } from '../../../types';
-import { useApi } from '../../../hooks/useApi';
-import * as apiClient from '../../../services/apiClient';
 import { notifySuccess } from '../../../services/notificationService';
 import { LoadingSpinner } from '../../../components/LoadingSpinner';
 import { GoogleIcon } from '../../../components/icons/GoogleIcon';
 import { GithubIcon } from '../../../components/icons/GithubIcon';
 import { PasswordInput } from '../../../components/PasswordInput';
-
-interface AuthResponse {
-  userprofile: UserProfile;
-  token: string;
-}
+import {
+  useLoginMutation,
+  useRegisterMutation,
+  usePasswordResetRequestMutation,
+} from '../../../hooks/mutations/useAuthMutations';
 
 interface AuthViewProps {
   onLoginSuccess: (user: UserProfile, token: string, rememberMe: boolean) => void;
@@ -27,37 +25,50 @@ export const AuthView: React.FC<AuthViewProps> = ({ onLoginSuccess, onClose }) =
   const [isForgotPassword, setIsForgotPassword] = useState(false);
   const [rememberMe, setRememberMe] = useState(false);
 
-  const { execute: executeLogin, loading: loginLoading } = useApi<
-    AuthResponse,
-    [string, string, boolean]
-  >(apiClient.loginUser);
-  const { execute: executeRegister, loading: registerLoading } = useApi<
-    AuthResponse,
-    [string, string, string, string]
-  >(apiClient.registerUser);
-  const { execute: executePasswordReset, loading: passwordResetLoading } = useApi<
-    { message: string },
-    [string]
-  >(apiClient.requestPasswordReset);
+  const loginMutation = useLoginMutation();
+  const registerMutation = useRegisterMutation();
+  const passwordResetMutation = usePasswordResetRequestMutation();
+
+  const loginLoading = loginMutation.isPending;
+  const registerLoading = registerMutation.isPending;
+  const passwordResetLoading = passwordResetMutation.isPending;
 
   const handleAuthSubmit = async (e: React.FormEvent) => {
     e.preventDefault();
-    const authResult = isRegistering
-      ? await executeRegister(authEmail, authPassword, authFullName, '')
-      : await executeLogin(authEmail, authPassword, rememberMe);
 
-    if (authResult) {
-      onLoginSuccess(authResult.userprofile, authResult.token, rememberMe);
-      onClose();
+    if (isRegistering) {
+      registerMutation.mutate(
+        { email: authEmail, password: authPassword, fullName: authFullName },
+        {
+          onSuccess: (authResult) => {
+            onLoginSuccess(authResult.userprofile, authResult.token, rememberMe);
+            onClose();
+          },
+        },
+      );
+    } else {
+      loginMutation.mutate(
+        { email: authEmail, password: authPassword, rememberMe },
+        {
+          onSuccess: (authResult) => {
+            onLoginSuccess(authResult.userprofile, authResult.token, rememberMe);
+            onClose();
+          },
+        },
+      );
     }
   };
 
   const handlePasswordResetRequest = async (e: React.FormEvent) => {
     e.preventDefault();
-    const result = await executePasswordReset(authEmail);
-    if (result) {
-      notifySuccess(result.message);
-    }
+    passwordResetMutation.mutate(
+      { email: authEmail },
+      {
+        onSuccess: (result) => {
+          notifySuccess(result.message);
+        },
+      },
+    );
   };
 
   const handleOAuthSignIn = (provider: 'google' | 'github') => {
diff --git a/src/pages/admin/components/ProfileManager.tsx b/src/pages/admin/components/ProfileManager.tsx
index 5419ab48..53e28eee 100644
--- a/src/pages/admin/components/ProfileManager.tsx
+++ b/src/pages/admin/components/ProfileManager.tsx
@@ -1,21 +1,27 @@
 // src/pages/admin/components/ProfileManager.tsx
 import React, { useState, useEffect } from 'react';
 import type { Profile, Address, UserProfile } from '../../../types';
-import { useApi } from '../../../hooks/useApi';
-import * as apiClient from '../../../services/apiClient';
 import { notifySuccess, notifyError } from '../../../services/notificationService';
 import { logger } from '../../../services/logger.client';
 import { LoadingSpinner } from '../../../components/LoadingSpinner';
 import { XMarkIcon } from '../../../components/icons/XMarkIcon';
 import { GoogleIcon } from '../../../components/icons/GoogleIcon';
 import { GithubIcon } from '../../../components/icons/GithubIcon';
-import { ConfirmationModal } from '../../../components/ConfirmationModal'; // This path is correct
+import { ConfirmationModal } from '../../../components/ConfirmationModal';
 import { PasswordInput } from '../../../components/PasswordInput';
 import { MapView } from '../../../components/MapView';
 import type { AuthStatus } from '../../../hooks/useAuth';
 import { AuthView } from './AuthView';
 import { AddressForm } from './AddressForm';
 import { useProfileAddress } from '../../../hooks/useProfileAddress';
+import {
+  useUpdateProfileMutation,
+  useUpdateAddressMutation,
+  useUpdatePasswordMutation,
+  useUpdatePreferencesMutation,
+  useExportDataMutation,
+  useDeleteAccountMutation,
+} from '../../../hooks/mutations/useProfileMutations';
 
