diff --git a/src/Resources/package-lock.json b/src/Resources/package-lock.json
index 0c6e71068..0926990af 100644
--- a/src/Resources/package-lock.json
+++ b/src/Resources/package-lock.json
@@ -51,6 +51,7 @@
         "prettier": "^3.2.5",
         "prettier-plugin-tailwindcss": "^0.6.5",
         "tailwindcss": "^3.4.6",
+        "ts-node": "^10.9.2",
         "typescript": "^5.4.0",
         "vite": "^5.3.1",
         "vite-plugin-vue-devtools": "^7.3.1",
@@ -668,6 +669,30 @@
         "node": ">=6.9.0"
       }
     },
+    "node_modules/@cspotcode/source-map-support": {
+      "version": "0.8.1",
+      "resolved": "https://registry.npmjs.org/@cspotcode/source-map-support/-/source-map-support-0.8.1.tgz",
+      "integrity": "sha512-IchNf6dN4tHoMFIn/7OE8LWZ19Y6q/67Bmf6vnGREv8RSbBVb9LPJxEcnwrcwX6ixSvaiGoomAUvu4YSxXrVgw==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@jridgewell/trace-mapping": "0.3.9"
+      },
+      "engines": {
+        "node": ">=12"
+      }
+    },
+    "node_modules/@cspotcode/source-map-support/node_modules/@jridgewell/trace-mapping": {
+      "version": "0.3.9",
+      "resolved": "https://registry.npmjs.org/@jridgewell/trace-mapping/-/trace-mapping-0.3.9.tgz",
+      "integrity": "sha512-3Belt6tdc8bPgAtbcmdtNJlirVoTmEb5e2gC94PnkwEW9jI6CAHUeoG85tjWP5WquqfavoMtMwiG4P926ZKKuQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@jridgewell/resolve-uri": "^3.0.3",
+        "@jridgewell/sourcemap-codec": "^1.4.10"
+      }
+    },
     "node_modules/@esbuild/linux-x64": {
       "version": "0.21.5",
       "cpu": [
@@ -1166,6 +1191,34 @@
         "node": ">=10.13.0"
       }
     },
+    "node_modules/@tsconfig/node10": {
+      "version": "1.0.11",
+      "resolved": "https://registry.npmjs.org/@tsconfig/node10/-/node10-1.0.11.tgz",
+      "integrity": "sha512-DcRjDCujK/kCk/cUe8Xz8ZSpm8mS3mNNpta+jGCA6USEDfktlNvm1+IuZ9eTcDbNk41BHwpHHeW+N1lKCz4zOw==",
+      "dev": true,
+      "license": "MIT"
+    },
+    "node_modules/@tsconfig/node12": {
+      "version": "1.0.11",
+      "resolved": "https://registry.npmjs.org/@tsconfig/node12/-/node12-1.0.11.tgz",
+      "integrity": "sha512-cqefuRsh12pWyGsIoBKJA9luFu3mRxCA+ORZvA4ktLSzIuCUtWVxGIuXigEwO5/ywWFMZ2QEGKWvkZG1zDMTag==",
+      "dev": true,
+      "license": "MIT"
+    },
+    "node_modules/@tsconfig/node14": {
+      "version": "1.0.3",
+      "resolved": "https://registry.npmjs.org/@tsconfig/node14/-/node14-1.0.3.tgz",
+      "integrity": "sha512-ysT8mhdixWK6Hw3i1V2AeRqZ5WfXg1G43mqoYlM2nc6388Fq5jcXyr5mRsqViLx/GJYdoL0bfXD8nmF+Zn/Iow==",
+      "dev": true,
+      "license": "MIT"
+    },
+    "node_modules/@tsconfig/node16": {
+      "version": "1.0.4",
+      "resolved": "https://registry.npmjs.org/@tsconfig/node16/-/node16-1.0.4.tgz",
+      "integrity": "sha512-vxhUy4J8lyeyinH7Azl1pdd43GJhZH/tP2weN8TntQblOY+A0XbT8DJk1/oCPuOOyg/Ja757rG0CgHcWC8OfMA==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/@tsconfig/node20": {
       "version": "20.1.4",
       "dev": true,
@@ -2461,6 +2514,13 @@
         "url": "https://opencollective.com/core-js"
       }
     },
+    "node_modules/create-require": {
+      "version": "1.1.1",
+      "resolved": "https://registry.npmjs.org/create-require/-/create-require-1.1.1.tgz",
+      "integrity": "sha512-dcKFX3jn0MpIaXjisoRvexIJVEKzaq7z2rZKxf+MSr9TkdmHmsU4m2lcLojrj/FHl8mk5VxMmYA+ftRkP/3oKQ==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/cross-spawn": {
       "version": "7.0.3",
       "dev": true,
@@ -2845,6 +2905,16 @@
       "dev": true,
       "license": "Apache-2.0"
     },
+    "node_modules/diff": {
+      "version": "4.0.2",
+      "resolved": "https://registry.npmjs.org/diff/-/diff-4.0.2.tgz",
+      "integrity": "sha512-58lmxKSA4BNyLz+HHMUzlOEpg09FV+ev6ZMe3vJihgdxzgcwZ8VoEEPmALCZG9LmqfVoNMMKpttIYTVG6uDY7A==",
+      "dev": true,
+      "license": "BSD-3-Clause",
+      "engines": {
+        "node": ">=0.3.1"
+      }
+    },
     "node_modules/diff-sequences": {
       "version": "29.6.3",
       "dev": true,
@@ -4669,6 +4739,13 @@
         "@jridgewell/sourcemap-codec": "^1.4.15"
       }
     },
+    "node_modules/make-error": {
+      "version": "1.3.6",
+      "resolved": "https://registry.npmjs.org/make-error/-/make-error-1.3.6.tgz",
+      "integrity": "sha512-s8UhlNe7vPKomQhC1qFelMokr/Sc3AgNbso3n74mVPA5LTZwkB9NlXf4XPamLxJE8h0gh73rM94xvwRT2CVInw==",
+      "dev": true,
+      "license": "ISC"
+    },
     "node_modules/mdn-data": {
