diff --git a/backend/__tests__/integration/crmSchema.test.js b/backend/__tests__/integration/crmSchema.test.js
new file mode 100644
index 00000000..fde94cad
--- /dev/null
+++ b/backend/__tests__/integration/crmSchema.test.js
@@ -0,0 +1,116 @@
+/**
+ * Schema-shape regression net for the CRM consolidated migration.
+ *
+ * Pins the table/column layout that the route + service layer expect
+ * after `migrations/core/107_crm_consolidated.js` runs. The schema-
+ * drift workflow (#530) catches Postgres-only FK ordering bugs (the
+ * forward-reference deferral added in this PR), but it doesn't notice
+ * if a future edit silently drops a column the service code reads —
+ * SQLite would just return undefined and the broken behavior would
+ * land on beta.
+ *
+ * Touches the lineage chain (deal_uuid + back-pointer FKs) explicitly
+ * so a rename or removal there fails the test instead of silently
+ * breaking the lineage card.
+ */
+
+const { bootCrmDb, seedMinimal } = require('./helpers/crmDb');
+
+describe('CRM schema after core migrations', () => {
+  let db;
+  let cleanup;
+
+  beforeAll(async () => {
+    ({ db, cleanup } = await bootCrmDb());
+  }, 120000);
+
+  afterAll(async () => {
+    if (cleanup) await cleanup();
+  });
+
+  describe('table layout', () => {
+    const expectedTables = [
+      'admin_users', 'customer_accounts', 'business_profile', 'business_bank_accounts',
+      'events', 'document_sequences',
+      'quotes', 'quote_line_items', 'quote_line_item_presets', 'quote_action_tokens',
+      'contracts', 'contract_blocks', 'contract_block_inclusions', 'contract_action_tokens',
+      'invoices', 'invoice_line_items', 'invoice_payment_log', 'invoice_payment_check_tokens',
+      'customer_hour_entries',
+      'payment_term_templates', 'payment_net_days_templates', 'payment_timing_templates',
+      'event_payment_plans',
+    ];
+
+    it.each(expectedTables)('has table %s', async (table) => {
+      expect(await db.schema.hasTable(table)).toBe(true);
+    });
+  });
+
+  describe('deal_uuid lineage columns', () => {
+    // Every document in one engagement shares a deal_uuid — the
+    // lineage card joins on it. Drop the column anywhere in the chain
+    // and the card silently returns partial data.
+    it.each(['quotes', 'contracts', 'invoices'])(
+      '%s has deal_uuid column',
+      async (table) => {
+        expect(await db.schema.hasColumn(table, 'deal_uuid')).toBe(true);
+      }
+    );
+
+    // The back-pointer FKs were the source of the schema-drift bug
+    // we fixed in this PR (forward references). Pin them.
+    it('quotes has converted_contract_id back-pointer', async () => {
+      expect(await db.schema.hasColumn('quotes', 'converted_contract_id')).toBe(true);
+    });
+    it('invoices has source_contract_id back-pointer', async () => {
+      expect(await db.schema.hasColumn('invoices', 'source_contract_id')).toBe(true);
+    });
+    it('invoices has source_quote_id back-pointer', async () => {
+      expect(await db.schema.hasColumn('invoices', 'source_quote_id')).toBe(true);
+    });
+  });
+
+  describe('Storno discriminator columns', () => {
+    // kind='storno' + cancels_invoice_id + negative totals are the
+    // shape every aggregate filter relies on (feedback_storno_filter_
+    // everywhere). Pin the columns so a rename doesn't silently break
+    // every revenue report.
+    it('invoices has kind discriminator', async () => {
+      expect(await db.schema.hasColumn('invoices', 'kind')).toBe(true);
+    });
+    it('invoices has cancels_invoice_id self-ref', async () => {
+      expect(await db.schema.hasColumn('invoices', 'cancels_invoice_id')).toBe(true);
+    });
+    it('invoices has replaces_invoice_id self-ref', async () => {
+      expect(await db.schema.hasColumn('invoices', 'replaces_invoice_id')).toBe(true);
+    });
+  });
+
+  describe('Event time columns (migration 137)', () => {
+    // The admin calendar reads these to render timed vs. full-day
+    // tiles. Per the feedback_migration_preserve_visuals rule, the
+    // default has to be `is_full_day=true` so existing rows keep
+    // their pre-migration visual.
+    it('events has event_time_start', async () => {
+      expect(await db.schema.hasColumn('events', 'event_time_start')).toBe(true);
+    });
+    it('events has event_time_end', async () => {
+      expect(await db.schema.hasColumn('events', 'event_time_end')).toBe(true);
+    });
+    it('events has is_full_day', async () => {
+      expect(await db.schema.hasColumn('events', 'is_full_day')).toBe(true);
+    });
+  });
+
+  describe('seed paths', () => {
+    it('admin + customer seed inserts cleanly', async () => {
+      const { adminId, customerId } = await seedMinimal(db);
+      expect(adminId).toBeTruthy();
+      expect(customerId).toBeTruthy();
+
+      const admin = await db('admin_users').where({ id: adminId }).first();
+      const customer = await db('customer_accounts').where({ id: customerId }).first();
+      expect(admin.email).toBe('tester@example.com');
+      expect(customer.email).toBe('customer@example.com');
+    });
+  });
+});
diff --git a/backend/__tests__/integration/helpers/crmDb.js b/backend/__tests__/integration/helpers/crmDb.js
new file mode 100644
index 00000000..ba51f9e6
--- /dev/null
+++ b/backend/__tests__/integration/helpers/crmDb.js
@@ -0,0 +1,121 @@
+/**
+ * Test harness for CRM integration tests.
