diff --git a/packages/objectql/src/bulk-write-per-row-hooks.test.ts b/packages/objectql/src/bulk-write-per-row-hooks.test.ts
index 778eb0db47..a5847b7a53 100644
--- a/packages/objectql/src/bulk-write-per-row-hooks.test.ts
+++ b/packages/objectql/src/bulk-write-per-row-hooks.test.ts
@@ -468,7 +468,7 @@ async function seedTasks(engine: ObjectQL, rows: Record<string, unknown>[]): Pro
   return Array.isArray(written) ? written : [written];
 }
 
-function makeMemoryDriver(): any {
+function makeStubDriver(): any {
   const stores = new Map<string, Map<string, Record<string, unknown>>>();
   const storeFor = (o: string) => {
     let s = stores.get(o);
@@ -528,7 +528,7 @@ function makeMemoryDriver(): any {
 
 async function boot(hooks: Hook[]): Promise<{ engine: ObjectQL; driver: any }> {
   const engine = new ObjectQL();
-  const driver = makeMemoryDriver();
+  const driver = makeStubDriver();
   engine.registerDriver(driver, true);
   await engine.init();
   engine.registry.registerObject(taskObject as any);
diff --git a/packages/objectql/src/engine-audit-anchor-write.test.ts b/packages/objectql/src/engine-audit-anchor-write.test.ts
index 7083b4ce3c..778b2b2b1d 100644
--- a/packages/objectql/src/engine-audit-anchor-write.test.ts
+++ b/packages/objectql/src/engine-audit-anchor-write.test.ts
@@ -4,7 +4,7 @@
  * [#4447] `created_at` is engine-owned: a client-supplied value on an ordinary
  * write is DROPPED, not persisted.
  *
- * Reproduction harness: a REAL {@link ObjectQL} engine over a minimal in-memory
+ * Reproduction harness: a REAL {@link ObjectQL} engine over a minimal stub
  * driver whose `update` lets incoming data win (`{...cur, ...data}`) — the same
  * shape driver-sql has, which is why a value that survives the engine's strip
  * reaches the row.
@@ -23,7 +23,7 @@ const taskObject = {
   },
 };
 
-function makeMemoryDriver() {
+function makeStubDriver() {
   const stores = new Map<string, Map<string, Record<string, unknown>>>();
   const storeFor = (obj: string) => {
     let s = stores.get(obj);
@@ -106,7 +106,7 @@ describe('[#4447] created_at is engine-owned on an ordinary write', () => {
 
   beforeEach(async () => {
     engine = new ObjectQL();
-    const { driver } = makeMemoryDriver();
+    const { driver } = makeStubDriver();
     engine.registerDriver(driver, true);
     await engine.init();
     engine.registry.registerObject(taskObject as any);
@@ -252,7 +252,7 @@ describe('[#4447] a declared audit field cannot loosen the platform posture', ()
   let engine: ObjectQL;
   beforeEach(async () => {
     engine = new ObjectQL();
-    const { driver } = makeMemoryDriver();
+    const { driver } = makeStubDriver();
     engine.registerDriver(driver, true);
     await engine.init();
     engine.registry.registerObject(shadowed as any);
diff --git a/packages/objectql/src/engine-autonumber-runtime-owned.test.ts b/packages/objectql/src/engine-autonumber-runtime-owned.test.ts
index 57be2578f1..1344a436ef 100644
--- a/packages/objectql/src/engine-autonumber-runtime-owned.test.ts
+++ b/packages/objectql/src/engine-autonumber-runtime-owned.test.ts
@@ -54,7 +54,7 @@ const ACCOUNT = {
   },
 };
 
-function makeMemoryDriver(opts: { nativeAutonumber?: boolean } = {}) {
+function makeStubDriver(opts: { nativeAutonumber?: boolean } = {}) {
   const stores = new Map<string, Map<string, Record<string, unknown>>>();
   const createdRows: Array<Record<string, unknown>> = [];
   const updatedPayloads: Array<Record<string, unknown>> = [];
@@ -153,7 +153,7 @@ function makeMemoryDriver(opts: { nativeAutonumber?: boolean } = {}) {
 
 async function makeEngine(opts: { nativeAutonumber?: boolean } = {}) {
   const engine = new ObjectQL();
-  const rig = makeMemoryDriver(opts);
+  const rig = makeStubDriver(opts);
   engine.registerDriver(rig.driver, true);
   await engine.init();
   engine.registry.registerObject(ACCOUNT as any);
diff --git a/packages/objectql/src/engine-cascade-delete.test.ts b/packages/objectql/src/engine-cascade-delete.test.ts
index f0fcfea9b5..858fec53e2 100644
--- a/packages/objectql/src/engine-cascade-delete.test.ts
+++ b/packages/objectql/src/engine-cascade-delete.test.ts
@@ -2,7 +2,7 @@
 
 /**
  * Cascade-on-delete behavior for parent→child foreign keys, with a REAL
- * {@link ObjectQL} engine + in-memory driver.
+ * {@link ObjectQL} engine + stub driver.
  *
  * Regression: deleting a parent whose child has a *required* lookup FK used to
  * default to `set_null`, issuing an UPDATE that cleared the required FK — which
@@ -56,7 +56,7 @@ const taskCascade = {
     },
 };
 