       "version": "2.0.30",
       "resolved": "https://registry.npmjs.org/mdn-data/-/mdn-data-2.0.30.tgz",
@@ -7041,6 +7118,57 @@
       "dev": true,
       "license": "Apache-2.0"
     },
+    "node_modules/ts-node": {
+      "version": "10.9.2",
+      "resolved": "https://registry.npmjs.org/ts-node/-/ts-node-10.9.2.tgz",
+      "integrity": "sha512-f0FFpIdcHgn8zcPSbf1dRevwt047YMnaiJM3u2w2RewrB+fob/zePZcrOyQoLMMO7aBIddLcQIEK5dYjkLnGrQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@cspotcode/source-map-support": "^0.8.0",
+        "@tsconfig/node10": "^1.0.7",
+        "@tsconfig/node12": "^1.0.7",
+        "@tsconfig/node14": "^1.0.0",
+        "@tsconfig/node16": "^1.0.2",
+        "acorn": "^8.4.1",
+        "acorn-walk": "^8.1.1",
+        "arg": "^4.1.0",
+        "create-require": "^1.1.0",
+        "diff": "^4.0.1",
+        "make-error": "^1.1.1",
+        "v8-compile-cache-lib": "^3.0.1",
+        "yn": "3.1.1"
+      },
+      "bin": {
+        "ts-node": "dist/bin.js",
+        "ts-node-cwd": "dist/bin-cwd.js",
+        "ts-node-esm": "dist/bin-esm.js",
+        "ts-node-script": "dist/bin-script.js",
+        "ts-node-transpile-only": "dist/bin-transpile.js",
+        "ts-script": "dist/bin-script-deprecated.js"
+      },
+      "peerDependencies": {
+        "@swc/core": ">=1.2.50",
+        "@swc/wasm": ">=1.2.50",
+        "@types/node": "*",
+        "typescript": ">=2.7"
+      },
+      "peerDependenciesMeta": {
+        "@swc/core": {
+          "optional": true
+        },
+        "@swc/wasm": {
+          "optional": true
+        }
+      }
+    },
+    "node_modules/ts-node/node_modules/arg": {
+      "version": "4.1.3",
+      "resolved": "https://registry.npmjs.org/arg/-/arg-4.1.3.tgz",
+      "integrity": "sha512-58S9QDqG0Xx27YwPSt9fJxivjYl432YCwfDMfZ+71RAqUrZef7LrKQZ3LHLOwCS4FLNBplP533Zx895SeOCHvA==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/tslib": {
       "version": "2.6.3",
       "dev": true,
@@ -7179,6 +7307,13 @@
         "base64-arraybuffer": "^1.0.2"
       }
     },
+    "node_modules/v8-compile-cache-lib": {
+      "version": "3.0.1",
+      "resolved": "https://registry.npmjs.org/v8-compile-cache-lib/-/v8-compile-cache-lib-3.0.1.tgz",
+      "integrity": "sha512-wa7YjyUGfNZngI/vtK0UHAN+lgDCxBPCylVXGp0zu59Fz5aiGtNXaq3DhIov063MorB+VfufLh3JlF2KdTK3xg==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/vite": {
       "version": "5.3.4",
       "license": "MIT",
@@ -7802,6 +7937,16 @@
         "url": "https://github.com/sponsors/ota-meshi"
       }
     },
+    "node_modules/yn": {
+      "version": "3.1.1",
+      "resolved": "https://registry.npmjs.org/yn/-/yn-3.1.1.tgz",
+      "integrity": "sha512-Ux4ygGWsu2c7isFWe8Yu1YluJmqVhxqK2cLXNQA5AcC3QfbGNpM7fu0Y8b/z16pXLnFxZYvWhd3fhBY9DLmC6Q==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">=6"
+      }
+    },
     "node_modules/yocto-queue": {
       "version": "0.1.0",
       "dev": true,
diff --git a/src/Resources/package.json b/src/Resources/package.json
index b55107621..4b12d89ba 100644
--- a/src/Resources/package.json
+++ b/src/Resources/package.json
@@ -58,6 +58,7 @@
     "prettier": "^3.2.5",
     "prettier-plugin-tailwindcss": "^0.6.5",
     "tailwindcss": "^3.4.6",
+    "ts-node": "^10.9.2",
     "typescript": "^5.4.0",
     "vite": "^5.3.1",
     "vite-plugin-vue-devtools": "^7.3.1",
diff --git a/src/Resources/src/components/balance/BalanceHeader.vue b/src/Resources/src/components/balance/BalanceHeader.vue
index 0afc3d4ff..b736ac025 100644
--- a/src/Resources/src/components/balance/BalanceHeader.vue
+++ b/src/Resources/src/components/balance/BalanceHeader.vue
@@ -10,7 +10,7 @@
         :translate-x-min="'-18%'"
         class="m-auto w-fit"
       >
-        <template #button="{ open }">
+        <template>
           <button
             class="hover:bg-highlight-2 btn-highlight-shadow mx-2 mb-6 mt-4 h-9 items-center rounded-btn bg-highlight px-[34px] text-center text-btn font-bold text-white shadow-btn drop-shadow-btn transition-all duration-300 ease-out active:translate-y-0.5 active:shadow-btn-active"
           >
diff --git a/src/Resources/src/components/balance/TransactionPanel.vue b/src/Resources/src/components/balance/TransactionPanel.vue
index e4b56ee09..2dbf842d3 100644
--- a/src/Resources/src/components/balance/TransactionPanel.vue
+++ b/src/Resources/src/components/balance/TransactionPanel.vue
@@ -23,7 +23,7 @@
 
