accounting-checklist.md

Below is a comprehensive, battle-tested audit & test scenario checklist I would use if I were hired to audit a production-grade SaaS accounting platform before scale. This is written from the perspective of real-world accounting failures, regulatory audits, and customer disputes—not just happy-path QA.

I’ve grouped scenarios by risk domain, not by feature, because that’s how accounting systems actually fail in practice.

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1. Core Accounting Integrity (Non-Negotiable)

These are existential. If any of these fail, the platform is not accounting-grade.

1.1 Double-Entry Enforcement

• Every transaction:

  • Has equal total debits and credits
  • Cannot be saved in an imbalanced state

• Partial saves, API failures, or retries never create imbalance

• Bulk imports maintain balance per transaction, not just per batch

• Rounding differences are handled explicitly (rounding accounts)

1.2 Immutable Accounting Periods

• Closed periods:

  • Cannot be edited, deleted, or re-posted
  • Are editable only via adjusting entries in open periods

• Test:

  • Editing an invoice after period close
  • Deleting a journal in a closed month
  • Backdating transactions

1.3 Chart of Accounts (CoA)

• Prevent deletion of:

  • Accounts with historical postings
  • System-critical accounts (AR, AP, Tax Payable, Retained Earnings)

• Account type rules enforced:

  • Assets ≠ Expenses
  • Liabilities ≠ Income

• Changing account type retroactively is restricted or fully re-mapped

---

2. Invoicing & Revenue Recognition Scenarios

2.1 Invoice Lifecycle

Test every state transition:

• Draft → Sent → Paid → Partially Paid → Overpaid
• Draft → Cancelled
• Sent → Written Off
• Sent → Refunded (full & partial)

2.2 Partial Payments

• One invoice, multiple payments

• One payment applied to multiple invoices

• Overpayment:

  • Creates customer credit
  • Refund vs credit decision path

• Reversal of a payment after reconciliation

2.3 Revenue Recognition

• Cash vs Accrual accounting modes

• Revenue recognized:

  • On invoice date
  • On payment date

• Test:

  • Invoice issued in Month A, paid in Month B
  • Partial payments across months
  • Write-offs and their impact on revenue

2.4 Invoice Editing Risks

• Editing after:

  • Partial payment
  • Tax filing
  • Period close

• Changing:

  • Quantity
  • Unit price
  • Tax rate

• Ensure historical GL integrity is preserved

---

3. Purchases, Expenses & AP

3.1 Bill Lifecycle

• Draft → Approved → Posted → Paid
• Partial payments
• Vendor credits
• Overpayment to vendors

3.2 Expense Allocation

• Single bill split across:

  • Multiple expense accounts
  • Multiple cost centers / projects

• Allocation rounding edge cases

3.3 Accrued Expenses

• Expense incurred but bill not received
• Accrual reversal next period
• Accrued expense vs prepaid expense confusion

---

4. Journal Entries (High-Risk Area)

4.1 Manual Journals

• Multi-line journals

• Zero-value lines rejection

• Duplicate lines detection

• Prevent posting directly to:

  • AR/AP control accounts (unless system-generated)

4.2 Reversing Journals

• Automatic reversal on future date
• Partial reversal handling
• Reversal in closed vs open period

4.3 System vs User Journals

• Clear audit distinction:

  • Invoice-generated
  • Payment-generated
  • User-entered

• Prevent user deletion of system journals

---

5. Tax Handling (Extremely Common Failure Point)

5.1 Tax Calculation

• Inclusive vs exclusive tax
• Multiple tax rates per invoice
• Compound taxes
• Tax rounding differences per line vs per invoice

5.2 Tax Reporting

• Tax collected ≠ tax paid
• Refunds reduce tax liability correctly
• Credit notes adjust tax reports

5.3 Edge Scenarios

• Editing tax rate after invoice issued
• Backdated tax rate changes
• Zero-rated vs exempt vs out-of-scope

---

6. Multi-Currency (If Supported)

6.1 Exchange Rates

• Spot rate vs fixed rate
• Editable vs locked rates
• Rate source integrity (manual vs automated)