-function makeMemoryDriver() {
+function makeStubDriver() {
     const stores = new Map<string, Map<string, Record<string, unknown>>>();
     const storeFor = (o: string) => { let s = stores.get(o); if (!s) { s = new Map(); stores.set(o, s); } return s; };
     let nextId = 0;
@@ -96,7 +96,7 @@ describe('cascadeDeleteRelations — required FK escalates set_null → restrict
 
     beforeEach(async () => {
         engine = new ObjectQL();
-        const { driver } = makeMemoryDriver();
+        const { driver } = makeStubDriver();
         engine.registerDriver(driver, true);
         await engine.init();
         for (const o of [acct, oppRequired, noteOptional, taskCascade]) engine.registry.registerObject(o as any);
diff --git a/packages/objectql/src/engine-dangling-reference-audit.test.ts b/packages/objectql/src/engine-dangling-reference-audit.test.ts
index 8dee2a776f..a661a0dd04 100644
--- a/packages/objectql/src/engine-dangling-reference-audit.test.ts
+++ b/packages/objectql/src/engine-dangling-reference-audit.test.ts
@@ -61,7 +61,7 @@ const history = {
   },
 };
 
-function makeMemoryDriver() {
+function makeStubDriver() {
   const stores = new Map<string, Map<string, Record<string, unknown>>>();
   const storeFor = (obj: string) => {
     let s = stores.get(obj);
@@ -140,9 +140,9 @@ describe('[#4551] the engine reports the dangling rows its own `isSystem` exempt
 
   beforeEach(async () => {
     engine = new ObjectQL();
-    const mem = makeMemoryDriver();
-    stores = mem.stores;
-    engine.registerDriver(mem.driver, true);
+    const stub = makeStubDriver();
+    stores = stub.stores;
+    engine.registerDriver(stub.driver, true);
     await engine.init();
     engine.registry.registerObject(permissionSet as any);
     engine.registry.registerObject(binding as any);
diff --git a/packages/objectql/src/engine-data-events.bench.ts b/packages/objectql/src/engine-data-events.bench.ts
index e9de563a89..89be419ab8 100644
--- a/packages/objectql/src/engine-data-events.bench.ts
+++ b/packages/objectql/src/engine-data-events.bench.ts
@@ -15,7 +15,7 @@
  * Each pair below is the SAME write with and without a realtime service
  * attached, so the delta is exactly the event-publishing work: uuid generation,
  * schema validation, envelope construction, and the (no-op) publish. The
- * in-memory driver keeps driver cost near zero, which flatters the event cost —
+ * stub driver keeps driver cost near zero, which flatters the event cost —
  * i.e. the relative overhead measured here is an upper bound on what a real
  * SQL/HTTP driver would show.
  */
@@ -34,7 +34,7 @@ const task = {
   },
 };
 
-function makeMemoryDriver() {
+function makeStubDriver() {
   const stores = new Map<string, Map<string, Record<string, unknown>>>();
   const storeFor = (o: string) => {
     let s = stores.get(o);
@@ -102,7 +102,7 @@ const nullRealtime: IRealtimeService = {
 
 async function makeEngine(withRealtime: boolean): Promise<ObjectQL> {
   const engine = new ObjectQL();
-  engine.registerDriver(makeMemoryDriver(), true);
+  engine.registerDriver(makeStubDriver(), true);
   await engine.init();
   engine.registry.registerObject(task as any, 'bench');
   if (withRealtime) engine.setRealtimeService(nullRealtime);
diff --git a/packages/objectql/src/engine-data-events.test.ts b/packages/objectql/src/engine-data-events.test.ts
index 554f86f1bb..21eca1b1b6 100644
--- a/packages/objectql/src/engine-data-events.test.ts
+++ b/packages/objectql/src/engine-data-events.test.ts
@@ -43,7 +43,7 @@ const task = {
   },
 };
 
-function makeMemoryDriver() {
+function makeStubDriver() {
   const stores = new Map<string, Map<string, Record<string, unknown>>>();
   const storeFor = (o: string) => {
     let s = stores.get(o);
@@ -118,7 +118,7 @@ describe('#4626 — engine writes publish true DataEvents', () => {
       unsubscribe: vi.fn(async () => undefined),
     };
     engine = new ObjectQL();
-    const { driver } = makeMemoryDriver();
+    const { driver } = makeStubDriver();
     engine.registerDriver(driver, true);
     await engine.init();
     engine.registry.registerObject(task as any);
@@ -216,7 +216,7 @@ describe('#4626 — engine writes publish true DataEvents', () => {
 
   it('publishes nothing at all when no realtime service is configured', async () => {
     const bare = new ObjectQL();
-    const { driver } = makeMemoryDriver();
+    const { driver } = makeStubDriver();
     bare.registerDriver(driver, true);
     await bare.init();
     bare.registry.registerObject(task as any);
@@ -253,7 +253,7 @@ describe('#4639 — predicate writes publish aggregate BulkDataEvents', () => {
       unsubscribe: vi.fn(async () => undefined),
     };
     engine = new ObjectQL();
-    const { driver } = makeMemoryDriver();
+    const { driver } = makeStubDriver();
     engine.registerDriver(driver, true);
     await engine.init();
     engine.registry.registerObject(task as any);
@@ -351,7 +351,7 @@ describe('#4639 — predicate writes publish aggregate BulkDataEvents', () => {
 
