diff --git a/src/lib/stores/childrenStore.test.ts b/src/lib/stores/childrenStore.test.ts
new file mode 100644
index 00000000..e69de29b
diff --git a/src/lib/stores/childrenData.ts b/src/lib/stores/childrenStore.ts
similarity index 100%
rename from src/lib/stores/childrenData.ts
rename to src/lib/stores/childrenStore.ts
diff --git a/src/lib/stores/contentStore.test.ts b/src/lib/stores/contentStore.test.ts
new file mode 100644
index 00000000..e69de29b
diff --git a/src/lib/stores/userStore.test.ts b/src/lib/stores/userStore.test.ts
new file mode 100644
index 00000000..a1c0fd87
--- /dev/null
+++ b/src/lib/stores/userStore.test.ts
@@ -0,0 +1,66 @@
+// userStore.test.ts
+
+import { get } from 'svelte/store';
+import { describe, expect, it } from 'vitest';
+import { addUser, removeUser, type UserData, users } from './userStore';
+
+// Mock user data
+
+// Test suite for userStore
+describe('test_normal_function', () => {
+	const mockUserToken = 'mockUserToken';
+	const mockUserData: UserData = {
+		role: 'mockRole',
+		email: 'mockEmail',
+		name: 'mockName',
+		token: '',
+		password: 'mockPassword',
+		data: {
+			yearofbirth: 1990,
+			gender: 'male',
+			profession: 'developer',
+			education: 'bachelor',
+			workinghours: 'full-time',
+			householdincome: 'above-average'
+		}
+	};
+
+	it('should add a new user successfully', async () => {
+		users.set({});
+
+		await addUser(mockUserToken, mockUserData);
+
+		expect(get(users)[mockUserToken]).toEqual({
+			...mockUserData,
+			token: mockUserToken
+		});
+	});
+
+	it('should not add a user with an existing token', async () => {
+		users.set({ mockUserToken: mockUserData });
+
+		try {
+			await addUser(mockUserToken, mockUserData);
+		} catch (error: Error | unknown) {
+			expect((error as Error).message).toBe('User with this token already exists');
+		}
+	});
+
+	it('should remove a user successfully', async () => {
+		users.set({ mockUserToken: mockUserData });
+
+		await removeUser(mockUserToken);
+
+		expect(get(users)[mockUserToken]).toBeUndefined();
+	});
+
+	it('should not remove a user with a non-existing token', async () => {
+		users.set({ mockUserToken: mockUserData });
+
+		try {
+			await removeUser('notdefined');
+		} catch (error: Error | unknown) {
+			expect((error as Error).message).toBe('User with this token does not exist');
+		}
+	});
+});
diff --git a/src/lib/stores/userData.ts b/src/lib/stores/userStore.ts
similarity index 84%
rename from src/lib/stores/userData.ts
rename to src/lib/stores/userStore.ts
index fdec63a1..5d5878ea 100644
--- a/src/lib/stores/userData.ts
+++ b/src/lib/stores/userStore.ts
@@ -40,7 +40,7 @@ const users = writable(userlist);
 async function addUser(userToken: string, userData: UserData) {
 	users.update((userlist) => {
 		if (userToken in userlist) {
-			// raise some error
+			throw new Error('User with this token already exists');
 		} else {
 			userData['token'] = userToken;
 			userlist[userToken] = userData;
@@ -53,9 +53,11 @@ async function removeUser(userToken: string) {
 	users.update((userlist) => {
 		if (userToken in userlist) {
 			delete userlist[userToken];
+		} else {
+			throw new Error('User with this token does not exist');
 		}
 		return userlist;
 	});
 }
 
-export { addUser, removeUser, users };
+export { addUser, removeUser, users, type UserData, type UserList };