 <script setup lang="ts">
 import { RadarSpinner } from 'epic-spinners';
-import { loadScript, type PayPalNamespace } from '@paypal/paypal-js';
+import { loadScript } from '@paypal/paypal-js';
 import { transactionStore } from '@/stores/transactionStore';
 import { useI18n } from 'vue-i18n';
 import { type WatchStopHandle, computed, onMounted, onUnmounted, ref, watch } from 'vue';
@@ -59,7 +59,7 @@ onMounted(async () => {
 
     if (paypal && paypal.Buttons) {
       paypal.Buttons({
-          onInit: function (data, actions) {
+          onInit: function (_data, actions) {
             periodicFetchActive.value = true;
             if (amountFieldValue.value > 0.0) {
               actions.enable();
@@ -78,7 +78,7 @@ onMounted(async () => {
               }
             );
           },
-          createOrder: function (data, actions) {
+          createOrder: function (_data, actions) {
             checkActiveSession();
             return actions.order.create({
               purchase_units: [
@@ -92,7 +92,7 @@ onMounted(async () => {
               intent: 'CAPTURE'
             });
           },
-          onShippingChange: function (data, actions) {
+          onShippingChange: function (_data, actions) {
             return actions.resolve();
           },
           onApprove: async function (data, actions) {
diff --git a/src/Resources/src/components/categories/CategoriesActions.vue b/src/Resources/src/components/categories/CategoriesActions.vue
index a900f4bd2..5172a3c15 100644
--- a/src/Resources/src/components/categories/CategoriesActions.vue
+++ b/src/Resources/src/components/categories/CategoriesActions.vue
@@ -1,7 +1,7 @@
 <template>
   <div class="flex flex-row content-center items-center justify-end justify-items-end sm:gap-4">
     <Popover :translate-x-min="'-50%'">
-      <template #button="{ open }">
+      <template>
         <ActionButton
           :action="Action.EDIT"
           :btn-text="t('button.edit')"
diff --git a/src/Resources/src/components/costs/CostsTableActions.vue b/src/Resources/src/components/costs/CostsTableActions.vue
index b820cbb7d..e7d8883ea 100644
--- a/src/Resources/src/components/costs/CostsTableActions.vue
+++ b/src/Resources/src/components/costs/CostsTableActions.vue
@@ -11,7 +11,7 @@
       :translate-x-min="'-5%'"
       :popup-styles="'right-0'"
     >
-      <template #button="{ open }">
+      <template>
         <ActionButton
           :action="Action.CREATE"
           :btn-text="''"
diff --git a/src/Resources/src/components/dashboard/CombiButtonGroup.vue b/src/Resources/src/components/dashboard/CombiButtonGroup.vue
index 2dc297da9..7dbe98696 100644
--- a/src/Resources/src/components/dashboard/CombiButtonGroup.vue
+++ b/src/Resources/src/components/dashboard/CombiButtonGroup.vue
@@ -56,6 +56,13 @@ import { RadioGroup, RadioGroupDescription, RadioGroupLabel, RadioGroupOption }
 import { dashboardStore } from '@/stores/dashboardStore';
 import { type Meal } from '@/api/getDashboardData';
 
+interface DishInfo {
+  id: string | number,
+  title: string,
+  description: string,
+  slug: string
+}
+
 const props = defineProps<{
   weekID: number | string;
   dayID: number | string;
@@ -63,28 +70,28 @@ const props = defineProps<{
   meal: Meal;
 }>();
 
-const meal = props.meal !== undefined ? props.meal : dashboardStore.getMeal(props.weekID, props.dayID, props.mealID);
+const meal = props.meal ?? dashboardStore.getMeal(props.weekID, props.dayID, props.mealID);
 const emit = defineEmits(['addEntry', 'removeEntry']);
 const selected = ref();
-let dishes = [];
+let dishes: DishInfo[] = [];
 let oldSlug = '';
 
 if (meal.variations) {
   for (const variationID in meal.variations) {
     dishes.push({
-      id: variationID,
+      id: parseInt(String(variationID)),
       title: meal.title.en,
       description: meal.variations[variationID].title.en,
-      slug: meal.variations[variationID].dishSlug
+      slug: meal.variations[variationID].dishSlug ?? ''
     });
   }
   selected.value = dishes[0];
 } else {
   dishes.push({
-    id: props.mealID,
+    id: parseInt(String(props.mealID)),
     title: meal.title.en,
-    description: meal.description.en,
-    slug: meal.dishSlug
+    description: meal.description?.en ?? '',
+    slug: meal.dishSlug ?? ''
   });
   selected.value = meal.dishSlug;
   emit('addEntry', meal.dishSlug);
diff --git a/src/Resources/src/components/dashboard/DashboardWeekAll.vue b/src/Resources/src/components/dashboard/DashboardWeekAll.vue
index 624e7cad6..c80f83f18 100644
--- a/src/Resources/src/components/dashboard/DashboardWeekAll.vue
+++ b/src/Resources/src/components/dashboard/DashboardWeekAll.vue
@@ -1,7 +1,7 @@
 <template>
   <div class="inline-flex divide-x-2 print:block print:h-screen">
     <div
-      v-for="(week, weekID, index) in weeks"
+      v-for="(weekID, index) in Object.keys(weeks)"
       :key="index"
       class="w-[585px] flex-initial print:mx-auto print:w-full print:last:hidden"
     >
diff --git a/src/Resources/src/components/dashboard/DashboardWeekTabs.vue b/src/Resources/src/components/dashboard/DashboardWeekTabs.vue
index 04e72665e..f86aa4829 100644
--- a/src/Resources/src/components/dashboard/DashboardWeekTabs.vue
+++ b/src/Resources/src/components/dashboard/DashboardWeekTabs.vue
@@ -4,7 +4,7 @@
     class="tabs mb-5 justify-center gap-4"
   >
     <tab
-      v-for="(week, weekID, index) in weeks"
+      v-for="(weekID, index) in Object.keys(weeks)"
       :key="`t${String(weekID)}`"
       :val="weekID"
       :label="t('dashboard.' + index)"
@@ -26,7 +26,7 @@
     :swipeable="true"
   >
     <tab-panel
-      v-for="(week, weekID, index) in weeks"
+      v-for="(weekID, index) in Object.keys(weeks)"
       :key="`tp${String(weekID)}`"
       :val="weekID"
     >
diff --git a/src/Resources/src/components/dashboard/Day.vue b/src/Resources/src/components/dashboard/Day.vue
index ecd6ae774..5bdf846f8 100644
--- a/src/Resources/src/components/dashboard/Day.vue
+++ b/src/Resources/src/components/dashboard/Day.vue
@@ -99,7 +99,6 @@
 </template>
 