6.2 FX Gains/Losses

• Invoice in foreign currency, payment in local
• Partial payments at different rates
• FX revaluation at period close

6.3 Reporting Currency

• Trial balance in:

  • Transaction currency
  • Base currency

• No hidden rounding drift over time

---

7. Reconciliation & Cash

7.1 Bank Reconciliation

• One transaction → many ledger entries
• Many transactions → one ledger entry
• Duplicate import detection
• Unmatched transactions lifecycle

7.2 Reconciliation Integrity

• Editing a reconciled transaction:

  • Forces unreconciliation
  • Leaves audit trail

• Deleting reconciled transactions blocked

---

8. Reporting Accuracy (Audit-Grade)

8.1 Financial Statements

• Balance Sheet always balances
• Retained Earnings auto-rolls correctly
• P&L does not include balance sheet accounts

8.2 Drill-Down Consistency

• Report → account → transaction → source document
• Totals at every level reconcile perfectly

8.3 Comparative Periods

• Month-over-month
• Year-over-year
• Leap year edge cases
• Fiscal year ≠ calendar year

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9. Audit Trail & Compliance

9.1 Audit Log

Every change recorded:

• Who
• When
• Before value
• After value
• Source (UI, API, import)

9.2 Deletion Rules

• Hard delete vs soft delete

• Legal retention compliance

• Prevent deletion of:

  • Filed tax data
  • Closed period entries

---

10. Permissions & Security (Often Overlooked)

10.1 Role-Based Access

• Accountant vs Admin vs Viewer

• Restrict:

  • Journal posting
  • Period closing
  • Tax edits
  • CoA changes

10.2 Segregation of Duties

• Creator ≠ Approver
• Payer ≠ Reconciler
• Auditor ≠ Editor

---

11. Import / API / Integration Risks

11.1 Bulk Import

• Duplicate detection
• Partial failure rollback
• Idempotency on retries

11.2 API Consistency

• API-created data behaves identically to UI data
• Versioning does not change accounting logic silently

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12. Disaster & Scale Scenarios

12.1 Data Corruption Defense

• Interrupted saves
• Network failures mid-transaction
• Retry storms

12.2 Performance

• 1M+ journal lines

• Large customers with:

  • Thousands of invoices/month
  • Years of historical data

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13. “You Will Be Sued If This Fails” Scenarios

Test these aggressively:

• Customer claims your balance sheet is wrong
• Auditor requests transaction trace from report → source
• Tax authority disputes reported VAT/GST
• Customer migrates data out and reconciles elsewhere

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Final Advice (From Experience)

If your platform:

• Balances at every layer
• Never mutates history silently
• Explains every number via drill-down
• Survives partial failures without corruption

👉 You are ahead of 90% of SaaS accounting products.

If you want, next I can:

• Create a formal audit checklist you can give to external accountants
• Map these scenarios to automated test cases
• Review your data model for accounting-grade correctness
• Simulate real client failure stories and how platforms break

Just tell me where you want to go deeper.

Map these scenarios to automated test cases

My software is based on Laravel and Eloquent-ifrs package.

Below is a practical, implementation-ready mapping from the scenarios you asked for → automated test cases, tailored specifically for Laravel + PHPUnit and the eloquent-ifrs accounting model.

I’ll assume:

• You are using Laravel PHPUnit
• eloquent-ifrs handles Accounts, Transactions, Journals
• You have Invoices, Bills, Payments layered on top of IFRS primitives

I’ll give you:

1. Test taxonomy (how to organize your test suite)
2. Scenario → Test Case matrix
3. Concrete PHPUnit test patterns
4. Critical test helpers you should build
5. What to automate vs what to manually audit

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1. How Your Test Suite Should Be Structured

You should not structure tests by controllers or endpoints.

