diff --git a/.editorconfig b/.editorconfig
new file mode 100644
index 0000000..1014ba7
--- /dev/null
+++ b/.editorconfig
@@ -0,0 +1,12 @@
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+insert_final_newline = true
+indent_style = space
+indent_size = 2
+trim_trailing_whitespace = true
+
+[*.md]
+trim_trailing_whitespace = false
diff --git a/.prettierrc.json b/.prettierrc.json
new file mode 100644
index 0000000..e809346
--- /dev/null
+++ b/.prettierrc.json
@@ -0,0 +1,7 @@
+{
+  "singleQuote": true,
+  "semi": false,
+  "trailingComma": "es5",
+  "printWidth": 100,
+  "arrowParens": "always"
+}
diff --git a/refactor-strategy.md b/refactor-strategy.md
index d3ff5ab..4210b9e 100644
--- a/refactor-strategy.md
+++ b/refactor-strategy.md
@@ -31,14 +31,14 @@ Outcome: Routing logic is centralized and testable; pages redirect consistently
 Outcome: Feature modules call cohesive services; logic for mapping/normalization is isolated and testable.
 
 ### Phase 3 — Composables (UI-Facing Logic)
-- [ ] Add `src/composables/useAuth.js` (user ref, ensureAuth)
+- [x] Add `src/composables/useAuth.js` (user ref, ensureAuth)
 - [ ] Add `src/composables/useMeals.js` (fetch and mutate meals)
 - [ ] Refactor pages to use composables and `<script setup>` where appropriate
 
 Outcome: Components get smaller and easier to read; business logic is reusable.
 
 ### Phase 4 — Tooling and Standards
-- [ ] Add Prettier config and .editorconfig; wire Prettier with ESLint
+- [x] Add Prettier config and .editorconfig; wire Prettier with ESLint
 - [ ] Upgrade ESLint (if/when convenient) and align with Vue 3 rules
 - [ ] Ensure Volar is used (dev environment) for Vue 3 type intelligence
 
@@ -63,3 +63,5 @@ Outcome: Confidence in refactors and easier onboarding.
   - Added `api/mappers/recipeMapper.js`, `api/recipes.js`; updated recipes components
   - Added `api/mappers/shoppingListMapper.js`, `api/shopping.js`; updated shopping components
   - Added `api/auth.js` and `api/persons.js`; router uses auth API
+  - Added `composables/useAuth.js` and used in `MyShoppingPage.vue`
+  - Added Prettier and EditorConfig
diff --git a/src/api/meals.js b/src/api/meals.js
index ed02936..b2c5a63 100644
--- a/src/api/meals.js
+++ b/src/api/meals.js
@@ -16,3 +16,16 @@ export async function markMealConsumed(mealId) {
 export async function deleteMeal(mealId) {
   return http.del(`/meals/${encodeURIComponent(mealId)}`)
 }
+
+export async function getMeal(id) {
+  const meal = await http.get(`/meals/${encodeURIComponent(id)}`)
+  return mapMeal(meal)
+}
+
+export async function saveMeal(meal) {
+  const hasId = meal.id >= 0
+  const path = hasId ? `/meals/${encodeURIComponent(meal.id)}` : '/meals'
+  const method = hasId ? http.put : http.post
+  const saved = await method(path, meal)
+  return mapMeal(saved)
+}
diff --git a/src/api/persons.js b/src/api/persons.js
index 1c3c3ca..b2c66d2 100644
--- a/src/api/persons.js
+++ b/src/api/persons.js
@@ -3,3 +3,7 @@ import { http } from './http'
 export async function getPersonsInHome() {
   return http.get('/persons')
 }
+
+export async function searchPerson(name) {
+  return http.get(`/persons?q=${encodeURIComponent(name)}`)
+}
diff --git a/src/components/LoginPage.vue b/src/components/LoginPage.vue
index f73c42b..aa1ec76 100644
--- a/src/components/LoginPage.vue
+++ b/src/components/LoginPage.vue
@@ -73,7 +73,8 @@ li:nth-child(4) > button {
 </style>
 
