diff --git a/.planning/phases/24-aws-route-53-dns-sync-track-changes-crud-operations-full-aud/24-03-SUMMARY.md b/.planning/phases/24-aws-route-53-dns-sync-track-changes-crud-operations-full-aud/24-03-SUMMARY.md
new file mode 100644
index 0000000..70c159a
--- /dev/null
+++ b/.planning/phases/24-aws-route-53-dns-sync-track-changes-crud-operations-full-aud/24-03-SUMMARY.md
@@ -0,0 +1,131 @@
+---
+phase: 24-aws-route-53-dns-sync-track-changes-crud-operations-full-aud
+plan: 03
+subsystem: route53-crud-write-persistence
+tags: [route53, dns, crud, audit, validation, security]
+dependency-graph:
+  requires: ["24-01"]
+  provides:
+    - "lib/services/route53-record-validation.ts (WRITABLE_RECORD_TYPES, validateRecordWrite, sanitizeAwsError)"
+    - "lib/services/route53-write-persistence.ts (createPendingAuditLog, markAuditCommitted, markAuditFailed, insertPulseCrudHistory, upsertMirrorRecord, softDeleteMirrorRecord, loadMirrorRecord)"
+  affects:
+    - "plan 24-05 (CRUD routes will import both modules directly)"
+tech-stack:
+  added: []
+  patterns:
+    - "pending -> committed/failed audit lifecycle (mirrors lib/services/analyzer/asset-audit/persistence.ts)"
+    - "closed allowlist validation (mirrors app/api/analyzer/itglue/.../apply/route.ts credential-field blocklist pattern, inverted to an allowlist)"
+key-files:
+  created:
+    - lib/services/route53-record-validation.ts
+    - lib/services/route53-record-validation.test.ts
+    - lib/services/route53-write-persistence.ts
+    - lib/services/route53-write-persistence.test.ts
+  modified:
+    - .planning/phases/24-aws-route-53-dns-sync-track-changes-crud-operations-full-aud/deferred-items.md
+decisions:
+  - "ValidateRecordWriteInput fields are optional (name?, type?) rather than required, since the whole point of the validator is to accept untrusted/arbitrary request-body shapes at runtime — TypeScript's structural typing otherwise blocked constructing test payloads that omit a field to prove the runtime check fires"
+metrics:
+  duration_minutes: 25
+  tasks_completed: 2
+  files_created: 4
+  files_modified: 1
+  test_assertions_added: 32
+  completed: 2026-08-06
+---
+
+# Phase 24 Plan 03: Record Validation and Write-Persistence Summary
+
+Server-side D-01 record-type allowlist validator + AWS error sanitizer, and the pending
+-> committed/failed audit lifecycle with pulse_crud history persistence that the plan
+24-05 CRUD routes will depend on.
+
+## What Was Built
+
+**`lib/services/route53-record-validation.ts`**
+- `WRITABLE_RECORD_TYPES`: frozen array of exactly `['A', 'AAAA', 'CNAME', 'MX', 'TXT', 'SRV']` —
+  a closed allowlist. `NS`/`SOA` appear nowhere in this array; they only appear inside the
+  rejection branch's `ZONE_DELEGATION_TYPES` set and its explicit reason message.
+- `validateRecordWrite(input)`: validates `name` (trim/lowercase/trailing-dot normalization),
+  `type` (case-insensitive uppercase match against the allowlist, explicit delegation-aware
+  rejection reason for NS/SOA, generic rejection for any other unlisted type such as CAA/DS),
+  `ttl` (integer 0..2147483647, default 300), and `resourceRecords` (non-empty array, each
+  entry a non-empty string value, capped at 100 entries — T-24-12 DoS guard). No AWS SDK or
+  Postgres import — confirmed by `grep -c "@aws-sdk\|postgres-client"` returning 0.
+- `sanitizeAwsError(err)`: redacts `AKIA`-prefixed access key ids, `arn:aws:*` substrings, and
+  12-digit AWS account ids, then truncates to 500 characters. Never throws, even on
+  non-Error input.
+- 23 test assertions cover every `<behavior>` bullet including case-insensitivity (`NS`/`ns`),
+  the closed-allowlist rejection of an unlisted type (`CAA`, `DS`), TTL boundary values, and
+  the sanitizer stripping both an example AWS key id and ARN from a single error message.
+
+**`lib/services/route53-write-persistence.ts`**
+- `createPendingAuditLog` / `markAuditCommitted` / `markAuditFailed`: the three-function
+  pending -> committed/failed shape mirrored from
+  `lib/services/analyzer/asset-audit/persistence.ts`. `createPendingAuditLog` must be awaited
+  before any AWS `ChangeResourceRecordSetsCommand` is constructed by the (future) CRUD routes.
+  `markAuditFailed` always routes the error through `sanitizeAwsError` — never a raw error
+  object or `JSON.stringify(err)`.
+- `insertPulseCrudHistory`: writes a `source='pulse_crud'` row to `route53_record_history`.
+  Documented directly above the function that it must only be called after
+  `markAuditCommitted` — a failed AWS attempt gets an audit row but no history row.
+- `upsertMirrorRecord` / `softDeleteMirrorRecord`: best-effort refresh/soft-delete of the
+  `route53_records` mirror after a committed write. Wrapped in try/catch, logged with a
+  `[ROUTE53-WRITE]` prefix via `sanitizeAwsError`, never thrown — the AWS write already
+  succeeded and the next incremental sync reconciles regardless. Confirmed
+  `grep -c 'DELETE FROM route53_records'` returns 0 — soft-delete only (D-08).