   it('publishes NOTHING when the driver breaks its count contract — and says so', async () => {
     const offContract = new ObjectQL();
-    const { driver } = makeMemoryDriver();
+    const { driver } = makeStubDriver();
     // `updateMany` is contracted to resolve the affected count. A driver that
     // resolves something else leaves `matched` unknowable, and `matched` is the
     // entire substance of a bulk event — so none is published.
diff --git a/packages/objectql/src/engine-default-value-tokens.test.ts b/packages/objectql/src/engine-default-value-tokens.test.ts
index 4ea1f4cadb..02349972c7 100644
--- a/packages/objectql/src/engine-default-value-tokens.test.ts
+++ b/packages/objectql/src/engine-default-value-tokens.test.ts
@@ -33,7 +33,7 @@ import { DEFAULT_VALUE_TOKEN_CURRENT_USER, DEFAULT_VALUE_TOKEN_NOW } from '@obje
 /** `YYYY-MM-DDTHH:MM:SS.sssZ` — the canonical stored instant (ADR-0053). */
 const ISO_INSTANT = /^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}\.\d{3}Z$/;
 
-function makeMemoryDriver() {
+function makeStubDriver() {
   const stores = new Map<string, Map<string, Record<string, unknown>>>();
   const storeFor = (obj: string) => {
     let s = stores.get(obj);
@@ -88,7 +88,7 @@ describe('[#4560] the `current_user` defaultValue token is engine-owned', () =>
 
   beforeEach(async () => {
     engine = new ObjectQL();
-    engine.registerDriver(makeMemoryDriver().driver, true);
+    engine.registerDriver(makeStubDriver().driver, true);
     await engine.init();
     engine.registry.registerObject(owned as any);
   });
@@ -145,7 +145,7 @@ describe('[#4597] the `NOW()` defaultValue token is engine-owned too', () => {
 
   beforeEach(async () => {
     engine = new ObjectQL();
-    engine.registerDriver(makeMemoryDriver().driver, true);
+    engine.registerDriver(makeStubDriver().driver, true);
     await engine.init();
     engine.registry.registerObject(stamped as any);
   });
@@ -154,7 +154,8 @@ describe('[#4597] the `NOW()` defaultValue token is engine-owned too', () => {
     // Before the fix this threw `ValidationError: seen_at must be a valid
     // datetime (ISO-8601)`: the engine filled the field with the literal
     // string 'NOW()' and its own validator then rejected the insert. The
-    // memory driver has no `formatInput` safety net to hide it behind.
+    // stub driver, like every non-SQL driver, has no `formatInput` safety net
+    // to hide it behind.
     const row: any = await engine.insert('probe_now', {}, { context: { isSystem: true } } as any);
     expect(row.seen_at).not.toBe('NOW()');
     expect(row.seen_at).toMatch(ISO_INSTANT);
diff --git a/packages/objectql/src/engine-filter-alias.test.ts b/packages/objectql/src/engine-filter-alias.test.ts
index 059170db5d..12289896b4 100644
--- a/packages/objectql/src/engine-filter-alias.test.ts
+++ b/packages/objectql/src/engine-filter-alias.test.ts
@@ -2,7 +2,7 @@
 
 /**
  * #4346 — the `filter` → `where` alias folds on EVERY engine entry point, not
- * just `find()`, with a REAL {@link ObjectQL} engine + in-memory driver.
+ * just `find()`, with a REAL {@link ObjectQL} engine + stub driver.
  *
  * Regression: the DataEngine contract (`DataEngine*OptionsSchema`) declares
  * `filter` as a legitimate option on every read and write method, but only
@@ -37,7 +37,7 @@ const task = {
     },
 };
 
-function makeMemoryDriver() {
+function makeStubDriver() {
     const stores = new Map<string, Map<string, Record<string, unknown>>>();
     const storeFor = (o: string) => { let s = stores.get(o); if (!s) { s = new Map(); stores.set(o, s); } return s; };
     let nextId = 0;
@@ -99,9 +99,9 @@ describe('filter → where folds on every engine method (#4346)', () => {
 
     beforeEach(async () => {
         engine = new ObjectQL();
-        const mem = makeMemoryDriver();
-        stores = mem.stores;
-        engine.registerDriver(mem.driver, true);
+        const stub = makeStubDriver();
+        stores = stub.stores;
+        engine.registerDriver(stub.driver, true);
         await engine.init();
         engine.registry.registerObject(task as any);
         // The issue's repro set: one open row, two done rows.
diff --git a/packages/objectql/src/engine-lookup-referential-integrity.test.ts b/packages/objectql/src/engine-lookup-referential-integrity.test.ts
index fb044983cd..3c8326e17d 100644
--- a/packages/objectql/src/engine-lookup-referential-integrity.test.ts
+++ b/packages/objectql/src/engine-lookup-referential-integrity.test.ts
@@ -67,7 +67,7 @@ const task = {
   },
 };
 