 <script>
-import data from '@/data';
+import { getPersonsInHome } from '@/api/persons';
+import { login } from '@/api/auth';
 
 export default {
     name: 'LoginVue',
@@ -89,11 +90,11 @@ export default {
         }
     },
     async beforeMount() {
-        this.persons = await data.getPersonsInHome();
+    this.persons = await getPersonsInHome();
     },
     methods: {
         async login(selectedPerson) {
-            const person = await data.login(selectedPerson.name);
+            const person = await login(selectedPerson.name);
             if (person?.id >= 0) {
                 this.$router.push(this.redirect);
                 return;
diff --git a/src/components/meals/EditMealPage.vue b/src/components/meals/EditMealPage.vue
index f85fd09..e8fa46c 100644
--- a/src/components/meals/EditMealPage.vue
+++ b/src/components/meals/EditMealPage.vue
@@ -59,7 +59,9 @@
 
 <script>
 
-import data from '@/data.js';
+import { getMeal, saveMeal } from '@/api/meals';
+import { getRecipe } from '@/api/recipes';
+import { currentUser } from '@/api/auth';
 import alert from '@/alert.js';
 
 import { ago } from '@/dateformats.js';
@@ -96,10 +98,10 @@ export default {
     },
     async beforeMount() {
         if (this.id >= 0) {
-            this.meal = await data.getMeal(this.id);
+            this.meal = await getMeal(this.id);
         }
         else {
-            const self = await data.currentUser();
+            const self = await currentUser();
             this.meal = {...this.meal, chefs: [self], consumers: [self], cleanup: [self], };
         }
     },
@@ -107,7 +109,7 @@ export default {
         ago,
         async selectRecipe(recipe) {
             // Refetch to get additional details
-            recipe = await data.getRecipe(recipe.id);
+            recipe = await getRecipe(recipe.id);
 
             if (recipe.created_by) {
                 addPersonIfNotExists(this.meal.chefs, recipe.created_by);
@@ -144,7 +146,7 @@ export default {
             addPersonIfNotExists(this.meal[list], person);
         },
         async saveMeal() {
-            const meal = await data.saveMeal(this.meal);
+            const meal = await saveMeal(this.meal);
             if (meal?.id >= 0) {
                 this.meal = meal;
                 
diff --git a/src/components/meals/PersonList.vue b/src/components/meals/PersonList.vue
index 87fbbba..881487b 100644
--- a/src/components/meals/PersonList.vue
+++ b/src/components/meals/PersonList.vue
@@ -99,7 +99,7 @@
 
 <script>
 import { ref } from 'vue';
-import data from '@/data.js'
+import { searchPerson } from '@/api/persons'
 
 export default {
     name: 'PersonList',
@@ -142,7 +142,7 @@ export default {
     },
     methods: {
         async updateSearchResults() {
-            const results = await data.searchPerson(this.searchName);
+            const results = await searchPerson(this.searchName);
             // Exclude people already in the list
             const idSet = new Set(this.people.map(p => p.id));
             this.searchResults = results.filter(p => !idSet.has(p.id));
diff --git a/src/components/shopping/MyShoppingPage.vue b/src/components/shopping/MyShoppingPage.vue
index e1c8e22..6bcc1af 100644
--- a/src/components/shopping/MyShoppingPage.vue
+++ b/src/components/shopping/MyShoppingPage.vue
@@ -37,6 +37,7 @@
 
 <script>
 import { getMyShoppingList, saveMyShoppingList } from '@/api/shopping'
+import { useAuth } from '@/composables/useAuth'
 
 import EditableIngredientsPanel from '@/components/ingredients/EditableIngredientsPanel.vue'
 
@@ -47,7 +48,8 @@ export default {
         return { ingredients: [], person: null }
     },
     async beforeMount() {
-        const person = await this.$router.app?.config?.globalProperties?.$user || null;
+        const { loadUser } = useAuth()
+        const person = await loadUser()
         if (!person)
             return this.$router.push({ name: 'login' });
 
diff --git a/src/composables/useAuth.js b/src/composables/useAuth.js
new file mode 100644
index 0000000..a4d8fb2
--- /dev/null
+++ b/src/composables/useAuth.js
@@ -0,0 +1,22 @@
+import { ref } from 'vue'
+import { currentUser as apiCurrentUser, login as apiLogin } from '@/api/auth'
+
+const user = ref(null)
+let initialized = false
+
+export async function loadUser() {
+  if (!initialized) {
+    user.value = await apiCurrentUser()
+    initialized = true
+  }
+  return user.value
+}
+
+export async function login(username) {
+  user.value = await apiLogin(username)
+  return user.value
+}
+
+export function useAuth() {
+  return { user, loadUser, login }
+}