+- `loadMirrorRecord`: manual snake_case -> camelCase transform (no ORM, per CLAUDE.md) of the
+  current mirror row, supplying `before_value` and the exact TTL/value set a Route 53 DELETE
+  needs to match.
+- 9 test assertions against a mocked `postgresClient` (same `vi.mock` style as
+  `pax8-sync-service.test.ts`) verify: the pending INSERT contains `'pending'`, the committed/
+  failed UPDATEs contain their respective status literals, `markAuditFailed`'s bound
+  parameters never contain a raw AWS key id, `insertPulseCrudHistory` binds the literal
+  `'pulse_crud'`, `softDeleteMirrorRecord` never issues `DELETE FROM`, both mirror helpers
+  resolve (never throw) even when the underlying query rejects, and `loadMirrorRecord`
+  correctly transforms a found row / returns `null` when absent.
+
+## Verification
+
+- `npx vitest run lib/services/route53-record-validation.test.ts lib/services/route53-write-persistence.test.ts` — 32/32 passed
+- `npx tsc --noEmit --pretty` — exits 0
+- `npm test` (full suite) — 499/501 passed; 2 pre-existing failures in
+  `lib/services/analyzer/itglue-search.test.ts`, unrelated to this plan (see Deferred Issues)
+- `grep -c "'NS'\|'SOA'" lib/services/route53-record-validation.ts` — 1 (only inside the
+  rejection Set/reason, never inside `WRITABLE_RECORD_TYPES`)
+- `grep -c "@aws-sdk\|postgres-client" lib/services/route53-record-validation.ts` — 0
+- `grep -c 'DELETE FROM route53_records' lib/services/route53-write-persistence.ts` — 0
+- `grep -q 'sanitizeAwsError' lib/services/route53-write-persistence.ts` — found
+- `grep -c "'pulse_crud'" lib/services/route53-write-persistence.ts` — 2
+
+## Deviations from Plan
+
+None — plan executed exactly as written, aside from one non-substantive typing adjustment:
+
+**1. [Rule 3 - blocking issue] `ValidateRecordWriteInput` fields made optional**
+- **Found during:** Task 1, `npx tsc --noEmit --pretty`
+- **Issue:** The plan's signature `validateRecordWrite(input: { name: unknown; type: unknown; ... })`
+  requires the `name`/`type` properties to be present (even though typed `unknown`).
+  A behavior test intentionally omits `name` to prove the runtime "missing name" rejection
+  fires — TypeScript's structural typing blocked constructing that test payload.
+- **Fix:** Made `name?: unknown` and `type?: unknown` optional in the internal
+  `ValidateRecordWriteInput` interface. Runtime behavior is unchanged (the function still
+  checks `typeof input.name !== 'string'`, which already covers `undefined`).
+- **Files modified:** `lib/services/route53-record-validation.ts`
+- **Commit:** 4be4a19
+
+## Deferred Issues
+
+None specific to this plan's own code. Two pre-existing, unrelated `npm test` failures in
+`lib/services/analyzer/itglue-search.test.ts` were re-observed during full-suite verification
+and logged (not fixed, out of scope) in `deferred-items.md` under both the original Plan 24-01
+entry and a new Plan 24-03 entry.
+
+## Self-Check: PASSED
+
+- FOUND: lib/services/route53-record-validation.ts
+- FOUND: lib/services/route53-record-validation.test.ts
+- FOUND: lib/services/route53-write-persistence.ts
+- FOUND: lib/services/route53-write-persistence.test.ts
+- FOUND commit: 4be4a19
+- FOUND commit: 8b5e926
diff --git a/.planning/phases/24-aws-route-53-dns-sync-track-changes-crud-operations-full-aud/deferred-items.md b/.planning/phases/24-aws-route-53-dns-sync-track-changes-crud-operations-full-aud/deferred-items.md
index 364f6c7..4c5f52c 100644
--- a/.planning/phases/24-aws-route-53-dns-sync-track-changes-crud-operations-full-aud/deferred-items.md
+++ b/.planning/phases/24-aws-route-53-dns-sync-track-changes-crud-operations-full-aud/deferred-items.md
@@ -14,3 +14,11 @@ changes).
   confirms zero changes to either path from Task 1 or Task 2). Unrelated to
   the Route 53 factory/schema work in this plan — not fixed, logged here for
   visibility.
+
+## Plan 24-03
+
+- Same 2 pre-existing `lib/services/analyzer/itglue-search.test.ts` failures
+  re-surfaced by `npm test` (full suite) while verifying Task 2's
+  `route53-write-persistence.ts`. Neither `itglue-search.ts` nor its test
+  file were touched by this plan. Out of scope per the scope boundary rule —
+  not fixed.
diff --git a/lib/services/route53-record-validation.test.ts b/lib/services/route53-record-validation.test.ts
new file mode 100644
index 0000000..1008bfb
--- /dev/null
+++ b/lib/services/route53-record-validation.test.ts
@@ -0,0 +1,163 @@
+/**
+ * lib/services/route53-record-validation.ts unit tests — D-01 allowlist
+ * enforcement and AWS error sanitization (T-24-03). Pure logic, no AWS SDK
+ * or Postgres dependency to mock.