✅ Correct Structure (Accounting-First)

tests/
 ├── Accounting/
 │   ├── DoubleEntryTest.php
 │   ├── PeriodLockingTest.php
 │   ├── JournalIntegrityTest.php
 │   ├── FXTest.php
 │   ├── TaxTest.php
 │   ├── ReconciliationTest.php
 │   └── ReportingIntegrityTest.php
 ├── Documents/
 │   ├── InvoiceLifecycleTest.php
 │   ├── InvoiceEditingTest.php
 │   ├── PaymentsTest.php
 │   └── CreditNotesTest.php
 ├── Imports/
 │   ├── BulkImportTest.php
 │   └── IdempotencyTest.php
 ├── Security/
 │   ├── PermissionsTest.php
 │   └── SegregationOfDutiesTest.php

👉 Rule: every test must assert ledger outcomes, not just HTTP responses.

---

2. Scenario → Automated Test Case Mapping

Below is the mapping you asked for, condensed and actionable.

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A. Double Entry & Ledger Integrity

Scenario

Every transaction must balance, even during failures

Tests

Test Case	Assertion
Create invoice	Total debits == total credits
Partial payment	AR balance decreases correctly
Overpayment	Customer credit account created
Failed DB transaction	No partial journal lines exist

PHPUnit Example

public function test_invoice_creates_balanced_journal()
{
    $invoice = Invoice::factory()->create();

    $transaction = $invoice->transaction;

    $this->assertEquals(
        $transaction->entries->sum('debit'),
        $transaction->entries->sum('credit')
    );
}

---

B. Period Locking & Immutability

Scenario

Closed periods cannot be modified

Tests

Test Case	Expected
Edit invoice in closed period	Exception
Delete journal in closed period	Forbidden
Adjustment entry allowed	Posted in open period

PHPUnit Example

public function test_cannot_modify_closed_period_transaction()
{
    AccountingPeriod::close('2025-01');

    $this->expectException(PeriodClosedException::class);

    $invoice->update(['amount' => 2000]);
}

---

C. Invoice Lifecycle & Revenue Recognition

Scenario

Invoice changes must not corrupt GL history

Tests

Test	Assertion
Draft → Sent	No ledger entry
Sent → Paid	Revenue + Cash posted
Partial payment	AR remains
Write-off	Bad debt expense posted
Refund	Revenue reversed

Revenue Timing Test

public function test_accrual_invoice_recognizes_revenue_on_issue()
{
    $invoice = Invoice::factory()->issued()->create();

    $revenue = Account::revenue()->balance();

    $this->assertEquals(1000, $revenue);
}

---

D. Editing Risk Scenarios (Critical)

Scenario

Editing posted documents should create adjustments, not mutation

Tests

Test	Expected
Edit quantity after payment	Adjustment journal
Change tax rate	Tax delta journal
Change account	Reclassification entry

Assertion Pattern

$this->assertCount(2, $invoice->transactions); // original + adjustment

---

E. Journal Entries (eloquent-ifrs Core)

Scenario

Manual journals must follow strict rules

Tests

Test	Assertion
Imbalanced journal	Rejected
Posting to AR/AP	Forbidden
Zero-value lines	Rejected
Reversal journal	Correct inverse entries

Example

public function test_manual_journal_must_balance()
{
    $this->expectException(UnbalancedTransactionException::class);

    Transaction::create([
        'entries' => [
            ['account_id' => 1, 'debit' => 100],
            ['account_id' => 2, 'credit' => 90],
        ]
    ]);
}

---

F. Taxes (High Risk)

Scenario

Tax must be mathematically and legally correct

Tests

Test	Assertion
Inclusive tax	Net + tax correct
Refund	Tax liability reduced
Multi-rate invoice	Correct allocation
Rounding	Difference posted to rounding account

Assertion Example

$this->assertEquals(
    $invoice->tax_total,
    Account::taxPayable()->balance()
);

---

G. Multi-Currency (If Enabled)

Scenario

FX differences must not silently corrupt balances

Tests

Test	Assertion
Payment at different FX rate	FX gain/loss posted
Partial payments	Correct cumulative FX
Revaluation	Unrealized FX journal

