diff --git a/backend/tests/integration/cart.integration.test.ts b/backend/tests/integration/cart.integration.test.ts
new file mode 100644
index 0000000..19a69c8
--- /dev/null
+++ b/backend/tests/integration/cart.integration.test.ts
@@ -0,0 +1,118 @@
+import request from 'supertest';
+import app from '../../src/app';
+import { pool } from '../../src/db';
+import { resetDb, closeDb } from './setup/testDb';
+
+beforeEach(async () => {
+  await resetDb();
+});
+
+afterAll(async () => {
+  await pool.end();
+  await closeDb();
+});
+
+async function registerAndGetAgent(email: string) {
+  const agent = request.agent(app);
+  await agent.post('/api/customers/register').send({ email, password: 'supersecret123' });
+  return agent;
+}
+
+describe('cart', () => {
+  it('adding an item to cart marks it reserved', async () => {
+    const { rows } = await pool.query(`INSERT INTO items (name, price_cents) VALUES ('Test Item', 1000) RETURNING id`);
+    const itemId = rows[0].id;
+    const agent = await registerAndGetAgent('cart1@example.com');
+
+    const addRes = await agent.post(`/api/cart/items/${itemId}`);
+    expect(addRes.status).toBe(201);
+
+    const itemCheck = await request(app).get(`/api/items/${itemId}`);
+    expect(itemCheck.body.status).toBe('reserved');
+
+    const cartRes = await agent.get('/api/cart');
+    expect(cartRes.body.items).toHaveLength(1);
+    expect(cartRes.body.items[0].item_id).toBe(itemId);
+  });
+
+  it('refuses to add an item that is already reserved', async () => {
+    const { rows } = await pool.query(`INSERT INTO items (name, price_cents) VALUES ('Test Item', 1000) RETURNING id`);
+    const itemId = rows[0].id;
+    const agentA = await registerAndGetAgent('cartA@example.com');
+    const agentB = await registerAndGetAgent('cartB@example.com');
+
+    await agentA.post(`/api/cart/items/${itemId}`);
+    const res = await agentB.post(`/api/cart/items/${itemId}`);
+    expect(res.status).toBe(409);
+  });
+
+  it('removing an item from cart releases it back to available', async () => {
+    const { rows } = await pool.query(`INSERT INTO items (name, price_cents) VALUES ('Test Item', 1000) RETURNING id`);
+    const itemId = rows[0].id;
+    const agent = await registerAndGetAgent('cart2@example.com');
+
+    await agent.post(`/api/cart/items/${itemId}`);
+    const removeRes = await agent.delete(`/api/cart/items/${itemId}`);
+    expect(removeRes.status).toBe(204);
+
+    const itemCheck = await request(app).get(`/api/items/${itemId}`);
+    expect(itemCheck.body.status).toBe('available');
+  });
+});
+
+describe('cart demo checkout', () => {
+  async function addShippingAddress(agent: any) {
+    const res = await agent.post('/api/customers/me/addresses').send({
+      fullName: 'Jane Doe',
+      addressLine1: '123 Main St',
+      city: 'Springfield',
+      state: 'IL',
+      postalCode: '62701'
+    });
+    return res.body.address.id;
+  }
+
+  it('completes a multi-item cart purchase and marks all items sold', async () => {
+    const { rows } = await pool.query(
+      `INSERT INTO items (name, price_cents) VALUES ('Item A', 1000), ('Item B', 2000) RETURNING id`
+    );
+    const [itemA, itemB] = rows;
+    const agent = await registerAndGetAgent('checkout1@example.com');
+
+    await agent.post(`/api/cart/items/${itemA.id}`);
+    await agent.post(`/api/cart/items/${itemB.id}`);
+    const addressId = await addShippingAddress(agent);
+
+    const res = await agent.post('/api/checkout/cart/demo/purchase').send({ shippingAddressId: addressId });
+    expect(res.status).toBe(200);
+    expect(res.body.status).toBe('completed');
+