+ */
+
+import { describe, it, expect } from 'vitest';
+import {
+  WRITABLE_RECORD_TYPES,
+  validateRecordWrite,
+  sanitizeAwsError,
+} from './route53-record-validation';
+
+describe('WRITABLE_RECORD_TYPES', () => {
+  it('is exactly the six D-01 writable types, never NS or SOA', () => {
+    expect([...WRITABLE_RECORD_TYPES].sort()).toEqual(
+      ['A', 'AAAA', 'CNAME', 'MX', 'SRV', 'TXT'].sort()
+    );
+    expect(WRITABLE_RECORD_TYPES).not.toContain('NS');
+    expect(WRITABLE_RECORD_TYPES).not.toContain('SOA');
+  });
+});
+
+describe('validateRecordWrite', () => {
+  const basePayload = {
+    name: 'www.example.com',
+    resourceRecords: [{ value: '1.2.3.4' }],
+  };
+
+  it('rejects NS with a reason naming it as a zone-delegation record', () => {
+    const result = validateRecordWrite({ ...basePayload, type: 'NS' });
+    expect(result.ok).toBe(false);
+    if (!result.ok) {
+      expect(result.status).toBe(400);
+      expect(result.reason).toMatch(/NS/);
+      expect(result.reason).toMatch(/delegation/i);
+    }
+  });
+
+  it('rejects SOA', () => {
+    const result = validateRecordWrite({ ...basePayload, type: 'SOA' });
+    expect(result.ok).toBe(false);
+    if (!result.ok) expect(result.status).toBe(400);
+  });
+
+  it('rejects lowercase "ns" case-insensitively', () => {
+    const result = validateRecordWrite({ ...basePayload, type: 'ns' });
+    expect(result.ok).toBe(false);
+    if (!result.ok) {
+      expect(result.status).toBe(400);
+      expect(result.reason).toMatch(/delegation/i);
+    }
+  });
+
+  it.each(['A', 'AAAA', 'CNAME', 'MX', 'TXT', 'SRV'])(
+    'accepts well-formed %s payload',
+    (type) => {
+      const result = validateRecordWrite({ ...basePayload, type });
+      expect(result.ok).toBe(true);
+      if (result.ok) {
+        expect(result.value.type).toBe(type);
+        expect(result.value.name).toBe('www.example.com.');
+        expect(result.value.ttl).toBe(300);
+      }
+    }
+  );
+
+  it('rejects an unknown type such as CAA (closed allowlist, not a blocklist)', () => {
+    const result = validateRecordWrite({ ...basePayload, type: 'CAA' });
+    expect(result.ok).toBe(false);
+    if (!result.ok) expect(result.status).toBe(400);
+  });
+
+  it('rejects an unknown type such as DS', () => {
+    const result = validateRecordWrite({ ...basePayload, type: 'DS' });
+    expect(result.ok).toBe(false);
+    if (!result.ok) expect(result.status).toBe(400);
+  });
+
+  it('rejects a missing name', () => {
+    const result = validateRecordWrite({ type: 'A', resourceRecords: [{ value: '1.2.3.4' }] });
+    expect(result.ok).toBe(false);
+    if (!result.ok) expect(result.status).toBe(400);
+  });
+
+  it('rejects an empty-string name', () => {
+    const result = validateRecordWrite({ ...basePayload, name: '   ', type: 'A' });
+    expect(result.ok).toBe(false);
+    if (!result.ok) expect(result.status).toBe(400);
+  });
+
+  it('rejects a non-integer ttl', () => {
+    const result = validateRecordWrite({ ...basePayload, type: 'A', ttl: 3.5 });
+    expect(result.ok).toBe(false);
+    if (!result.ok) expect(result.status).toBe(400);
+  });
+
+  it('rejects a ttl outside 0..2147483647', () => {
+    const tooHigh = validateRecordWrite({ ...basePayload, type: 'A', ttl: 2147483648 });
+    expect(tooHigh.ok).toBe(false);
+    const tooLow = validateRecordWrite({ ...basePayload, type: 'A', ttl: -1 });
+    expect(tooLow.ok).toBe(false);
+  });
+
+  it('accepts ttl of exactly 0 and exactly 2147483647', () => {
+    const min = validateRecordWrite({ ...basePayload, type: 'A', ttl: 0 });
+    expect(min.ok).toBe(true);
+    const max = validateRecordWrite({ ...basePayload, type: 'A', ttl: 2147483647 });
+    expect(max.ok).toBe(true);
+  });
+
+  it('rejects an empty resourceRecords array (Route 53 rejects an empty value set)', () => {
+    const result = validateRecordWrite({ name: 'www.example.com', type: 'A', resourceRecords: [] });
+    expect(result.ok).toBe(false);
+    if (!result.ok) expect(result.status).toBe(400);
+  });
+
+  it('rejects a resourceRecords entry with an empty-string value', () => {
+    const result = validateRecordWrite({
+      name: 'www.example.com',
+      type: 'A',
+      resourceRecords: [{ value: '' }],
+    });
+    expect(result.ok).toBe(false);
+    if (!result.ok) expect(result.status).toBe(400);
+  });
+
+  it('caps resourceRecords at 100 entries', () => {
+    const tooMany = Array.from({ length: 101 }, (_, i) => ({ value: `10.0.0.${i % 256}` }));
+    const result = validateRecordWrite({ name: 'www.example.com', type: 'A', resourceRecords: tooMany });
+    expect(result.ok).toBe(false);
+    if (!result.ok) expect(result.status).toBe(400);
+  });
+});
+
+describe('sanitizeAwsError', () => {
+  it('strips AWS access key ids, ARNs, and account ids, then truncates to 500 chars', () => {
+    const err = new Error(