-function makeMemoryDriver() {
+function makeStubDriver() {
   const stores = new Map<string, Map<string, Record<string, unknown>>>();
   const storeFor = (obj: string) => {
     let s = stores.get(obj);
@@ -150,9 +150,9 @@ describe('[#4441] a lookup id that resolves to nothing is refused', () => {
 
   beforeEach(async () => {
     engine = new ObjectQL();
-    const mem = makeMemoryDriver();
-    stores = mem.stores;
-    engine.registerDriver(mem.driver, true);
+    const stub = makeStubDriver();
+    stores = stub.stores;
+    engine.registerDriver(stub.driver, true);
     await engine.init();
     engine.registry.registerObject(permissionSet as any);
     engine.registry.registerObject(binding as any);
diff --git a/packages/objectql/src/engine-write-formula-hydration.test.ts b/packages/objectql/src/engine-write-formula-hydration.test.ts
index 537a453465..c430c6077d 100644
--- a/packages/objectql/src/engine-write-formula-hydration.test.ts
+++ b/packages/objectql/src/engine-write-formula-hydration.test.ts
@@ -125,7 +125,7 @@ const MEMO = {
   },
 };
 
-function makeMemoryDriver() {
+function makeStubDriver() {
   const stores = new Map<string, Map<string, Record<string, unknown>>>();
   const storeFor = (obj: string) => {
     let s = stores.get(obj);
@@ -154,14 +154,15 @@ function makeMemoryDriver() {
     async disconnect() {},
     async checkHealth() { return true; },
     async execute() { return null; },
-    // Shallow COPIES, never live references into the backing table — the
-    // contract `driver-memory` states in as many words, and the SQL driver gets
-    // for free from knex. It is load-bearing for this file specifically: the
-    // READ path hydrates formulas by mutating the rows a driver hands back, so
-    // a harness leaking references would write `display_title` into its own
-    // store on the first GET and every later write response would echo it —
-    // these tests would then pass with the write-path hydration deleted, which
-    // is the "green because nothing is produced" failure mode, inverted.
+    // Shallow COPIES, never live references into the backing table — the shape
+    // every real backend hands back (a SQL driver gets it for free from knex; an
+    // in-process store has to copy explicitly). It is load-bearing for this
+    // file specifically: the READ path hydrates formulas by mutating the rows a
+    // driver hands back, so a harness leaking references would write
+    // `display_title` into its own store on the first GET and every later
+    // write response would echo it — these tests would then pass with the
+    // write-path hydration deleted, which is the "green because nothing is
+    // produced" failure mode, inverted.
     async find(object: string, ast: { where?: unknown }) {
       return Array.from(storeFor(object).values())
         .filter((r) => matchesWhere(r, ast?.where))
@@ -222,7 +223,7 @@ function makeMemoryDriver() {
 
 async function makeEngine() {
   const engine = new ObjectQL();
-  const rig = makeMemoryDriver();
+  const rig = makeStubDriver();
   engine.registerDriver(rig.driver as never, true);
   await engine.init();
   for (const obj of [ACCOUNT, FORECAST, PLAIN, MEMO]) {
diff --git a/packages/objectql/src/hook-condition-bulk-previous.test.ts b/packages/objectql/src/hook-condition-bulk-previous.test.ts
index c4d5d38e72..5ff85c81a3 100644
--- a/packages/objectql/src/hook-condition-bulk-previous.test.ts
+++ b/packages/objectql/src/hook-condition-bulk-previous.test.ts
@@ -479,7 +479,7 @@ describe('[#5038] the diagnostic is RETIRED for after-type hooks', () => {
  * Real-engine harness (mirrors hook-condition-fail-loud.test.ts)
  * ──────────────────────────────────────────────────────────────────────────── */
 
-function makeMemoryDriver(): any {
+function makeStubDriver(): any {
   const stores = new Map<string, Map<string, Record<string, unknown>>>();
   const storeFor = (o: string) => {
     let s = stores.get(o);
@@ -534,7 +534,7 @@ function makeMemoryDriver(): any {
 
 async function bootEngine(hooks: Hook[]): Promise<ObjectQL> {
   const engine = new ObjectQL();
-  engine.registerDriver(makeMemoryDriver(), true);
+  engine.registerDriver(makeStubDriver(), true);
   await engine.init();
   engine.registry.registerObject(taskObject as any);
   bindHooksToEngine(engine, hooks, { packageId: 'app:test', logger: silentLogger });
diff --git a/packages/objectql/src/hook-condition-fail-loud.test.ts b/packages/objectql/src/hook-condition-fail-loud.test.ts
index 648dad7077..c60f9e0b1a 100644
--- a/packages/objectql/src/hook-condition-fail-loud.test.ts
+++ b/packages/objectql/src/hook-condition-fail-loud.test.ts
@@ -458,7 +458,7 @@ describe('[#4775] a condition that does not compile aborts too', () => {
  * Real-engine harness
  * ──────────────────────────────────────────────────────────────────────────── */
 
