diff --git a/packages/backend/src/db/seed.ts b/packages/backend/src/db/seed.ts
index db2a9bd..ceb8166 100644
--- a/packages/backend/src/db/seed.ts
+++ b/packages/backend/src/db/seed.ts
@@ -3,11 +3,11 @@ import { cards, lessons } from './schema.js';
 
 const { db, sqlite } = createDb();
 const [root] = db.insert(lessons).values({ name: 'Demo: Spaans', position: 0 }).returning().all();
-const [sub] = db.insert(lessons).values({ name: 'Begroetingen', parentId: root.id, position: 0 }).returning().all();
+const [sub] = db.insert(lessons).values({ name: 'Begroetingen', parentId: root!.id, position: 0 }).returning().all();
 db.insert(cards).values([
-  { lessonId: sub.id, question: 'Hallo', answer: 'Hola', position: 0 },
-  { lessonId: sub.id, question: 'Goedemorgen', answer: 'Buenos días', position: 1 },
-  { lessonId: sub.id, question: 'Tot ziens', answer: 'Adiós', position: 2 },
+  { lessonId: sub!.id, question: 'Hallo', answer: 'Hola', position: 0 },
+  { lessonId: sub!.id, question: 'Goedemorgen', answer: 'Buenos días', position: 1 },
+  { lessonId: sub!.id, question: 'Tot ziens', answer: 'Adiós', position: 2 },
 ]).run();
 sqlite.close();
 console.log('Seed inserted.');