 export interface ProfileManagerProps {
   isOpen: boolean;
@@ -27,23 +33,6 @@ export interface ProfileManagerProps {
   onLoginSuccess: (user: UserProfile, token: string, rememberMe: boolean) => void; // Add login handler
 }
 
-// --- API Hook Wrappers ---
-// These wrappers adapt the apiClient functions (which expect an ApiOptions object)
-// to the signature expected by the useApi hook (which passes a raw AbortSignal).
-// They are defined outside the component to ensure they have a stable identity
-// across re-renders, preventing infinite loops in useEffect hooks.
-const updateAddressWrapper = (data: Partial<Address>, signal?: AbortSignal) =>
-  apiClient.updateUserAddress(data, { signal });
-const updatePasswordWrapper = (password: string, signal?: AbortSignal) =>
-  apiClient.updateUserPassword(password, { signal });
-const exportDataWrapper = (signal?: AbortSignal) => apiClient.exportUserData({ signal });
-const deleteAccountWrapper = (password: string, signal?: AbortSignal) =>
-  apiClient.deleteUserAccount(password, { signal });
-const updatePreferencesWrapper = (prefs: Partial<Profile['preferences']>, signal?: AbortSignal) =>
-  apiClient.updateUserPreferences(prefs, { signal });
-const updateProfileWrapper = (data: Partial<Profile>, signal?: AbortSignal) =>
-  apiClient.updateUserProfile(data, { signal });
-
 export const ProfileManager: React.FC<ProfileManagerProps> = ({
   isOpen,
   onClose,
@@ -63,32 +52,25 @@ export const ProfileManager: React.FC<ProfileManagerProps> = ({
   const { address, initialAddress, isGeocoding, handleAddressChange, handleManualGeocode } =
     useProfileAddress(userProfile, isOpen);
 
-  const { execute: updateProfile, loading: profileLoading } = useApi<Profile, [Partial<Profile>]>(
-    updateProfileWrapper,
-  );
-  const { execute: updateAddress, loading: addressLoading } = useApi<Address, [Partial<Address>]>(
-    updateAddressWrapper,
-  );
+  // TanStack Query mutations
+  const updateProfileMutation = useUpdateProfileMutation();
+  const updateAddressMutation = useUpdateAddressMutation();
+  const updatePasswordMutation = useUpdatePasswordMutation();
+  const updatePreferencesMutation = useUpdatePreferencesMutation();
+  const exportDataMutation = useExportDataMutation();
+  const deleteAccountMutation = useDeleteAccountMutation();
+
+  const profileLoading = updateProfileMutation.isPending;
+  const addressLoading = updateAddressMutation.isPending;
+  const passwordLoading = updatePasswordMutation.isPending;
+  const exportLoading = exportDataMutation.isPending;
+  const deleteLoading = deleteAccountMutation.isPending;
 
   // Password state
   const [password, setPassword] = useState('');
   const [confirmPassword, setConfirmPassword] = useState('');
-  const { execute: updatePassword, loading: passwordLoading } = useApi<unknown, [string]>(
-    updatePasswordWrapper,
-  );
   const [isDeleteModalOpen, setIsDeleteModalOpen] = useState(false);
 
-  // Data & Privacy state
-  const { execute: exportData, loading: exportLoading } = useApi<unknown, []>(exportDataWrapper);
-  const { execute: deleteAccount, loading: deleteLoading } = useApi<unknown, [string]>(
-    deleteAccountWrapper,
-  );
-
-  // Preferences state
-  const { execute: updatePreferences } = useApi<Profile, [Partial<Profile['preferences']>]>(
-    updatePreferencesWrapper,
-  );
-
   const [isConfirmingDelete, setIsConfirmingDelete] = useState(false);
   const [passwordForDelete, setPasswordForDelete] = useState('');
 
@@ -146,15 +128,16 @@ export const ProfileManager: React.FC<ProfileManagerProps> = ({
     }
 
