# Phase 4.4 Verification Gate — PaymentAllocation Core Engine

**Phase:** 4.4 PaymentAllocation Core Engine  
**Verification Date:** September 4, 2026  
**Status:** PASSED & APPROVED  

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## Verification Criteria & Checklist

| Criteria | Result | Evidence / Implementation Details |
|---|---|---|
| **1. PaymentAllocation Core Engine** | PASS | `app/Domains/Core/Services/PaymentAllocationService.php` fully operational. |
| **2. Customer Payment Allocation** | PASS | `allocateCustomerPayment()` settles Customer Invoices with balance validation. |
| **3. Supplier Payment Allocation** | PASS | `allocateSupplierPayment()` settles Vendor Bills with balance validation. |
| **4. Pessimistic Row Locking** | PASS | `lockForUpdate()` executed on payment and document rows inside `DB::transaction()`. |
| **5. Over-Allocation Prevention** | PASS | Rejects allocations exceeding `unallocated_amount` or `balance_due`. |
| **6. Invalid Document Status Rejection**| PASS | Rejects allocations against `DRAFT`, `CANCELLED`, or `VOIDED` documents. |
| **7. Tenant Security & Isolation** | PASS | Enforces `organization_id` & `business_unit_id` equality (`CrossOrganizationException`). |
| **8. Business-Unit Security** | PASS | Scoped via `BusinessUnitScope` and server-side domain checks. |
| **9. Database Integrity Audit** | PASS | Schema `payment_allocations` verified with proper foreign keys and precision. |
| **10. Concurrency Safety** | PASS | Race conditions prevented via SQL row locking inside database transactions. |
| **11. Zero GL Posting Introduced** | PASS | Accounting boundary preserved; GL postings strictly deferred to Phase 4.7. |
| **12. Code Formatting (Laravel Pint)** | PASS | `vendor/bin/pint --format agent` passed clean (`{"tool":"pint","result":"passed"}`). |
| **13. Full Suite Test Regression** | PASS | 205 / 205 tests passed, 368 assertions, 0 failures, 0 errors, 0 skipped. |

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## Verification Conclusion

Phase 4.4 is **PASSED & APPROVED**.

```text
PHASE 4.4 STATUS: ALREADY IMPLEMENTED / VERIFIED.
HARD STOP. PHASE 4.5 NOT STARTED.
AWAITING HUMAN AUTHORIZATION.
```