-function makeMemoryDriver(): any {
+function makeStubDriver(): any {
   const stores = new Map<string, Map<string, Record<string, unknown>>>();
   const storeFor = (o: string) => {
     let s = stores.get(o);
@@ -508,7 +508,7 @@ function makeMemoryDriver(): any {
 
 async function bootEngine(hooks: Hook[]): Promise<ObjectQL> {
   const engine = new ObjectQL();
-  engine.registerDriver(makeMemoryDriver(), true);
+  engine.registerDriver(makeStubDriver(), true);
   await engine.init();
   engine.registry.registerObject(taskObject as any);
   bindHooksToEngine(engine, hooks, { packageId: 'app:test', logger: silentLogger });
diff --git a/packages/objectql/src/hook-condition-merged-record.test.ts b/packages/objectql/src/hook-condition-merged-record.test.ts
index 2622cda987..a4e7a2116d 100644
--- a/packages/objectql/src/hook-condition-merged-record.test.ts
+++ b/packages/objectql/src/hook-condition-merged-record.test.ts
@@ -226,12 +226,12 @@ describe('[#4770] hook condition evaluates against stored ⊕ payload', () => {
  *
  * `rm -rf examples/app-showcase/.objectstack && pnpm dev` printed ten
  * `condition evaluation failed` lines for `showcase_audit_task_completion`.
- * This is the same object/hook shape driven through a REAL engine over an
- * in-memory driver that — like a SQL driver — stores only the columns a write
+ * This is the same object/hook shape driven through a REAL engine over a
+ * stub driver that — like a SQL driver — stores only the columns a write
  * actually touched.
  * ──────────────────────────────────────────────────────────────────────────── */
 
-function makeMemoryDriver() {
+function makeStubDriver() {
   const stores = new Map<string, Map<string, Record<string, unknown>>>();
   const storeFor = (obj: string) => {
     let s = stores.get(obj);
@@ -309,7 +309,7 @@ describe('[#4770] showcase repro — showcase_audit_task_completion over a real
 
   beforeEach(async () => {
     engine = new ObjectQL();
-    const { driver } = makeMemoryDriver();
+    const { driver } = makeStubDriver();
     engine.registerDriver(driver, true);
     await engine.init();
     engine.registry.registerObject(taskObject as any);
diff --git a/packages/objectql/src/hook-condition-previous-scope.test.ts b/packages/objectql/src/hook-condition-previous-scope.test.ts
index 0c39a684ec..9820482d8f 100644
--- a/packages/objectql/src/hook-condition-previous-scope.test.ts
+++ b/packages/objectql/src/hook-condition-previous-scope.test.ts
@@ -268,11 +268,11 @@ describe('[#4784] hook condition binds `previous` alongside `record`', () => {
 });
 
 /* ────────────────────────────────────────────────────────────────────────────
- * Through a REAL engine, over an in-memory driver that — like a SQL driver —
+ * Through a REAL engine, over a stub driver that — like a SQL driver —
  * stores only the columns a write actually touched.
  * ──────────────────────────────────────────────────────────────────────────── */
 
-function makeMemoryDriver() {
+function makeStubDriver() {
   const stores = new Map<string, Map<string, Record<string, unknown>>>();
   /** Every read the engine performs, so "no extra fetch" is measurable. */
   const reads = { findOne: 0, find: 0 };
@@ -355,9 +355,9 @@ describe('[#4784] transition condition over a real engine', () => {
 
   async function boot(hooks: Hook[]) {
     engine = new ObjectQL();
-    const mem = makeMemoryDriver();
-    reads = mem.reads;
-    engine.registerDriver(mem.driver, true);
+    const stub = makeStubDriver();
+    reads = stub.reads;
+    engine.registerDriver(stub.driver, true);
     await engine.init();
     engine.registry.registerObject(taskObject as any);
 
@@ -446,15 +446,15 @@ describe('[#4784] a condition that never mentions `previous` costs zero extra fe
    */
   async function bootWith(hooks: Hook[]) {
     const engine = new ObjectQL();
-    const mem = makeMemoryDriver();
-    engine.registerDriver(mem.driver, true);
+    const stub = makeStubDriver();
+    engine.registerDriver(stub.driver, true);
     await engine.init();
     engine.registry.registerObject(taskObject as any);
     bindHooksToEngine(engine, hooks, {
       packageId: 'app:pin',
       logger: { debug: () => {}, info: () => {}, warn: () => {}, error: () => {} },
     });
-    return { engine, reads: mem.reads };
+    return { engine, reads: stub.reads };
   }
 
   it('reads no prior row at all for a before-hook condition over `record` only', async () => {
@@ -518,8 +518,8 @@ describe('[#4784] a condition that never mentions `previous` costs zero extra fe
 describe('[#5272] a single-record delete binds `previous` through the real engine', () => {
   async function bootDelete(hooks: Hook[]) {
     const engine = new ObjectQL();
-    const mem = makeMemoryDriver();
-    engine.registerDriver(mem.driver, true);
+    const stub = makeStubDriver();
+    engine.registerDriver(stub.driver, true);
     await engine.init();
     engine.registry.registerObject(taskObject as any);
     const warn = vi.fn();
@@ -529,7 +529,7 @@ describe('[#5272] a single-record delete binds `previous` through the real engin
     });
     return {
       engine,
-      reads: mem.reads,
+      reads: stub.reads,
       conditionWarnings: () =>
         warn.mock.calls.filter(([msg]) => String(msg).includes('condition evaluation failed')),
     };
diff --git a/packages/objectql/src/hook-input-shape-contract.test.ts b/packages/objectql/src/hook-input-shape-contract.test.ts
index 961bf1312c..9695fcbbbf 100644
--- a/packages/objectql/src/hook-input-shape-contract.test.ts
+++ b/packages/objectql/src/hook-input-shape-contract.test.ts
@@ -251,7 +251,7 @@ describe('[#5273] a metadata-declared hook reads the same shape', () => {
 });
 