+    const checkA = await request(app).get(`/api/items/${itemA.id}`);
+    const checkB = await request(app).get(`/api/items/${itemB.id}`);
+    expect(checkA.body.status).toBe('sold');
+    expect(checkB.body.status).toBe('sold');
+
+    const cartRes = await agent.get('/api/cart');
+    expect(cartRes.body.items).toHaveLength(0);
+
+    const ordersRes = await agent.get('/api/customers/me/orders');
+    expect(ordersRes.body).toHaveLength(2);
+  });
+
+  it('refuses checkout without a shipping address', async () => {
+    const { rows } = await pool.query(`INSERT INTO items (name, price_cents) VALUES ('Item A', 1000) RETURNING id`);
+    const agent = await registerAndGetAgent('checkout2@example.com');
+    await agent.post(`/api/cart/items/${rows[0].id}`);
+
+    const res = await agent.post('/api/checkout/cart/demo/purchase').send({});
+    expect(res.status).toBe(400);
+  });
+
+  it('refuses checkout with an empty cart', async () => {
+    const agent = await registerAndGetAgent('checkout3@example.com');
+    const addressId = await addShippingAddress(agent);
+
+    const res = await agent.post('/api/checkout/cart/demo/purchase').send({ shippingAddressId: addressId });
+    expect(res.status).toBe(400);
+  });
+});
\ No newline at end of file
diff --git a/backend/tests/integration/items.integration.test.ts b/backend/tests/integration/items.integration.test.ts
deleted file mode 100755
index 4b2583e..0000000
--- a/backend/tests/integration/items.integration.test.ts
+++ /dev/null
@@ -1,66 +0,0 @@
-import request from 'supertest';
-import app from '../../src/app';
-import { pool } from '../../src/db';
-import { resetDb, closeDb } from './setup/testDb';
-
-beforeEach(async () => {
-  await resetDb();
-});
-
-afterAll(async () => {
-  await pool.end();
-  await closeDb();
-});
-
-describe('GET /api/items', () => {
-  it('returns an empty array when there are no items', async () => {
-    const res = await request(app).get('/api/items');
-    expect(res.status).toBe(200);
-    expect(res.body).toEqual([]);
-  });
-
-  it('returns items with an empty images array when none are attached', async () => {
-    await pool.query(
-      `INSERT INTO items (name, description, price_cents) VALUES ('Vintage Lamp', 'A one-of-a-kind lamp.', 4500)`
-    );
-    const res = await request(app).get('/api/items');
-    expect(res.status).toBe(200);
-    expect(res.body).toHaveLength(1);
-    expect(res.body[0]).toMatchObject({
-      name: 'Vintage Lamp',
-      price_cents: 4500,
-      status: 'available',
-      images: []
-    });
-  });
-
-  it('returns 404 for a nonexistent item', async () => {
-    const res = await request(app).get('/api/items/99999');
-    expect(res.status).toBe(404);
-  });
-});
-
-describe('demo checkout', () => {
-  it('marks an available item as sold', async () => {
-    const { rows } = await pool.query(
-      `INSERT INTO items (name, price_cents) VALUES ('Test Item', 1000) RETURNING id`
-    );
-    const itemId = rows[0].id;
-
-    const res = await request(app).post(`/api/checkout/demo/${itemId}/purchase`);
-    expect(res.status).toBe(200);
-    expect(res.body.status).toBe('sold');
-
-    const check = await request(app).get(`/api/items/${itemId}`);
-    expect(check.body.status).toBe('sold');
-  });
-
-  it('refuses to sell an item that is already sold', async () => {
-    const { rows } = await pool.query(
-      `INSERT INTO items (name, price_cents, status) VALUES ('Already Sold', 1000, 'sold') RETURNING id`
-    );
-    const itemId = rows[0].id;
-    const res = await request(app).post(`/api/checkout/demo/${itemId}/purchase`);
-    expect(res.status).toBe(409);
-  });
-});