 <script setup lang="ts">
-import { type GuestDay } from '@/api/getInvitationData';
 import GuestButton from '@/components/dashboard/GuestButton.vue';
 import InformationButton from '@/components/dashboard/InformationButton.vue';
 import MealData from '@/components/dashboard/MealData.vue';
diff --git a/src/Resources/src/components/dashboard/GuestLink.vue b/src/Resources/src/components/dashboard/GuestLink.vue
index 42771bad7..0f3222b70 100644
--- a/src/Resources/src/components/dashboard/GuestLink.vue
+++ b/src/Resources/src/components/dashboard/GuestLink.vue
@@ -27,7 +27,7 @@ const url = ref('');
 onMounted(async () => {
   const { link, error } =
     props.invitation === Invitation.MEAL ? await useGuestLink(props.dayID) : await getEventGuestLink(props.dayID);
-  if (error.value === false) {
+  if (error.value === false && link.value !== undefined) {
     copyTextToClipboard(link.value.url);
     url.value = link.value.url;
   }
diff --git a/src/Resources/src/components/dashboard/MealCheckbox.vue b/src/Resources/src/components/dashboard/MealCheckbox.vue
index 56c3c75e5..b37b92273 100644
--- a/src/Resources/src/components/dashboard/MealCheckbox.vue
+++ b/src/Resources/src/components/dashboard/MealCheckbox.vue
@@ -107,6 +107,7 @@ const checkboxCSS = computed(() => {
         return cssResult;
       case MealState.OFFERING:
         cssResult += 'bg-highlight cursor-pointer border-0';
+        return cssResult;
       case MealState.OFFERABLE:
         cssResult += 'bg-primary-4 cursor-pointer border-0';
         return cssResult;
diff --git a/src/Resources/src/components/dashboard/MealData.vue b/src/Resources/src/components/dashboard/MealData.vue
index 51f483f9b..e68a0340b 100644
--- a/src/Resources/src/components/dashboard/MealData.vue
+++ b/src/Resources/src/components/dashboard/MealData.vue
@@ -38,11 +38,11 @@
     <div class="text-align-last flex flex-auto basis-1/12 flex-row justify-end gap-1 min-[380px]:items-center">
       <PriceTag
         class="align-center my-auto flex print:hidden"
-        :price="meal.price"
+        :price="meal.price ?? 0"
       />
       <ParticipationCounter
         :mealCSS="mealCSS"
-        :limit="meal.limit"
+        :limit="meal.limit ?? 0"
       >
         {{ participationDisplayString }}
       </ParticipationCounter>
@@ -77,14 +77,14 @@ const props = defineProps<{
   day: Day;
 }>();
 
-const meal = props.meal ? props.meal : dashboardStore.getMeal(props.weekID, props.dayID, props.mealID);
+const meal = props.meal ?? dashboardStore.getMeal(props.weekID ?? -1, props.dayID ?? -1, props.mealID);
 
 const { t, locale } = useI18n();
 const { getCombiDishes } = useDishes();
 
 const title = computed(() => (locale.value.substring(0, 2) === 'en' ? meal.title.en : meal.title.de));
 
-const description = computed(() => (locale.value.substring(0, 2) === 'en' ? meal.description.en : meal.description.de));
+const description = computed(() => (locale.value.substring(0, 2) === 'en' ? meal.description?.en : meal.description?.de));
 const combiDescription = ref<string[]>([]);
 
 onMounted(async () => {
@@ -118,14 +118,14 @@ const mealCSS = computed(() => {
 });
 
 const participationDisplayString = computed(() => {
-  const fixedCount = Math.ceil(parseFloat(meal.participations.toFixed(1)));
-  return meal.limit > 0 ? `${fixedCount}/${meal.limit}` : fixedCount;
+  const fixedCount = Math.ceil(parseFloat((meal.participations ?? 0).toFixed(1)));
+  return (meal.limit ?? 0) > 0 ? `${fixedCount}/${meal.limit}` : fixedCount;
 });
 
 async function getCombiDescription() {
   if (props.meal.isParticipating !== null && props.meal.dishSlug === 'combined-dish' && dayHasVariations()) {
     const combiDishes = await getCombiDishes(typeof props.mealID === 'string' ? parseInt(props.mealID) : props.mealID);
-    return combiDishes.map((dish) => (locale.value === 'de' ? dish.titleDe : dish.titleEn));
+    return (combiDishes ?? []).map((dish) => (locale.value === 'de' ? dish.titleDe : dish.titleEn));
   } else {
     return [];
   }
@@ -133,7 +133,7 @@ async function getCombiDescription() {
 