     // Create an array of promises for the API calls that need to be made.
-    // Because useApi() catches errors and returns null, we can safely use Promise.all.
-    const promisesToRun = [];
+    const promisesToRun: Promise<Profile | Address>[] = [];
     if (profileDataChanged) {
       logger.debug('[handleProfileSave] Queuing profile update promise.');
-      promisesToRun.push(updateProfile({ full_name: fullName, avatar_url: avatarUrl }));
+      promisesToRun.push(
+        updateProfileMutation.mutateAsync({ full_name: fullName, avatar_url: avatarUrl }),
+      );
     }
     if (addressDataChanged) {
       logger.debug('[handleProfileSave] Queuing address update promise.');
-      promisesToRun.push(updateAddress(address));
+      promisesToRun.push(updateAddressMutation.mutateAsync(address));
     }
 
     try {
@@ -169,7 +152,7 @@ export const ProfileManager: React.FC<ProfileManagerProps> = ({
       // Determine which promises succeeded or failed.
       results.forEach((result, index) => {
         const isProfilePromise = profileDataChanged && index === 0;
-        if (result.status === 'rejected' || (result.status === 'fulfilled' && !result.value)) {
+        if (result.status === 'rejected') {
           anyFailures = true;
         } else if (result.status === 'fulfilled' && isProfilePromise) {
           successfulProfileUpdate = result.value as Profile;
@@ -187,12 +170,11 @@ export const ProfileManager: React.FC<ProfileManagerProps> = ({
         onClose();
       } else {
         logger.warn(
-          '[handleProfileSave] One or more operations failed. The useApi hook should have shown an error. The modal will remain open.',
+          '[handleProfileSave] One or more operations failed. The mutation hook should have shown an error. The modal will remain open.',
         );
       }
     } catch (error) {
-      // This catch block is a safeguard. In normal operation, the useApi hook
-      // should prevent any promises from rejecting.
+      // This catch block is a safeguard for unexpected errors.
       logger.error(
         { err: error },
         "[CRITICAL] An unexpected error was caught directly in handleProfileSave's catch block.",
@@ -229,51 +211,66 @@ export const ProfileManager: React.FC<ProfileManagerProps> = ({
       return;
     }
 
-    const result = await updatePassword(password);
-    if (result) {
-      notifySuccess('Password updated successfully!');
-      setPassword('');
-      setConfirmPassword('');
-    }
+    updatePasswordMutation.mutate(
+      { password },
+      {
+        onSuccess: () => {
+          notifySuccess('Password updated successfully!');
+          setPassword('');
+          setConfirmPassword('');
+        },
+      },
+    );
   };
 
   const handleExportData = async () => {
-    const userData = await exportData();
-    if (userData) {
-      const jsonString = `data:text/json;charset=utf-8,${encodeURIComponent(JSON.stringify(userData, null, 2))}`;
-      const link = document.createElement('a');
-      link.href = jsonString;
-      link.download = `flyer-crawler-data-export-${new Date().toISOString().split('T')[0]}.json`;
-      link.click();
-    }
+    exportDataMutation.mutate(undefined, {
+      onSuccess: (userData) => {
+        const jsonString = `data:text/json;charset=utf-8,${encodeURIComponent(JSON.stringify(userData, null, 2))}`;
+        const link = document.createElement('a');
+        link.href = jsonString;
+        link.download = `flyer-crawler-data-export-${new Date().toISOString().split('T')[0]}.json`;
+        link.click();
+      },
+    });
   };
 
   const handleDeleteAccount = async () => {
     setIsDeleteModalOpen(false); // Close the confirmation modal
-    const result = await deleteAccount(passwordForDelete);
-
-    if (result) {
-      // useApi returns null on failure, so this check is sufficient.
-      notifySuccess('Account deleted successfully. You will be logged out shortly.');
-      setTimeout(() => {
-        onClose();
-        onSignOut();
-      }, 3000);
-    }
+    deleteAccountMutation.mutate(
+      { password: passwordForDelete },
+      {
+        onSuccess: () => {
+          notifySuccess('Account deleted successfully. You will be logged out shortly.');
+          setTimeout(() => {
+            onClose();
+            onSignOut();
+          }, 3000);
+        },
+      },
+    );
   };
 
   const handleToggleDarkMode = async (newMode: boolean) => {
-    const updatedProfile = await updatePreferences({ darkMode: newMode });
-    if (updatedProfile) {
-      onProfileUpdate(updatedProfile);
-    }
+    updatePreferencesMutation.mutate(
+      { darkMode: newMode },
+      {
+        onSuccess: (updatedProfile) => {
+          onProfileUpdate(updatedProfile);
+        },
+      },
+    );
   };
 
   const handleToggleUnitSystem = async (newSystem: 'metric' | 'imperial') => {
-    const updatedProfile = await updatePreferences({ unitSystem: newSystem });
-    if (updatedProfile) {
-      onProfileUpdate(updatedProfile);
-    }
+    updatePreferencesMutation.mutate(
+      { unitSystem: newSystem },
+      {
+        onSuccess: (updatedProfile) => {
+          onProfileUpdate(updatedProfile);
+        },
+      },
+    );
   };
 
   if (!isOpen) return null;