+      'AccessDenied for AKIAIOSFODNN7EXAMPLE on arn:aws:route53:::hostedzone/Z123 account 123456789012'
+    );
+    const sanitized = sanitizeAwsError(err);
+    expect(sanitized).not.toContain('AKIAIOSFODNN7EXAMPLE');
+    expect(sanitized).not.toContain('arn:aws:route53:::hostedzone/Z123');
+    expect(sanitized).not.toContain('123456789012');
+    expect(sanitized.length).toBeLessThanOrEqual(504);
+  });
+
+  it('truncates messages longer than 500 characters', () => {
+    const longMessage = 'x'.repeat(1000);
+    const sanitized = sanitizeAwsError(new Error(longMessage));
+    expect(sanitized.length).toBeLessThanOrEqual(504);
+    expect(sanitized.endsWith('...')).toBe(true);
+  });
+
+  it('never throws on a non-Error input and returns a string', () => {
+    expect(() => sanitizeAwsError('a plain string error')).not.toThrow();
+    expect(typeof sanitizeAwsError('a plain string error')).toBe('string');
+    expect(() => sanitizeAwsError(undefined)).not.toThrow();
+    expect(typeof sanitizeAwsError(undefined)).toBe('string');
+    expect(() => sanitizeAwsError({ weird: 'object' })).not.toThrow();
+    expect(typeof sanitizeAwsError(null)).toBe('string');
+  });
+});
diff --git a/lib/services/route53-record-validation.ts b/lib/services/route53-record-validation.ts
new file mode 100644
index 0000000..30fb74e
--- /dev/null
+++ b/lib/services/route53-record-validation.ts
@@ -0,0 +1,171 @@
+/**
+ * AWS Route 53 DNS sync — server-side write validation + AWS error sanitizer.
+ *
+ * D-01: A closed allowlist of writable record types. NS and SOA are
+ * zone-delegation records and must never be writable from Pulse — this check
+ * runs in library code the CRUD routes call BEFORE any AWS command is
+ * constructed, mirroring the credential-field blocklist pattern in
+ * app/api/analyzer/itglue/applications/[id]/apply/route.ts (belt over the
+ * UI's braces: never rely on the UI simply not offering the option).
+ *
+ * T-24-03: `sanitizeAwsError` is the only permitted source of a persisted or
+ * client-returned AWS error string — it strips access key ids, ARNs, and AWS
+ * account ids before the message is written to `route53_audit_log.error_message`
+ * or returned in an API response body.
+ *
+ * No AWS SDK or Postgres dependency here by design — this module is plain,
+ * synchronous, unit-testable validation logic.
+ */
+
+import type { Route53RecordValue, Route53WritableType } from '@/lib/types/route53';
+
+/**
+ * D-01: closed allowlist. NS and SOA are deliberately absent — an
+ * unrecognized type is rejected, never passed through.
+ */
+export const WRITABLE_RECORD_TYPES: readonly Route53WritableType[] = Object.freeze([
+  'A',
+  'AAAA',
+  'CNAME',
+  'MX',
+  'TXT',
+  'SRV',
+]);
+
+const MIN_TTL = 0;
+const MAX_TTL = 2147483647;
+const MAX_RESOURCE_RECORDS = 100;
+const ZONE_DELEGATION_TYPES = new Set(['NS', 'SOA']);
+
+export interface ValidatedRecordWrite {
+  name: string;
+  type: Route53WritableType;
+  ttl: number;
+  resourceRecords: Route53RecordValue[];
+}
+
+export type ValidateRecordWriteResult =
+  | { ok: true; value: ValidatedRecordWrite }
+  | { ok: false; status: 400; reason: string };
+
+interface ValidateRecordWriteInput {
+  name?: unknown;
+  type?: unknown;
+  ttl?: unknown;
+  resourceRecords?: unknown;
+}
+
+function fail(reason: string): ValidateRecordWriteResult {
+  return { ok: false, status: 400, reason };
+}
+
+/**
+ * Validate a record write payload against D-01's closed allowlist and basic
+ * shape rules. Does not construct any AWS command and has no DB dependency —
+ * callers invoke this first and only proceed to build a
+ * ChangeResourceRecordSetsCommand when `ok` is true.
+ */
+export function validateRecordWrite(input: ValidateRecordWriteInput): ValidateRecordWriteResult {
+  // 1. name: non-empty string after trimming, normalized to Route 53's
+  // canonical lowercase + trailing-dot form.
+  if (typeof input.name !== 'string' || input.name.trim().length === 0) {
+    return fail('Record name is required and must be a non-empty string');
+  }
+  let name = input.name.trim().toLowerCase();
+  if (!name.endsWith('.')) {
+    name = `${name}.`;
+  }
+
+  // 2. type: string, uppercased, must be a member of the closed allowlist.
+  if (typeof input.type !== 'string' || input.type.trim().length === 0) {
+    return fail('Record type is required and must be a string');
+  }
+  const type = input.type.trim().toUpperCase();
+  if (ZONE_DELEGATION_TYPES.has(type)) {
+    return fail(
+      `Record type ${type} is not writable from Pulse — NS and SOA are zone-delegation records (D-01)`
+    );
+  }
+  if (!WRITABLE_RECORD_TYPES.includes(type as Route53WritableType)) {
+    return fail(
+      `Record type ${type} is not a supported writable type — must be one of ${WRITABLE_RECORD_TYPES.join(', ')}`
+    );
+  }
+
+  // 3. ttl: integer 0..2147483647 inclusive, default 300 when omitted.