 function dayHasVariations() {
   for (const meal of Object.values(props.day.meals)) {
-    if ((meal as Meal).variations && Object.values((meal as Meal).variations).length > 0) {
+    if ((meal as Meal).variations && Object.values(meal.variations ?? {}).length > 0) {
       return true;
     }
   }
diff --git a/src/Resources/src/components/dashboard/Slots.vue b/src/Resources/src/components/dashboard/Slots.vue
index 38520e4a3..7b6e2280b 100644
--- a/src/Resources/src/components/dashboard/Slots.vue
+++ b/src/Resources/src/components/dashboard/Slots.vue
@@ -35,8 +35,8 @@
           <template v-for="slot in day.slots">
             <ListboxOption
               v-if="slot.id !== 0 || !isParticipating"
-              v-slot="{ active, selected }"
-              :key="slot.slug"
+              v-slot="{ selected }"
+              :key="slot.slug ?? ''"
               :value="slot"
               as="template"
             >
@@ -117,12 +117,12 @@ if (props.dayID) {
     for (const mealId in props.day.meals) {
       if (props.day.meals[mealId].variations !== null) {
         for (const variationsId in props.day.meals[mealId].variations) {
-          if (props.day.meals[mealId].variations[variationsId].isParticipating) {
+          if (getIsParticipating(mealId, variationsId)) {
             return true;
           }
         }
       }
-      if (props.day.meals[mealId].isParticipating) {
+      if (getIsParticipating(mealId)) {
         return true;
       }
     }
@@ -133,4 +133,13 @@ if (props.dayID) {
   const { emit } = useEventsBus();
   watch(selectedSlot, () => emit('guestChosenSlot', selectedSlot.value.id));
 }
+
+function getIsParticipating(mealId: string, variationsId?: string) {
+  const meal = props.day.meals[mealId];
+  if (variationsId !== undefined && meal.variations !== null) {
+    const variation = meal.variations[variationsId];
+    return variation.isParticipating;
+  }
+  return meal.isParticipating;
+}
 </script>
diff --git a/src/Resources/src/components/dashboard/VariationsData.vue b/src/Resources/src/components/dashboard/VariationsData.vue
index 9d340f9e7..0cc15be55 100644
--- a/src/Resources/src/components/dashboard/VariationsData.vue
+++ b/src/Resources/src/components/dashboard/VariationsData.vue
@@ -6,7 +6,7 @@
     ><br />
   </div>
   <div
-    v-for="(variation, variationID, index) in meal.variations"
+    v-for="(variation, variationID, index) in meal?.variations"
     :key="index"
     class="mb-1.5 flex w-auto flex-col justify-around gap-1 last:mb-0 min-[380px]:flex-row min-[380px]:gap-2 xl:grid-cols-6"
   >
@@ -45,11 +45,11 @@
     >
       <PriceTag
         class="align-center my-auto flex print:hidden"
-        :price="variation.price"
+        :price="variation.price ?? 0"
       />
       <ParticipationCounter
-        :limit="variation.limit"
-        :mealCSS="mealCSS[String(variationID)]"
+        :limit="variation.limit ?? 0"
+        :mealCSS="mealCSS.get(String(variationID)) ?? ''"
       >
         {{ getParticipationDisplayString(variation) }}
       </ParticipationCounter>
@@ -77,6 +77,7 @@ import PriceTag from '@/components/dashboard/PriceTag.vue';
 import { type Day, type Meal } from '@/api/getDashboardData';
 import VeggiIcon from '@/components/misc/VeggiIcon.vue';
 import { Diet } from '@/enums/Diet';
+import { MealState } from '@/enums/MealState';
 
 const { receive } = useEventsBus();
 
@@ -92,27 +93,25 @@ const props = defineProps<{
 
 const meal = props.meal ? props.meal : dashboardStore.getMeal(props.weekID, props.dayID, props.mealID);
 
-const parentTitle = computed(() => (locale.value.substring(0, 2) === 'en' ? meal.title.en : meal.title.de));
+const parentTitle = computed(() => (locale.value.substring(0, 2) === 'en' ? meal?.title.en : meal?.title.de));
 
 const mealCSS = computed(() => {
-  const array: string[] = [];
-  for (const variationId in meal.variations) {
-    array[variationId] = 'flex content-center rounded-md h-[30px] xl:h-[20px] ';
-    switch (meal.variations[variationId].mealState) {
-      case 'disabled':
-      case 'offerable':
-        array[variationId] += 'bg-[#80909F]';
+  const css : Map<string, string> = new Map();
+  for (const variation of Object.values(meal?.variations ?? {})) {
+    let cssStr = 'flex content-center rounded-md h-[30px] xl:h-[20px] ';
+    switch (variation.mealState) {
+      case MealState.DISABLED, MealState.OFFERABLE:
+        cssStr += 'bg-[#80909F]';
         break;
-      case 'open':
-        array[variationId] += 'bg-primary-4';
+      case MealState.OPEN:
+        cssStr += 'bg-primary-4';
         break;
-      case 'tradeable':
-      case 'offering':
-        array[variationId] += 'bg-highlight';
+      case MealState.TRADEABLE, MealState.OFFERING:
+        cssStr += 'bg-highlight';
         break;
     }
   }
-  return array;
+  return css;
 });
 
 const openPopover = ref(false);
@@ -123,8 +122,8 @@ receive('openOfferPanel_' + props.mealID, () => {
 });
 
 const getParticipationDisplayString = (variation: Meal) => {
-  const fixedCount = Math.ceil(parseFloat(variation.participations.toFixed(1)));
-  return variation.limit > 0 ? `${fixedCount}/${variation.limit}` : fixedCount;
+  const fixedCount = Math.ceil(parseFloat((variation.participations ?? 0).toFixed(1)));
+  return (variation.limit ?? 0) > 0 ? `${fixedCount}/${variation.limit}` : fixedCount;
 };
 </script>
 