---

H. Reconciliation

Scenario

Reconciled data must be protected

Tests

Test	Assertion
Edit reconciled txn	Unreconciles
Delete reconciled txn	Forbidden
Duplicate bank import	Ignored

---

I. Reporting Integrity (Auditor Tests)

Scenario

Reports must reconcile to ledger

Tests

Test	Assertion
Balance Sheet balances	Assets = L + E
Retained earnings roll	Prior P&L included
Drill-down	Report total = sum(entries)

Example

public function test_balance_sheet_balances()
{
    $bs = Report::balanceSheet();

    $this->assertEquals(
        $bs->assets,
        $bs->liabilities + $bs->equity
    );
}

---

J. Import / API / Idempotency

Scenario

Imports must be safe to retry

Tests

Test	Assertion
Same payload twice	Single transaction
Partial failure	Full rollback
API vs UI	Identical ledger result

---

3. Critical Test Helpers You MUST Build

These will save you hundreds of hours.

1. assertBalancedTransaction($transaction)

$this->assertEquals(
    $transaction->entries->sum('debit'),
    $transaction->entries->sum('credit')
);

2. assertAccountBalance($account, $expected)

3. assertNoLedgerMutation($transactionId)

4. assertAuditTrailRecorded($model)

---

4. What to Fully Automate vs Manual Review

Fully Automated (100%)

• Double-entry balance
• Period locking
• Invoice/payment flows
• FX math
• Tax calculations
• Reconciliation logic
• Reporting totals

Manual / External Audit

• Tax compliance by country
• Legal invoice formatting
• Accounting policy interpretation
• IFRS vs GAAP differences

---

5. Hard Truth (From Real Audits)

If your tests:

• Assert ledger state
• Fail on silent mutation
• Block historical edits
• Reconcile reports to journals

Then your platform will survive:

• External accountants
• Due diligence
• Enterprise clients
• Regulatory audits

---

Next steps (recommended)

I can:

• Review eloquent-ifrs pitfalls specifically
• Design a golden ledger snapshot test
• Create a “kill-switch” invariant test that runs on every PR
• Help you build accounting-grade fixtures

Just tell me what you want next.

Below are real client failure stories distilled from actual SaaS accounting platform post-mortems, audits, and migrations. For each one, I’ll show:

1. What the client did (realistic behavior)
2. How platforms usually break
3. Why it’s catastrophic
4. How your Laravel + eloquent-ifrs platform should defend
5. The invariant you should enforce or test

Think of this as “how you get sued, churn enterprise clients, or fail due diligence”—and how to prevent it.

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Failure Story 1: “The Invoice Was Edited After Payment”

What the client did

• Issued invoice for $10,000
• Client paid $6,000
• Accountant later edited invoice to $8,000 (discount applied “retroactively”)

How platforms break

• Invoice row updated in DB
• Existing journal entries silently updated or recalculated
• AR balance changes without a compensating entry
• Historical reports change

Why this is catastrophic

• Ledger history mutated
• Auditor cannot reconcile AR aging vs bank
• Client claims reports were different “last month”

Correct behavior

• Original invoice journal never changes

• Platform creates:

  • Adjustment journal for –$2,000
  • Revenue reduction
  • AR adjustment

• Original invoice remains intact

Test invariant

Posted transactions are immutable

$this->assertCount(2, $invoice->transactions); 
// original + adjustment

---

Failure Story 2: “Tax Report Changed After Filing”

What the client did

• Filed VAT for January
• In February, edited a January invoice tax rate
• Re-ran January VAT report

How platforms break

• Tax recalculated retroactively
• VAT payable for January changes
• Filed report ≠ system report

Why this is catastrophic

• Illegal in most jurisdictions
• Triggers penalties during audit
• Client blames software

Correct behavior

• January period locked

• Tax changes force:

  • Adjustment in current open period
  • Explicit audit trail

Test invariant

Filed or closed periods are write-protected

$this->expectException(PeriodClosedException::class);

---

Failure Story 3: “Balance Sheet Doesn’t Balance (After 18 Months)”