 /* ────────────────────────────────────────────────────────────────────────────
- * Harness — a memory driver just wide enough for the dispatch paths above.
+ * Harness — a stub driver just wide enough for the dispatch paths above.
  * ──────────────────────────────────────────────────────────────────────────── */
 
 async function seedTasks(engine: ObjectQL, rows: Record<string, unknown>[]): Promise<any[]> {
@@ -259,7 +259,7 @@ async function seedTasks(engine: ObjectQL, rows: Record<string, unknown>[]): Pro
   return Array.isArray(written) ? written : [written];
 }
 
-function makeMemoryDriver(): any {
+function makeStubDriver(): any {
   const stores = new Map<string, Map<string, Record<string, unknown>>>();
   const storeFor = (o: string) => {
     let s = stores.get(o);
@@ -316,7 +316,7 @@ function makeMemoryDriver(): any {
 
 async function boot(): Promise<{ engine: ObjectQL; driver: any }> {
   const engine = new ObjectQL();
-  const driver = makeMemoryDriver();
+  const driver = makeStubDriver();
   engine.registerDriver(driver, true);
   await engine.init();
   engine.registry.registerObject(taskObject as any);
diff --git a/packages/objectql/src/protocol-clone-real-engine.test.ts b/packages/objectql/src/protocol-clone-real-engine.test.ts
index f7bf2b645c..ecc44e8f70 100644
--- a/packages/objectql/src/protocol-clone-real-engine.test.ts
+++ b/packages/objectql/src/protocol-clone-real-engine.test.ts
@@ -2,7 +2,7 @@
 
 /**
  * Integration test for `protocol.cloneData` driving a REAL {@link ObjectQL}
- * engine + a minimal in-memory driver. The unit suite in
+ * engine + a minimal stub driver. The unit suite in
  * `protocol-data.test.ts` stubs the engine; this exercises the production
  * path — registry.getObject (enable.clone + field defs), engine.findOne for
  * the source, and engine.insert for the copy — so the strongest real-engine
@@ -39,7 +39,7 @@ const lockedObject = {
     },
 };
 
-function makeMemoryDriver() {
+function makeStubDriver() {
     const stores = new Map<string, Map<string, Record<string, unknown>>>();
     const storeFor = (obj: string) => {
         let s = stores.get(obj);
@@ -113,7 +113,7 @@ describe('cloneData — real ObjectQL engine', () => {
 
     beforeEach(async () => {
         engine = new ObjectQL();
-        const { driver } = makeMemoryDriver();
+        const { driver } = makeStubDriver();
         engine.registerDriver(driver, true);
         await engine.init();
         engine.registry.registerObject(accountObject as any);
diff --git a/packages/objectql/src/protocol-recorded-by-null.test.ts b/packages/objectql/src/protocol-recorded-by-null.test.ts
index 98699969a6..4b43e85587 100644
--- a/packages/objectql/src/protocol-recorded-by-null.test.ts
+++ b/packages/objectql/src/protocol-recorded-by-null.test.ts
@@ -76,8 +76,8 @@ const sysMetadataHistoryObject = {
     },
 };
 
-/** Minimal in-memory driver; equality-only WHERE. */
-function makeMemoryDriver() {
+/** Minimal stub driver; equality-only WHERE. */
+function makeStubDriver() {
     const stores = new Map<string, Map<string, Record<string, unknown>>>();
     const storeFor = (obj: string) => {
         let s = stores.get(obj);
@@ -157,7 +157,7 @@ describe('#4556 — protocol write paths store NULL, not the sentinel string', (
 
     beforeEach(async () => {
         engine = new ObjectQL();
-        const { driver } = makeMemoryDriver();
+        const { driver } = makeStubDriver();
         engine.registerDriver(driver, true);
         await engine.init();
         engine.registry.registerObject(sysUserObject as any);
diff --git a/packages/objectql/src/protocol-registry-shadow.test.ts b/packages/objectql/src/protocol-registry-shadow.test.ts
index 7735eaa393..22515d1bf2 100644
--- a/packages/objectql/src/protocol-registry-shadow.test.ts
+++ b/packages/objectql/src/protocol-registry-shadow.test.ts
@@ -68,8 +68,8 @@ const sysMetadataHistoryObject = {
     },
 };
 