diff --git a/src/Resources/src/components/dashboard/Week.vue b/src/Resources/src/components/dashboard/Week.vue
index 283917831..f445fc8a6 100644
--- a/src/Resources/src/components/dashboard/Week.vue
+++ b/src/Resources/src/components/dashboard/Week.vue
@@ -24,7 +24,7 @@
     class="grid"
   >
     <Day
-      v-for="(day, dayID, d_index) in days"
+      v-for="(dayID, d_index) in Object.keys(days ?? {})"
       :key="dayID"
       :weekID="String(weekID)"
       :dayID="String(dayID)"
diff --git a/src/Resources/src/components/dishes/DishActions.vue b/src/Resources/src/components/dishes/DishActions.vue
index 9818a91cb..129e292d7 100644
--- a/src/Resources/src/components/dishes/DishActions.vue
+++ b/src/Resources/src/components/dishes/DishActions.vue
@@ -5,7 +5,7 @@
       :translate-x-min="'-5%'"
       :translate-x-max="'-5%'"
     >
-      <template #button="{ open }">
+      <template>
         <ActionButton
           :action="Action.CREATE"
           :btn-text="t('dish.popover.variation.new')"
@@ -24,7 +24,7 @@
       :translate-x-min="'-5%'"
       :translate-x-max="'-5%'"
     >
-      <template #button="{ open }">
+      <template>
         <ActionButton
           :action="Action.EDIT"
           :btn-text="t('button.edit')"
diff --git a/src/Resources/src/components/dishes/DishVariationActions.vue b/src/Resources/src/components/dishes/DishVariationActions.vue
index cd0c3ddf5..a7c7d1e8b 100644
--- a/src/Resources/src/components/dishes/DishVariationActions.vue
+++ b/src/Resources/src/components/dishes/DishVariationActions.vue
@@ -5,7 +5,7 @@
       :translate-x-min="'-5%'"
       :translate-x-max="'-5%'"
     >
-      <template #button="{ open }">
+      <template>
         <ActionButton
           :action="Action.EDIT"
           :btn-text="t('button.edit')"
diff --git a/src/Resources/src/components/events/EventsActions.vue b/src/Resources/src/components/events/EventsActions.vue
index 02709016e..0abf26aaf 100644
--- a/src/Resources/src/components/events/EventsActions.vue
+++ b/src/Resources/src/components/events/EventsActions.vue
@@ -1,7 +1,7 @@
 <template>
   <div class="flex flex-row content-center items-center justify-end justify-items-end sm:gap-4">
     <Popover :translate-x-min="'-71%'">
-      <template #button="{ open }">
+      <template>
         <ActionButton
           :action="Action.EDIT"
           :btn-text="t('button.edit')"
diff --git a/src/Resources/src/components/menu/EventInput.vue b/src/Resources/src/components/menu/EventInput.vue
index c6a1dfd77..749a79686 100644
--- a/src/Resources/src/components/menu/EventInput.vue
+++ b/src/Resources/src/components/menu/EventInput.vue
@@ -1,6 +1,5 @@
 <template>
   <Combobox
-    v-slot="{ open }"
     v-model="value"
     as="span"
     class="relative w-full"
diff --git a/src/Resources/src/components/menu/MenuDay.vue b/src/Resources/src/components/menu/MenuDay.vue
index 4f60b6e98..9c882913a 100644
--- a/src/Resources/src/components/menu/MenuDay.vue
+++ b/src/Resources/src/components/menu/MenuDay.vue
@@ -9,7 +9,7 @@
         :translate-x-min="'0%'"
         :translate-x-max="'-5%'"
       >
-        <template #button="{ open }">
+        <template>
           <UserIcon
             class="row-start-1 size-5 cursor-pointer"
             :class="participationLimitNotZero ? 'text-highlight' : 'text-white'"
diff --git a/src/Resources/src/components/menu/MenuInput.vue b/src/Resources/src/components/menu/MenuInput.vue
index 40c224f38..f79ccfd9e 100644
--- a/src/Resources/src/components/menu/MenuInput.vue
+++ b/src/Resources/src/components/menu/MenuInput.vue
@@ -1,6 +1,5 @@
 <template>
   <Combobox
-    v-slot="{ open }"
     v-model="selectedDish"
     as="span"
     class="relative w-full"
@@ -20,7 +19,7 @@
           :fill-colour="'fill-[#9CA3AF]'"
         />
         <ComboboxInput
-          :displayValue="(dish) => titleStringRepr"
+          :displayValue="() => titleStringRepr"
           class="w-full truncate border-none px-4 py-2 text-[#9CA3AF] focus:outline-none"
           @change="setFilter($event.target.value)"
         />
diff --git a/src/Resources/src/components/menu/MenuLockDatePicker.vue b/src/Resources/src/components/menu/MenuLockDatePicker.vue
index bbe366cf8..b8e0ff164 100644
--- a/src/Resources/src/components/menu/MenuLockDatePicker.vue
+++ b/src/Resources/src/components/menu/MenuLockDatePicker.vue
@@ -3,7 +3,7 @@
     :translate-x-max="'-5%'"
     :translate-x-min="'0%'"
   >
-    <template #button="{ open }">
+    <template>
       <CalendarIcon
         class="size-5 cursor-pointer"
         :class="isStandardLockDate ? 'text-white' : 'text-highlight'"
diff --git a/src/Resources/src/components/menuParticipants/AddParticipantsSearchBar.vue b/src/Resources/src/components/menuParticipants/AddParticipantsSearchBar.vue
index b62c447f7..57985ff71 100644
--- a/src/Resources/src/components/menuParticipants/AddParticipantsSearchBar.vue
+++ b/src/Resources/src/components/menuParticipants/AddParticipantsSearchBar.vue
@@ -1,6 +1,5 @@
 <template>
   <Combobox
-    v-slot="{ open }"
     v-model="selectedProfile"
     as="span"
     class="relative w-full"
diff --git a/src/Resources/src/components/menuParticipants/MenuTableHead.vue b/src/Resources/src/components/menuParticipants/MenuTableHead.vue
index d21225141..76e11bfe1 100644
--- a/src/Resources/src/components/menuParticipants/MenuTableHead.vue
+++ b/src/Resources/src/components/menuParticipants/MenuTableHead.vue
@@ -29,7 +29,7 @@
           class="sticky left-0 top-0 z-40 whitespace-nowrap border-b-2 border-r-2 border-solid border-gray-200 bg-[#f4f7f9] px-4 py-2 text-start"
         />
       </template>
-      <template #dayMeals="{ dayId, meals }">
+      <template #dayMeals="{ meals }">
         <th
           v-for="(meal, mealIndex) in meals"
           :key="`${String(meal.id)}_${String(mealIndex)}`"
diff --git a/src/Resources/src/components/navbar/MobileDropdown3.vue b/src/Resources/src/components/navbar/MobileDropdown3.vue
index edc14f040..77cc48b33 100644
--- a/src/Resources/src/components/navbar/MobileDropdown3.vue
+++ b/src/Resources/src/components/navbar/MobileDropdown3.vue
@@ -112,7 +112,7 @@ import { MenuItems, MenuItem } from '@headlessui/vue';
 import { CurrencyEuroIcon } from '@heroicons/vue/outline';
 import { useI18n } from 'vue-i18n';
 import Icons from '../misc/Icons.vue';
-import { INavigation } from '@/interfaces/INavigation';
+import { type INavigation } from '@/interfaces/INavigation';
 