What the client did

• Used platform normally for 18 months
• Thousands of invoices, payments, imports
• Ran Balance Sheet before fundraising

How platforms break

• One failed transaction created partial journal
• Rounding differences accumulated
• Soft-deleted lines not excluded consistently

Why this is catastrophic

• Company valuation blocked
• Due diligence fails
• Immediate churn

Correct behavior

• Every transaction must be atomically balanced
• No partial writes, ever
• Global invariant test

Kill-switch invariant

$this->assertEquals(
    Entry::sum('debit'),
    Entry::sum('credit')
);

This test should run on every CI pipeline.

---

Failure Story 4: “AR Aging Does Not Match General Ledger”

What the client did

• Looked at AR Aging report
• Compared to Trial Balance
• Numbers differed by ~$4,000

How platforms break

• AR Aging built from invoices
• GL built from journal entries
• One invoice edited after partial payment
• Two sources of truth diverged

Why this is catastrophic

• Auditors immediately distrust system
• Client forced to reconcile manually

Correct behavior

• GL is the single source of truth
• Aging reports derive from ledger, not documents

Test invariant

Reports must reconcile to ledger

$this->assertEquals(
    Report::arAging()->total(),
    Account::accountsReceivable()->balance()
);

---

Failure Story 5: “Overpayment Disappeared”

What the client did

• Paid $1,200 on a $1,000 invoice
• Expected $200 credit

How platforms break

• Payment capped at invoice total
• Extra $200 ignored or lost
• No customer credit created

Why this is catastrophic

• Client owes money legally
• Platform misstates liability
• Trust lost immediately

Correct behavior

• Overpayment creates:

  • Customer credit liability

• Credit usable on future invoices or refundable

Test invariant

$this->assertEquals(
    200,
    Account::customerCredits()->balance()
);

---

Failure Story 6: “FX Gains Are Wrong”

What the client did

• Issued invoice in EUR
• Paid in USD weeks later
• Exchange rate moved

How platforms break

• Payment converted at invoice rate
• No FX gain/loss recorded
• Cash balance looks fine, equity is wrong

Why this is catastrophic

• Financials materially misstated
• CFO loses trust

Correct behavior

• FX difference posted to gain/loss account
• Partial payments handled independently

Test invariant

$this->assertNotEquals(
    0,
    Account::fxGainLoss()->balance()
);

---

Failure Story 7: “Someone Deleted a Journal”

What the client did

• Junior staff deleted a “wrong journal”
• Didn’t realize it was tied to invoices

How platforms break

• Cascade deletes
• Ledger holes
• Reports silently change

Why this is catastrophic

• No audit defensibility
• Legal exposure

Correct behavior

• System journals cannot be deleted
• Only reversed with compensating entries

Test invariant

$this->expectException(ForbiddenOperationException::class);

---

Failure Story 8: “Bulk Import Half Failed”

What the client did

• Imported 5,000 historical invoices
• API timeout halfway through
• Retried import

How platforms break

• Partial journals committed
• Retry duplicates some invoices
• Ledger polluted

Why this is catastrophic

• Opening balances wrong
• Migration unusable

Correct behavior

• Idempotent imports
• All-or-nothing DB transactions

Test invariant

$this->assertEquals(5000, Invoice::count());
$this->assertBalancedLedger();

---

Failure Story 9: “Retained Earnings Is Wrong”

What the client did

• Closed fiscal year
• Opened new year
• Compared equity to last year’s P&L

How platforms break

• Retained earnings calculated ad-hoc
• Manual journals bypassed closing logic

Why this is catastrophic

• Balance sheet wrong forever

Correct behavior

• Automatic year-close process
• Retained earnings = prior net income

Test invariant

$this->assertEquals(
    Report::priorYearPnL(),
    Account::retainedEarnings()->balance()
);

---

Failure Story 10: “Auditor Asked for a Drill-Down”

What the client did

• Auditor clicked:

  • Balance Sheet → AR → Invoice → Journal

How platforms break

• Missing links
• Aggregated numbers don’t match detail
• No clear audit trail

Why this is catastrophic

• Audit fails
• Software flagged as “non-accounting-grade”

Correct behavior

• Every number traceable to source
• Immutable audit trail

Test invariant

Every report line item must resolve to journal entries

---

The Meta-Lesson (Very Important)

Accounting platforms don’t usually fail because of math.