+  let ttl: number;
+  if (input.ttl === undefined || input.ttl === null) {
+    ttl = 300;
+  } else {
+    if (typeof input.ttl !== 'number' || !Number.isInteger(input.ttl)) {
+      return fail('ttl must be an integer');
+    }
+    if (input.ttl < MIN_TTL || input.ttl > MAX_TTL) {
+      return fail(`ttl must be between ${MIN_TTL} and ${MAX_TTL}`);
+    }
+    ttl = input.ttl;
+  }
+
+  // 4. resourceRecords: non-empty array, each entry a non-empty string value,
+  // capped at 100 entries (Route 53 rejects an empty value set; unbounded
+  // arrays are a DoS surface — T-24-12).
+  if (!Array.isArray(input.resourceRecords) || input.resourceRecords.length === 0) {
+    return fail('resourceRecords must be a non-empty array');
+  }
+  if (input.resourceRecords.length > MAX_RESOURCE_RECORDS) {
+    return fail(`resourceRecords cannot exceed ${MAX_RESOURCE_RECORDS} entries`);
+  }
+  const resourceRecords: Route53RecordValue[] = [];
+  for (const entry of input.resourceRecords) {
+    if (
+      typeof entry !== 'object' ||
+      entry === null ||
+      typeof (entry as { value?: unknown }).value !== 'string' ||
+      (entry as { value: string }).value.trim().length === 0
+    ) {
+      return fail('Each resourceRecords entry must have a non-empty string value');
+    }
+    resourceRecords.push({ value: (entry as { value: string }).value });
+  }
+
+  return {
+    ok: true,
+    value: {
+      name,
+      type: type as Route53WritableType,
+      ttl,
+      resourceRecords,
+    },
+  };
+}
+
+const AWS_ACCESS_KEY_ID_PATTERN = /AKIA[0-9A-Z]{16}/g;
+const AWS_ARN_PATTERN = /arn:aws:[^\s"']+/g;
+const AWS_ACCOUNT_ID_PATTERN = /\b[0-9]{12}\b/g;
+const MAX_SANITIZED_LENGTH = 500;
+
+/**
+ * Redact anything that looks like an AWS access key id, ARN, or 12-digit
+ * account id from an AWS SDK error, then truncate. This is the only string
+ * that may be written to `route53_audit_log.error_message` or returned in an
+ * API response body (T-24-03). Never throws.
+ */
+export function sanitizeAwsError(err: unknown): string {
+  let message: string;
+  try {
+    message = err instanceof Error ? err.message : String(err);
+  } catch {
+    message = 'Unknown error';
+  }
+
+  let sanitized = message
+    .replace(AWS_ACCESS_KEY_ID_PATTERN, '[redacted-key-id]')
+    .replace(AWS_ARN_PATTERN, '[redacted-arn]')
+    .replace(AWS_ACCOUNT_ID_PATTERN, '[redacted-account-id]');
+
+  if (sanitized.length > MAX_SANITIZED_LENGTH) {
+    sanitized = `${sanitized.slice(0, MAX_SANITIZED_LENGTH)}...`;
+  }
+
+  return sanitized;
+}
diff --git a/lib/services/route53-write-persistence.test.ts b/lib/services/route53-write-persistence.test.ts
new file mode 100644
index 0000000..e442673
--- /dev/null
+++ b/lib/services/route53-write-persistence.test.ts
@@ -0,0 +1,180 @@
+/**
+ * lib/services/route53-write-persistence.ts unit tests — SQL contract checks
+ * against a mocked postgresClient. No real Postgres connection is made.
+ * Follows the mocking discipline in lib/services/pax8-sync-service.test.ts.
+ */
+
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+
+// Mock postgresClient BEFORE importing the module under test.
+const queryMock = vi.fn();
+vi.mock('@/lib/services/postgres-client', () => ({
+  default: {
+    query: (...args: unknown[]) => queryMock(...args),
+  },
+}));
+
+// Import AFTER the mock is declared so vi.mock hoisting takes effect.