 const { t, locale } = useI18n();
 
diff --git a/src/Resources/src/components/participations/ParticipantsListByDay.vue b/src/Resources/src/components/participations/ParticipantsListByDay.vue
index d5330d237..4440ac992 100644
--- a/src/Resources/src/components/participations/ParticipantsListByDay.vue
+++ b/src/Resources/src/components/participations/ParticipantsListByDay.vue
@@ -21,7 +21,7 @@
     <table :class="'w-full scroll-m-0.5 overflow-y-scroll'">
       <tbody>
         <template
-          v-for="(participant, index) in filteredParticipants"
+          v-for="participant in filteredParticipants"
           :key="index"
         >
           <tr :class="[0 ? 'border-gray-300' : 'border-gray-200', 'border-b']">
diff --git a/src/Resources/src/components/participations/ParticipantsTableData.vue b/src/Resources/src/components/participations/ParticipantsTableData.vue
index 1f318afbf..c215742b1 100644
--- a/src/Resources/src/components/participations/ParticipantsTableData.vue
+++ b/src/Resources/src/components/participations/ParticipantsTableData.vue
@@ -4,7 +4,7 @@
     class="flex flex-row items-stretch"
   >
     <div
-      v-for="(variation, index) in meal.variations"
+      v-for="variation in meal.variations"
       :key="variation.mealId"
       class="variations-class min-h-[24px] flex-1 border-l text-center"
     >
diff --git a/src/Resources/src/components/printableList/PrintListPdfTemplate.vue b/src/Resources/src/components/printableList/PrintListPdfTemplate.vue
index 005194b9a..575544efa 100644
--- a/src/Resources/src/components/printableList/PrintListPdfTemplate.vue
+++ b/src/Resources/src/components/printableList/PrintListPdfTemplate.vue
@@ -81,7 +81,7 @@
                         {{ String(participantName) }}
                       </td>
                       <td
-                        v-for="(meal, mealId) in listData.meals"
+                        v-for="mealId in Object.keys(listData.meals)"
                         :key="`${index}${String(mealId)}`"
                         class="whitespace-nowrap px-3 py-4 text-center text-[18px]/[24px] text-gray-500"
                       >
diff --git a/src/Resources/src/components/timeslots/SlotActions.vue b/src/Resources/src/components/timeslots/SlotActions.vue
index 7ebd3af31..916d2dddd 100644
--- a/src/Resources/src/components/timeslots/SlotActions.vue
+++ b/src/Resources/src/components/timeslots/SlotActions.vue
@@ -4,7 +4,7 @@
       :translate-x-max="'-30%'"
       :translate-x-min="'-30%'"
     >
-      <template #button="{ open }">
+      <template>
         <ActionButton
           :action="Action.EDIT"
           :btn-text="t('button.edit')"
diff --git a/src/Resources/src/stores/categoriesStore.ts b/src/Resources/src/stores/categoriesStore.ts
index eb2a769a4..f5b75589d 100644
--- a/src/Resources/src/stores/categoriesStore.ts
+++ b/src/Resources/src/stores/categoriesStore.ts
@@ -3,7 +3,7 @@ import getCategoriesData from '@/api/getCategoriesData';
 import deleteCategory from '@/api/deleteCategory';
 import postCreateCategory from '@/api/postCreateCategory';
 import putCategoryUpdate from '@/api/putCategoryUpdate';
-import { isMessage } from '@/interfaces/IMessage';
+import { isMessage, type IMessage } from '@/interfaces/IMessage';
 import { isResponseObjectOkay, isResponseArrayOkay } from '@/api/isResponseOkay';
 import useFlashMessage from '@/services/useFlashMessage';
 import { FlashMessageType } from '@/enums/FlashMessage';
@@ -73,7 +73,7 @@ export function useCategories() {
         const { categories, error } = await getCategoriesData();
 
         if (isResponseArrayOkay<Category>(error, categories, isCategory) === true) {
-            CategoriesState.categories = categories.value;
+            CategoriesState.categories = (categories.value as Category[]);
             CategoriesState.error = '';
         } else {
             setTimeout(fetchCategories, TIMEOUT_PERIOD);
@@ -89,7 +89,7 @@ export function useCategories() {
         const { error, response } = await deleteCategory(slug);
 
         if (error.value === true || isMessage(response.value) === true) {
-            CategoriesState.error = response.value?.message;
+            CategoriesState.error = (response.value as IMessage).message;
             return;
         }
 