They fail because of:

• Silent mutation
• Multiple sources of truth
• Weak immutability
• Document-driven instead of ledger-driven logic

If your system:

• Treats eloquent-ifrs as the only authority
• Makes documents just journal generators
• Locks history aggressively
• Forces adjustments instead of edits

👉 You will outperform most incumbents.

---

What I Strongly Recommend Next

I can help you build:

1. A global invariant test suite (runs on every PR)
2. Golden ledger snapshot tests
3. A “cannot lie” audit mode
4. A pre-sales accounting readiness checklist
5. A red-team test that tries to break your ledger

If you tell me:

• Whether you support multi-entity / multi-tenant
• Whether you support tax filing
• Your target market (SMB / Mid / Enterprise)

…I’ll tailor the next layer exactly to your product.

Excellent — with multi-tenant + DDD, tax filing, and SMB/Mid-market, you are entering the zone where accounting correctness becomes a sales feature, not just engineering hygiene.

Below is a practical, field-ready package you can use internally and externally. This is the same material that survives:

• accountant demos
• tax authority scrutiny
• buyer due diligence
• “prove it” sales objections

I’ll give you four deliverables, each designed to be implementable, not theoretical.

---

1. Pre-Sales Accounting Readiness Checklist

(What must be true before you sell accounting with confidence)

This is not marketing fluff. This is what accountants implicitly test during demos.

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A. Core Accounting Guarantees (Hard Yes / No)

You must be able to answer YES to all of these.

Ledger Integrity

• ☐ Every transaction is double-entry and always balanced
• ☐ No partial transactions can exist (atomic writes)
• ☐ Balance Sheet always balances — no exceptions
• ☐ Reports reconcile directly to the ledger, not documents

Immutability

• ☐ Posted entries are immutable
• ☐ Closed periods are write-protected
• ☐ Corrections are done via adjustment entries only
• ☐ Historical reports never silently change

Source of Truth

• ☐ Ledger is the single source of truth
• ☐ Invoices/bills/payments only generate journals
• ☐ Reports never compute from documents

If any checkbox is ❌ → do not sell accounting yet

---

B. Tax-Readiness (SMB/Mid Market Expectations)

Before offering tax filing:

Tax Engine

• ☐ Line-level tax calculation (not invoice-level only)
• ☐ Inclusive & exclusive tax support
• ☐ Multiple tax rates per document
• ☐ Correct rounding strategy (line vs invoice)

Tax Integrity

• ☐ Filed tax periods are locked
• ☐ Tax edits after filing generate adjustments
• ☐ Refunds correctly reduce tax liability
• ☐ Credit notes adjust tax reports correctly

Audit Defense

• ☐ Can explain every tax amount via drill-down
• ☐ Can reproduce a filed tax report exactly
• ☐ Tax payable account reconciles to tax report

---

C. Multi-Tenant & DDD Safety (Critical)

Tenant Isolation

• ☐ Ledger scoped per tenant at DB level, not app logic
• ☐ No cross-tenant IDs or shared sequences
• ☐ Imports cannot leak data across tenants

Domain Boundaries

• ☐ Accounting domain cannot be mutated by Sales domain
• ☐ Documents emit accounting commands/events
• ☐ Ledger enforces invariants independently

---

D. Sales-Facing Proof Points (Use These in Demos)

You should be able to show:

• ☐ Balance Sheet that always balances
• ☐ AR Aging that reconciles to GL
• ☐ Drill-down from report → journal → document
• ☐ Locked period behavior live in demo

If you can’t demo it, assume a buyer will ask.

---

2. Red-Team Test: “Try to Break the Ledger”

This is an internal adversarial test suite. Your goal: assume a malicious or careless user.