+import {
+  createPendingAuditLog,
+  markAuditCommitted,
+  markAuditFailed,
+  insertPulseCrudHistory,
+  upsertMirrorRecord,
+  softDeleteMirrorRecord,
+  loadMirrorRecord,
+} from './route53-write-persistence';
+
+interface MockCall {
+  sql: string;
+  params: unknown[];
+}
+
+function calls(): MockCall[] {
+  return queryMock.mock.calls.map(([sql, params]) => ({
+    sql: String(sql),
+    params: (params as unknown[]) ?? [],
+  }));
+}
+
+beforeEach(() => {
+  queryMock.mockReset();
+});
+
+describe('createPendingAuditLog', () => {
+  it("issues an INSERT into route53_audit_log whose SQL contains 'pending'", async () => {
+    queryMock.mockResolvedValueOnce({ rows: [{ id: 'audit-1' }] });
+    const result = await createPendingAuditLog({
+      operation: 'create',
+      zoneId: 'Z123',
+      recordKey: 'Z123:www.example.com.:A:',
+      recordName: 'www.example.com.',
+      recordType: 'A',
+      beforeValue: null,
+      afterValue: { ttl: 300, resourceRecords: [{ value: '1.2.3.4' }] },
+      performedByUserId: 'user-1',
+      performedByEmail: 'lorentz@wulfconsulting.com',
+    });
+    expect(result).toEqual({ id: 'audit-1' });
+    expect(calls()).toHaveLength(1);
+    expect(calls()[0].sql).toContain('INSERT INTO route53_audit_log');
+    expect(calls()[0].sql).toContain("'pending'");
+  });
+});
+
+describe('markAuditCommitted', () => {
+  it("issues an UPDATE setting status = 'committed'", async () => {
+    queryMock.mockResolvedValueOnce({ rows: [] });
+    await markAuditCommitted('audit-1', 'change-1', 'INSYNC', { ResponseMetadata: {} });
+    expect(calls()[0].sql).toContain('UPDATE route53_audit_log');
+    expect(calls()[0].sql).toContain("'committed'");
+  });
+});
+
+describe('markAuditFailed', () => {
+  it('passes a sanitized error string — a raw AWS key id never reaches the bound parameters', async () => {
+    queryMock.mockResolvedValueOnce({ rows: [] });
+    const rawError = new Error('AccessDenied for AKIAIOSFODNN7EXAMPLE');
+    await markAuditFailed('audit-1', rawError);
+
+    expect(calls()).toHaveLength(1);
+    expect(calls()[0].sql).toContain("'failed'");
+    const boundParams = calls()[0].params;
+    expect(boundParams).not.toContain(rawError);
+    for (const param of boundParams) {
+      if (typeof param === 'string') {
+        expect(param).not.toContain('AKIAIOSFODNN7EXAMPLE');
+      }
+    }
+  });
+});
+
+describe('insertPulseCrudHistory', () => {
+  it("binds the literal 'pulse_crud' as the history source", async () => {
+    queryMock.mockResolvedValueOnce({ rows: [] });
+    await insertPulseCrudHistory({
+      zoneId: 'Z123',
+      recordKey: 'Z123:www.example.com.:A:',
+      recordName: 'www.example.com.',
+      recordType: 'A',
+      changeAction: 'create',
+      beforeValue: null,
+      afterValue: { ttl: 300 },
+      changedByUserId: 'user-1',
+      changedByEmail: 'lorentz@wulfconsulting.com',
+      auditLogId: 'audit-1',
+    });
+    expect(calls()[0].sql).toContain('INSERT INTO route53_record_history');
+    expect(calls()[0].sql).toContain("'pulse_crud'");
+  });
+});
+
+describe('upsertMirrorRecord', () => {
+  it('issues an INSERT ... ON CONFLICT upsert and never throws even if the query rejects', async () => {
+    queryMock.mockRejectedValueOnce(new Error('connection reset'));
+    await expect(
+      upsertMirrorRecord({
+        recordKey: 'Z123:www.example.com.:A:',
+        zoneId: 'Z123',
+        name: 'www.example.com.',
+        type: 'A',
+        setIdentifier: null,
+        ttl: 300,
+        resourceRecords: [{ value: '1.2.3.4' }],
+        aliasTarget: null,
+        rawPayload: null,
+      })
+    ).resolves.toBeUndefined();
+  });
+});
+
+describe('softDeleteMirrorRecord', () => {
+  it('issues an UPDATE and never a DELETE FROM', async () => {
+    queryMock.mockResolvedValueOnce({ rows: [] });
+    await softDeleteMirrorRecord('Z123:www.example.com.:A:');
+    expect(calls()[0].sql).toContain('UPDATE route53_records');
+    expect(calls()[0].sql).not.toContain('DELETE FROM');
+  });
+
+  it('never throws even if the query rejects (best-effort)', async () => {
+    queryMock.mockRejectedValueOnce(new Error('connection reset'));
+    await expect(softDeleteMirrorRecord('Z123:www.example.com.:A:')).resolves.toBeUndefined();
+  });
+});
+
+describe('loadMirrorRecord', () => {
+  it('returns a camelCase object when found', async () => {
+    queryMock.mockResolvedValueOnce({
+      rowCount: 1,
+      rows: [
+        {
+          record_key: 'Z123:www.example.com.:A:',
+          zone_id: 'Z123',
+          name: 'www.example.com.',
+          type: 'A',
+          set_identifier: null,
+          ttl: 300,
+          resource_records: [{ value: '1.2.3.4' }],
+          alias_target: null,
+        },
+      ],
+    });
+    const result = await loadMirrorRecord('Z123:www.example.com.:A:');
+    expect(result).toEqual({
+      recordKey: 'Z123:www.example.com.:A:',
+      zoneId: 'Z123',
+      name: 'www.example.com.',
+      type: 'A',
+      setIdentifier: null,
+      ttl: 300,
+      resourceRecords: [{ value: '1.2.3.4' }],
+      aliasTarget: null,
+    });
+  });
+
+  it('returns null when not found', async () => {
+    queryMock.mockResolvedValueOnce({ rowCount: 0, rows: [] });
+    const result = await loadMirrorRecord('missing-key');
+    expect(result).toBeNull();
+  });
+});
diff --git a/lib/services/route53-write-persistence.ts b/lib/services/route53-write-persistence.ts
new file mode 100644
index 0000000..1f0b83f
--- /dev/null
+++ b/lib/services/route53-write-persistence.ts
@@ -0,0 +1,297 @@
+/**
+ * AWS Route 53 DNS sync — CRUD write-back persistence.