@@ -108,7 +108,7 @@ export function useCategories() {
         const { error, response } = await postCreateCategory(newCategory);
 
         if (error.value === true || isMessage(response.value) === true) {
-            CategoriesState.error = response.value?.message;
+            CategoriesState.error = (response.value as IMessage).message;
             return;
         }
 
diff --git a/src/Resources/src/stores/dishesStore.ts b/src/Resources/src/stores/dishesStore.ts
index 324f4b8ea..659570e47 100644
--- a/src/Resources/src/stores/dishesStore.ts
+++ b/src/Resources/src/stores/dishesStore.ts
@@ -359,7 +359,7 @@ export function useDishes() {
      * @param slugs The slugs of the dishes to return
      */
     function getDishArrayBySlugs(slugs: string[]) {
-        const dishesFromSlugs: Dish[] = slugs.map((slug) => getDishBySlug(slug)).filter(dish => dish !== null && dish !== undefined);
+        const dishesFromSlugs: Dish[] = slugs.map((slug) => getDishBySlug(slug)).filter(dish => dish !== null && dish !== undefined) as Dish[];
 
         const dishesWithParent: Dish[] = [];
 
diff --git a/src/Resources/src/tools/mercureReceiver.ts b/src/Resources/src/tools/mercureReceiver.ts
index 255b9f67b..f92f548b2 100644
--- a/src/Resources/src/tools/mercureReceiver.ts
+++ b/src/Resources/src/tools/mercureReceiver.ts
@@ -103,9 +103,11 @@ class MercureReceiver {
 
     private static async handleParticipationUpdate(data: Meal_Update): Promise<void> {
         for (const mealData of data.meals) {
-            const meal: Meal = this.getMealToUpdate(mealData, data);
-            this.setMealAttributes(meal, mealData);
-            this.setMealState(data, mealData, meal);
+            const meal: Meal | undefined = this.getMealToUpdate(mealData, data);
+            if (meal !== undefined) {
+                this.setMealAttributes(meal, mealData);
+                this.setMealState(data, mealData, meal);
+            }
         }
         removeLock(String(data.dayId));
     }
@@ -183,7 +185,7 @@ class MercureReceiver {
         if (data.participant === userDataStore.getState().fullname) {
             const { error, response } = await getIsParticipating(mealData.mealId);
             if (meal !== undefined && error.value === false) {
-                meal.isParticipating = response.value;
+                meal.isParticipating = response.value ?? null;
                 meal.mealState = generateMealState(meal);
             }
         }
diff --git a/src/Resources/src/views/PrintableList.vue b/src/Resources/src/views/PrintableList.vue
index 0a6548274..fb9933e5a 100644
--- a/src/Resources/src/views/PrintableList.vue
+++ b/src/Resources/src/views/PrintableList.vue
@@ -80,7 +80,7 @@
                       {{ String(participantName) }}
                     </td>
                     <td
-                      v-for="(meal, mealId) in listData.meals"
+                      v-for="mealId in Object.keys(listData.meals)"
                       :key="`${index}${String(mealId)}`"
                       class="whitespace-nowrap px-3 py-4 text-center text-sm text-gray-500"
                     >
diff --git a/src/Resources/tsconfig.app.json b/src/Resources/tsconfig.app.json
index e14c754d3..84bae3fcc 100644
--- a/src/Resources/tsconfig.app.json
+++ b/src/Resources/tsconfig.app.json
@@ -3,8 +3,30 @@
   "include": ["env.d.ts", "src/**/*", "src/**/*.vue"],
   "exclude": ["src/**/__tests__/*"],
   "compilerOptions": {
+    "allowJs": false,
+    "allowUnreachableCode": false,
+    "alwaysStrict": true,
     "composite": true,
-    "tsBuildInfoFile": "./node_modules/.tmp/tsconfig.app.tsbuildinfo",
+    "esModuleInterop": true,
+    "experimentalDecorators": true,
+    "forceConsistentCasingInFileNames": true,
+    "jsx": "preserve",
+    "lib": ["ES2022", "DOM"],
+    "noEmit": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true,
+    "noFallthroughCasesInSwitch": true,
+    "module": "ES2022",
+    "moduleResolution": "Bundler",
+    "skipLibCheck": true,
+    "resolveJsonModule": true,
+    "sourceMap": true,
+    "strict": true,
+    "tsBuildInfoFile": "./node_modules/.tmp/tsconfig.node.tsbuildinfo",
+    "target": "ES2022",
+    "types": ["node"],
+    "typeRoots": ["./node_modules/@types", "./src/types"],
+    "useDefineForClassFields": true,
 
     "baseUrl": ".",
     "paths": {
diff --git a/src/Resources/tsconfig.node.json b/src/Resources/tsconfig.node.json
index eb0e8601c..172134e31 100644
--- a/src/Resources/tsconfig.node.json
+++ b/src/Resources/tsconfig.node.json
@@ -13,13 +13,11 @@
     "alwaysStrict": true,
     "composite": true,
     "esModuleInterop": true,
-    "exactOptionalPropertyTypes": true,
     "experimentalDecorators": true,
     "forceConsistentCasingInFileNames": true,
     "jsx": "preserve",
-    "lib": ["ES2022"],
+    "lib": ["ES2022", "DOM"],
     "noEmit": true,
-    "noImplicitReturns": true,
     "noUnusedLocals": true,
     "noUnusedParameters": true,
     "noFallthroughCasesInSwitch": true,