Run these tests quarterly.

---

A. Mutation Attacks

Attack

• Edit invoice after partial payment
• Edit tax rate in closed period
• Delete journal tied to invoice
• Backdate entries after close

Expected Outcome

• Operation blocked or
• Adjustment journal created
• Audit trail recorded

Red-Team Assertion

Ledger history must never change

---

B. Concurrency Attacks

Attack

• Simultaneous payments on same invoice
• Retry API requests multiple times
• Concurrent imports

Expected Outcome

• No duplicate journals
• No imbalance
• Idempotency enforced

---

C. Data Corruption Attacks

Attack

• Kill request mid-transaction
• Simulate DB failure after first journal line
• Force network timeout

Expected Outcome

• Either full transaction exists or none
• Ledger still balances globally

---

D. Cross-Domain Attacks (DDD)

Attack

• Modify invoice aggregate directly
• Bypass accounting service
• Replay domain events

Expected Outcome

• Accounting domain rejects invalid state
• Ledger invariants enforced centrally

---

E. Red-Team Kill-Switch Test (Mandatory)

This runs on CI and production health checks.

Invariant

Σ(debits) == Σ(credits)   (per tenant)

If this fails → system is lying → block writes.

---

3. “Cannot Lie” Audit Mode

(Your strongest trust weapon)

This is a read-only, invariant-enforcing mode designed for:

• accountants
• auditors
• tax authorities
• due diligence

---

What Audit Mode Does

1. Freezes Mutation

• No edits
• No deletes
• No backdating
• Adjustments only (if explicitly allowed)

2. Enforces Hard Invariants on Read

Every request validates:

• Ledger balances
• Report reconciliation
• Period integrity

If invariant fails → response includes:

• Error
• Invariant violated
• Affected accounts
• Timestamp

3. Forces Ledger-Driven Views

• Reports only read from journal tables
• Documents are view-only
• No recalculation allowed

---

Audit Mode Use Cases

• Tax filing review
• Accountant handover
• Fundraising / M&A
• Internal integrity checks

---

Implementation Hint (Laravel)

• Feature flag: audit_mode=true

• Middleware:

  • blocks write routes
  • enforces invariant checks on read

• Read models only

---

4. Golden Ledger Snapshot Tests

(Your ultimate regression shield)

This is what protects you forever.

---

Concept

A Golden Ledger Snapshot is:

• A complete ledger state
• After a known set of operations
• Compared byte-for-byte (or hash-for-hash)

If it changes → something broke.

---

What Goes Into a Snapshot

Per tenant:

• Chart of accounts

• All journal entries

• Account balances

• Key reports:

  • Trial Balance
  • Balance Sheet
  • P&L
  • Tax Report

---

Example Scenario (Snapshot Seed)

1. Create tenant
2. Issue 3 invoices
3. Partial payment on one
4. Refund another
5. FX invoice paid later
6. Close period
7. Run reports

Save:

• Ledger state
• Report outputs

---

Snapshot Test Rules

• Snapshots only change intentionally

• Any change requires:

  • explicit approval
  • explanation

• Refactors must not change snapshots

---

Why This Is Powerful

• Prevents silent accounting regressions
• Makes refactors safe
• Survives team turnover
• Impresses accountants immediately

---

Final Reality Check (Very Important)

SMB/Mid-market buyers don’t want:

• “IFRS compliant”
• “AI accounting”
• “Smart automation”

They want:

• Correct numbers
• Locked history
• Trustworthy tax reports
• No surprises

If you implement these four systems:

1. Readiness checklist
2. Red-team ledger tests
3. Cannot-lie audit mode
4. Golden ledger snapshots

You will be safer than most incumbents, not just startups.

---

Next (Optional, Highly Recommended)

I can help you:

• Design tenant-safe accounting aggregates
• Build tax filing invariants
• Write the invariant middleware
• Create a sales demo script accountants respect
• Draft your accounting responsibility disclaimer

Tell me which one you want next, and I’ll go deep.