+ *
+ * Implements the pending -> committed/failed audit lifecycle, the single
+ * most important pattern in this phase (lifted from
+ * lib/services/analyzer/asset-audit/persistence.ts's createPendingWrite /
+ * markWriteCommitted / markWriteFailed shape, itself following
+ * migrations/075_itglue_audit.sql's itglue_writes precedent).
+ *
+ * Discipline (24-RESEARCH.md Pattern 3, D-07): an audit row is created with
+ * status='pending' BEFORE any AWS command is constructed. It is then
+ * transitioned to 'committed' or 'failed' after the AWS call resolves.
+ * Callers must never construct a ChangeResourceRecordSetsCommand without an
+ * audit row already in flight.
+ */
+
+import postgresClient from '@/lib/services/postgres-client';
+import { sanitizeAwsError } from '@/lib/services/route53-record-validation';
+import type { Route53RecordValue } from '@/lib/types/route53';
+
+const LOG_PREFIX = '[ROUTE53-WRITE]';
+
+// ============================================================================
+// Audit lifecycle (route53_audit_log)
+// ============================================================================
+
+export interface CreatePendingAuditLogInput {
+  operation: 'create' | 'update' | 'delete';
+  zoneId: string;
+  recordKey: string;
+  recordName: string;
+  recordType: string;
+  beforeValue: unknown;
+  afterValue: unknown;
+  performedByUserId: string | null;
+  performedByEmail: string | null;
+}
+
+/**
+ * Insert a 'pending' audit row. Must be called and awaited BEFORE any AWS
+ * ChangeResourceRecordSetsCommand is constructed — that ordering is the
+ * whole point of this pattern: no write to Route 53 can occur without an
+ * audit row already in flight (D-07, SC-3). This write is not best-effort —
+ * let it throw so a DB failure fails the request rather than silently
+ * allowing an unlogged DNS mutation (T-24-07).
+ */
+export async function createPendingAuditLog(
+  input: CreatePendingAuditLogInput
+): Promise<{ id: string }> {
+  const res = await postgresClient.query<{ id: string }>(
+    `INSERT INTO route53_audit_log
+       (operation, zone_id, record_key, record_name, record_type,
+        before_value, after_value,
+        performed_by_user_id, performed_by_email, status)
+     VALUES ($1, $2, $3, $4, $5,
+             $6::jsonb, $7::jsonb,
+             $8, $9, 'pending')
+     RETURNING id::text AS id`,
+    [
+      input.operation,
+      input.zoneId,
+      input.recordKey,
+      input.recordName,
+      input.recordType,
+      JSON.stringify(input.beforeValue ?? null),
+      JSON.stringify(input.afterValue ?? null),
+      input.performedByUserId,
+      input.performedByEmail,
+    ]
+  );
+  return { id: res.rows[0].id };
+}
+
+/**
+ * Transition an audit row to 'committed' after a successful AWS call. Not
+ * best-effort — let it throw.
+ */
+export async function markAuditCommitted(
+  id: string,
+  awsChangeId: string | null,
+  awsChangeStatus: string | null,
+  awsResponse: unknown
+): Promise<void> {
+  await postgresClient.query(
+    `UPDATE route53_audit_log
+        SET status = 'committed',
+            completed_at = NOW(),
+            aws_change_id = $2,
+            aws_change_status = $3,
+            aws_response = $4::jsonb
+      WHERE id = $1`,
+    [id, awsChangeId, awsChangeStatus, JSON.stringify(awsResponse ?? null)]
+  );
+}
+
+/**
+ * Transition an audit row to 'failed' after an unsuccessful AWS call.
+ * D-07 + T-24-03: the error is always passed through sanitizeAwsError first
+ * — never pass a raw error object or JSON.stringify(err) into error_message.
+ * Not best-effort — let it throw.
+ */
+export async function markAuditFailed(id: string, err: unknown): Promise<void> {
+  await postgresClient.query(
+    `UPDATE route53_audit_log
+        SET status = 'failed',
+            completed_at = NOW(),
+            error_message = $2
+      WHERE id = $1`,
+    [id, sanitizeAwsError(err)]
+  );
+}
+
+// ============================================================================
+// pulse_crud history (route53_record_history)
+// ============================================================================
+
+export interface InsertPulseCrudHistoryInput {
+  zoneId: string;
+  recordKey: string;
+  recordName: string;
+  recordType: string;
+  changeAction: 'create' | 'update' | 'delete';
+  beforeValue: unknown;
+  afterValue: unknown;
+  changedByUserId: string | null;
+  changedByEmail: string | null;
+  auditLogId: string;
+}
+
+/**
+ * Insert a 'pulse_crud' history row.
+ *
+ * IMPORTANT: callers must invoke this ONLY after markAuditCommitted. A
+ * failed AWS call changed nothing on AWS's side, so it gets an audit row
+ * (for traceability of the attempt) but must NOT get a history row (which is
+ * a timeline of resolved, actually-applied changes). See 24-RESEARCH.md
+ * Pattern 3.