+ *
+ * Boots a temp-SQLite database, runs every `migrations/core/*.up()`
+ * directly (bypassing knex's Migrator — its exclusive write lock
+ * deadlocks 001_init's nested `initializeDatabase()` call), and
+ * exposes a small helper for seeding the minimal row set that the
+ * quote/contract/invoice services need to operate.
+ *
+ * Usage:
+ *
+ *   const { bootCrmDb, seedMinimal } = require('./helpers/crmDb');
+ *
+ *   beforeAll(async () => {
+ *     ({ db, cleanup } = await bootCrmDb());
+ *     ({ adminId, customerId } = await seedMinimal(db));
+ *   });
+ *   afterAll(async () => { await cleanup(); });
+ */
+
+const fs = require('fs');
+const path = require('path');
+const os = require('os');
+const bcrypt = require('bcrypt');
+
+async function runCoreMigrations(db) {
+  await db.schema.createTable('migrations', (t) => {
+    t.increments('id').primary();
+    t.string('filename').unique().notNullable();
+    t.timestamp('applied_at').defaultTo(db.fn.now());
+  });
+
+  const coreDir = path.resolve(__dirname, '..', '..', '..', 'migrations', 'core');
+  const files = (await fs.promises.readdir(coreDir))
+    .filter((f) => f.endsWith('.js'))
+    .sort();
+
+  for (const f of files) {
+    const mod = require(path.join(coreDir, f));
+    if (typeof mod.up === 'function') {
+      await mod.up(db);
+    }
+    await db('migrations').insert({ filename: f });
+  }
+}
+
+/**
+ * Boot a clean test DB. Returns { db, cleanup, tmpDir }.
+ * Caller must invoke cleanup() in afterAll to release the SQLite file
+ * and the temp directory.
+ */
+async function bootCrmDb() {
+  const tmpDir = await fs.promises.mkdtemp(path.join(os.tmpdir(), 'picpeak-crm-'));
+  process.env.NODE_ENV = 'test';
+  process.env.TEST_DATABASE_PATH = path.join(tmpDir, 'crm.db');
+  process.env.STORAGE_PATH = path.join(tmpDir, 'storage');
+  await fs.promises.mkdir(process.env.STORAGE_PATH, { recursive: true });
+
+  // No jest.resetModules() — every service the test later requires
+  // must share THIS db instance. Two module copies on one SQLite file
+  // each open their own knex pool and the SQLite write lock deadlocks
+  // the second one acquiring a connection. Caller is responsible for
+  // setting TEST_DATABASE_PATH before the first require of db.js
+  // (which knexfile reads at module-init time); bootCrmDb only works
+  // when invoked before any service import.
+  const { db } = require('../../../src/database/db');
+
+  await runCoreMigrations(db);
+
+  return {
+    db,
+    tmpDir,
+    cleanup: async () => {
+      try { await db.destroy(); } catch (_) {}
+      try { await fs.promises.rm(tmpDir, { recursive: true, force: true }); } catch (_) {}
+    },
+  };
+}
+
+/**
+ * Seed the minimal row set that quote/contract/invoice services
+ * dereference on creation: an admin user, an active customer, a
+ * business_profile row, and the app_settings keys the services read.
+ *
+ * Returns the ids the caller will pass into service calls.
+ */
+async function seedMinimal(db) {
+  const passwordHash = await bcrypt.hash('test-pass', 4); // low rounds = fast
+
+  const adminInsert = await db('admin_users').insert({
+    username: 'tester', email: 'tester@example.com',
+    password_hash: passwordHash, must_change_password: false,
+    created_at: new Date(),
+  }).returning('id');
+  const adminId = adminInsert[0]?.id ?? adminInsert[0];
+
+  // business_profile is a singleton; the row is seeded by migration 107
+  // for fresh installs. Defensive: insert if missing.
+  const profile = await db('business_profile').first();
+  if (!profile) {
+    await db('business_profile').insert({
+      legal_name: 'Test Studio',
+      default_currency: 'CHF',
+      default_locale: 'de',
+    });
+  }
+
+  const customerInsert = await db('customer_accounts').insert({
+    email: 'customer@example.com',
+    display_name: 'Test Customer',
+    password_hash: passwordHash,
+    preferred_language: 'de',
+    is_active: 1,
+    created_at: new Date(),
+  }).returning('id');
+  const customerId = customerInsert[0]?.id ?? customerInsert[0];
+
+  return { adminId, customerId };
+}
+
+module.exports = { bootCrmDb, seedMinimal };