-/** Equality-only in-memory driver — same shape as the PR-10d.4 suite. */
-function makeMemoryDriver() {
+/** Equality-only stub driver — same shape as the PR-10d.4 suite. */
+function makeStubDriver() {
     const stores = new Map<string, Map<string, Record<string, unknown>>>();
     const storeFor = (obj: string) => {
         let s = stores.get(obj);
@@ -171,7 +171,7 @@ describe('registry shadow — control-plane PUT → GET → DELETE keeps the art
 
     beforeEach(async () => {
         engine = new ObjectQL();
-        const { driver } = makeMemoryDriver();
+        const { driver } = makeStubDriver();
         engine.registerDriver(driver, true);
         await engine.init();
         engine.registry.registerObject(sysMetadataObject as any);
diff --git a/packages/objectql/src/protocol-save-meta-repo-path-real-engine.test.ts b/packages/objectql/src/protocol-save-meta-repo-path-real-engine.test.ts
index 5acdc09da1..eca218be8f 100644
--- a/packages/objectql/src/protocol-save-meta-repo-path-real-engine.test.ts
+++ b/packages/objectql/src/protocol-save-meta-repo-path-real-engine.test.ts
@@ -2,7 +2,7 @@
 
 /**
  * PR-10d.4 — Integration test for the repository write path using a REAL
- * {@link ObjectQL} engine driving a minimal in-memory driver. The PR-10d.3
+ * {@link ObjectQL} engine driving a minimal stub driver. The PR-10d.3
  * unit suite uses a hand-rolled stub at the *engine* level; the rubber-duck
  * review flagged that as a drift risk because production semantics
  * (especially the strict `where: { id }` requirement for `engine.update`)
@@ -32,10 +32,10 @@ const sysMetadataObject = {
 };
 
 /**
- * Minimal in-memory driver covering only what `SysMetadataRepository`
+ * Minimal stub driver covering only what `SysMetadataRepository`
  * exercises. Equality-only WHERE evaluation; one record store per object.
  */
-function makeMemoryDriver() {
+function makeStubDriver() {
     const stores = new Map<string, Map<string, Record<string, unknown>>>();
     const storeFor = (obj: string) => {
         let s = stores.get(obj);
@@ -124,7 +124,7 @@ describe('saveMetaItem — repository write path against real ObjectQL (PR-10d.4
 
     beforeEach(async () => {
         engine = new ObjectQL();
-        const { driver } = makeMemoryDriver();
+        const { driver } = makeStubDriver();
         engine.registerDriver(driver, true);
         await engine.init();
         engine.registry.registerObject(sysMetadataObject as any);
@@ -224,7 +224,7 @@ describe('deleteMetaItem — repository write path against real ObjectQL (PR-10d
 
     beforeEach(async () => {
         engine = new ObjectQL();
-        const { driver } = makeMemoryDriver();
+        const { driver } = makeStubDriver();
         engine.registerDriver(driver, true);
         await engine.init();
         engine.registry.registerObject(sysMetadataObject as any);
diff --git a/packages/objectql/src/protocol-unknown-query-param.test.ts b/packages/objectql/src/protocol-unknown-query-param.test.ts
index e7b3c0b7aa..293129582d 100644
--- a/packages/objectql/src/protocol-unknown-query-param.test.ts
+++ b/packages/objectql/src/protocol-unknown-query-param.test.ts
@@ -35,7 +35,7 @@ const taskObject = {
     },
 };
 
-function makeMemoryDriver() {
+function makeStubDriver() {
     const stores = new Map<string, Map<string, Record<string, unknown>>>();
     const storeFor = (obj: string) => {
         let s = stores.get(obj);
@@ -121,7 +121,7 @@ describe('#4134 — unknown list query params (real ObjectQL engine)', () => {
 
     beforeEach(async () => {
         engine = new ObjectQL();
-        const { driver, stores } = makeMemoryDriver();
+        const { driver, stores } = makeStubDriver();
         engine.registerDriver(driver, true);
         await engine.init();
         engine.registry.registerObject(taskObject as any, 'test-package');
diff --git a/packages/objectql/src/protocol-unregistered-object.test.ts b/packages/objectql/src/protocol-unregistered-object.test.ts
index d347b63066..f481474532 100644
--- a/packages/objectql/src/protocol-unregistered-object.test.ts
+++ b/packages/objectql/src/protocol-unregistered-object.test.ts
@@ -20,7 +20,7 @@
  * after `syncObjectSchema` ran, a registration race — the exposure gate was
  * silently skipped AND nothing turned it into a 404. The rows were served.
  *
- * These tests drive a REAL {@link ObjectQL} engine + a minimal in-memory driver
+ * These tests drive a REAL {@link ObjectQL} engine + a minimal stub driver
  * (the same shape `protocol-clone-real-engine.test.ts` uses), because the point
  * is precisely what happens when metadata and physical storage disagree — which
  * an engine double cannot show.
@@ -42,7 +42,7 @@ const registeredObject = {
 /** The object nobody registered. A table by this name exists anyway (case B). */
 const UNREGISTERED = 'gate_ghost';
 
-function makeMemoryDriver() {
+function makeStubDriver() {
     const stores = new Map<string, Map<string, Record<string, unknown>>>();
     const storeFor = (obj: string) => {
         let s = stores.get(obj);
@@ -122,7 +122,7 @@ describe('#3770 — data-plane object-existence gate (real ObjectQL engine)', ()
 
     beforeEach(async () => {
         engine = new ObjectQL();
-        const made = makeMemoryDriver();
+        const made = makeStubDriver();
         stores = made.stores;
         engine.registerDriver(made.driver, true);
         await engine.init();
diff --git a/packages/objectql/src/query-expression-conformance.test.ts b/packages/objectql/src/query-expression-conformance.test.ts
index 1487537776..40e200f2fa 100644
--- a/packages/objectql/src/query-expression-conformance.test.ts
+++ b/packages/objectql/src/query-expression-conformance.test.ts
@@ -82,13 +82,13 @@ const taskObject = {
 };
 