+ */
+export async function insertPulseCrudHistory(
+  input: InsertPulseCrudHistoryInput
+): Promise<void> {
+  await postgresClient.query(
+    `INSERT INTO route53_record_history
+       (zone_id, record_key, record_name, record_type,
+        change_action, before_value, after_value,
+        source, changed_by_user_id, changed_by_email, audit_log_id)
+     VALUES ($1, $2, $3, $4,
+             $5, $6::jsonb, $7::jsonb,
+             'pulse_crud', $8, $9, $10)`,
+    [
+      input.zoneId,
+      input.recordKey,
+      input.recordName,
+      input.recordType,
+      input.changeAction,
+      JSON.stringify(input.beforeValue ?? null),
+      JSON.stringify(input.afterValue ?? null),
+      input.changedByUserId,
+      input.changedByEmail,
+      input.auditLogId,
+    ]
+  );
+}
+
+// ============================================================================
+// Mirror refresh (route53_records) — best-effort
+// ============================================================================
+
+export interface UpsertMirrorRecordInput {
+  recordKey: string;
+  zoneId: string;
+  name: string;
+  type: string;
+  setIdentifier: string | null;
+  ttl: number | null;
+  resourceRecords: Route53RecordValue[] | null;
+  aliasTarget: Record<string, unknown> | null;
+  rawPayload: unknown;
+}
+
+/**
+ * Best-effort refresh of route53_records after a committed write so the
+ * admin UI reflects the change before the next scheduled sync. A failure
+ * here is logged but never thrown — the AWS write already succeeded and the
+ * next incremental sync reconciles the mirror regardless.
+ */
+export async function upsertMirrorRecord(input: UpsertMirrorRecordInput): Promise<void> {
+  try {
+    await postgresClient.query(
+      `INSERT INTO route53_records
+         (record_key, zone_id, name, type, set_identifier, ttl,
+          resource_records, alias_target, raw_payload,
+          synced_at, updated_at, is_deleted, deleted_at)
+       VALUES ($1, $2, $3, $4, $5, $6,
+               $7::jsonb, $8::jsonb, $9::jsonb,
+               NOW(), NOW(), false, NULL)
+       ON CONFLICT (record_key) DO UPDATE SET
+         zone_id = EXCLUDED.zone_id,
+         name = EXCLUDED.name,
+         type = EXCLUDED.type,
+         set_identifier = EXCLUDED.set_identifier,
+         ttl = EXCLUDED.ttl,
+         resource_records = EXCLUDED.resource_records,
+         alias_target = EXCLUDED.alias_target,
+         raw_payload = EXCLUDED.raw_payload,
+         synced_at = NOW(),
+         updated_at = NOW(),
+         is_deleted = false,
+         deleted_at = NULL`,
+      [
+        input.recordKey,
+        input.zoneId,
+        input.name,
+        input.type,
+        input.setIdentifier,
+        input.ttl,
+        JSON.stringify(input.resourceRecords ?? null),
+        JSON.stringify(input.aliasTarget ?? null),
+        JSON.stringify(input.rawPayload ?? null),
+      ]
+    );
+  } catch (err) {
+    console.error(`${LOG_PREFIX} upsertMirrorRecord failed (best-effort):`, sanitizeAwsError(err));
+  }
+}
+
+/**
+ * Soft-delete a mirror record. Never hard-delete: route53_record_history
+ * references record_key and the ledger is unbounded by design (D-08). Best
+ * effort — logged, never thrown.
+ */
+export async function softDeleteMirrorRecord(recordKey: string): Promise<void> {
+  try {
+    await postgresClient.query(
+      `UPDATE route53_records
+          SET is_deleted = true, deleted_at = NOW(), updated_at = NOW()
+        WHERE record_key = $1`,
+      [recordKey]
+    );
+  } catch (err) {
+    console.error(`${LOG_PREFIX} softDeleteMirrorRecord failed (best-effort):`, sanitizeAwsError(err));
+  }
+}
+
+// ============================================================================
+// Mirror read (route53_records)
+// ============================================================================
+
+export interface MirrorRecordRow {
+  recordKey: string;
+  zoneId: string;
+  name: string;
+  type: string;
+  setIdentifier: string | null;
+  ttl: number | null;
+  resourceRecords: Route53RecordValue[] | null;
+  aliasTarget: Record<string, unknown> | null;
+}
+
+interface RawMirrorRecordRow {
+  record_key: string;
+  zone_id: string;
+  name: string;
+  type: string;
+  set_identifier: string | null;
+  ttl: number | null;
+  resource_records: Route53RecordValue[] | null;
+  alias_target: Record<string, unknown> | null;
+}
+
+/**
+ * Load the current mirror row for a record key, if present and not
+ * soft-deleted. Supplies the before_value for updates/deletes and,
+ * critically, the exact TTL and value set a Route 53 DELETE action requires
+ * to match — a DELETE with a mismatched TTL or value set fails or targets
+ * the wrong recordset (24-RESEARCH.md Pitfall 3).
+ */
+export async function loadMirrorRecord(recordKey: string): Promise<MirrorRecordRow | null> {
+  const res = await postgresClient.query<RawMirrorRecordRow>(
+    `SELECT record_key, zone_id, name, type, set_identifier, ttl, resource_records, alias_target
+       FROM route53_records
+      WHERE record_key = $1 AND is_deleted = false`,
+    [recordKey]
+  );
+  if (res.rowCount === 0) return null;
+  const row = res.rows[0];
+  return {
+    recordKey: row.record_key,
+    zoneId: row.zone_id,
+    name: row.name,
+    type: row.type,
+    setIdentifier: row.set_identifier,
+    ttl: row.ttl,
+    resourceRecords: row.resource_records,
+    aliasTarget: row.alias_target,
+  };
+}