 /**
- * An in-memory driver that really sorts, really projects and really paginates.
+ * A stub driver that really sorts, really projects and really paginates.
  *
  * This matters more than usual here: a driver that ignored `orderBy` would make
  * every "a real sort field works" control vacuously true, and the pins above it
  * would then pass against a completely broken sort axis.
  */
-function makeMemoryDriver() {
+function makeStubDriver() {
     const stores = new Map<string, Map<string, Record<string, unknown>>>();
     const storeFor = (obj: string) => {
         let s = stores.get(obj);
@@ -210,7 +210,7 @@ describe('#4226 — sort / select / expand on the list path (real ObjectQL engin
 
     beforeEach(async () => {
         engine = new ObjectQL();
-        const made = makeMemoryDriver();
+        const made = makeStubDriver();
         const driver = made.driver;
         stores = made.stores;
         engine.registerDriver(driver, true);
@@ -795,7 +795,7 @@ describe('#4254 — searchFields / groupBy / aggregations on the list path (real
 
     beforeEach(async () => {
         engine = new ObjectQL();
-        const { driver, stores } = makeMemoryDriver();
+        const { driver, stores } = makeStubDriver();
         // The issue's transcript runs on the engine's IN-MEMORY aggregation
         // fallback — the path `engine.aggregate` takes for drivers with no
         // native `aggregate` (driver-rest, driver-memory, partial SQL
diff --git a/packages/objectql/src/secret-fields.test.ts b/packages/objectql/src/secret-fields.test.ts
index cf70800246..adc09dc38d 100644
--- a/packages/objectql/src/secret-fields.test.ts
+++ b/packages/objectql/src/secret-fields.test.ts
@@ -2,7 +2,7 @@
 
 /**
  * Secret-field channel — end-to-end against a REAL {@link ObjectQL} engine + a
- * minimal in-memory driver. Verifies the core encryption chain:
+ * minimal stub driver. Verifies the core encryption chain:
  *  - encrypt-on-write: plaintext → sys_secret ciphertext + opaque ref on the row
  *  - mask-on-read: the generic read path never returns plaintext or the ref
  *  - resolveSecret: privileged dereference round-trips back to plaintext
@@ -15,8 +15,8 @@ import { ObjectQL } from './engine.js';
 import { SECRET_MASK, isSecretRef } from './secret-fields.js';
 import type { ICryptoProvider, CryptoHandle, CryptoContext } from '@objectstack/spec/contracts';
 
-// ---- minimal in-memory driver (equality-only WHERE) -----------------------
-function makeMemoryDriver() {
+// ---- minimal stub driver (equality-only WHERE) ----------------------------
+function makeStubDriver() {
   const stores = new Map<string, Map<string, Record<string, unknown>>>();
   const storeFor = (obj: string) => {
     let s = stores.get(obj);
@@ -130,7 +130,7 @@ const dsObject = {
 
 async function buildEngine(withCrypto: boolean) {
   const engine = new ObjectQL();
-  const { driver, stores } = makeMemoryDriver();
+  const { driver, stores } = makeStubDriver();
   engine.registerDriver(driver, true);
   await engine.init();
   engine.registry.registerObject(sysSecretObject as any);
@@ -216,7 +216,7 @@ describe('objectql secret-field channel', () => {
   it('non-secret objects are untouched (no crypto cost)', async () => {
     engineWithoutSecretField: {
       const engine = new ObjectQL();
-      const { driver, stores } = makeMemoryDriver();
+      const { driver, stores } = makeStubDriver();
       engine.registerDriver(driver, true);
       await engine.init();
       engine.registry.registerObject({
@@ -256,7 +256,7 @@ const authUserObject = {
 async function buildPasswordEngine() {
   // Deliberately NO CryptoProvider — a password field must not require one.
   const engine = new ObjectQL();
-  const { driver, stores } = makeMemoryDriver();
+  const { driver, stores } = makeStubDriver();
   engine.registerDriver(driver, true);
   await engine.init();
   engine.registry.registerObject(deviceObject as any);
diff --git a/packages/runtime/src/sandbox/nested-write.canary.test.ts b/packages/runtime/src/sandbox/nested-write.canary.test.ts
index c8a3424dbb..db3eebf224 100644
--- a/packages/runtime/src/sandbox/nested-write.canary.test.ts
+++ b/packages/runtime/src/sandbox/nested-write.canary.test.ts
@@ -55,7 +55,7 @@ const child = {
   },
 };
 
-function makeMemoryDriver() {
+function makeStubDriver() {
   const stores = new Map<string, Map<string, Record<string, unknown>>>();
   const storeFor = (o: string) => {
     let s = stores.get(o);
@@ -128,7 +128,7 @@ describe('#3259 flake canary — nested writes stay green at the stock 250ms CPU
 
   async function rollupChain(n: number) {
     const engine = new ObjectQL();
-    const { driver } = makeMemoryDriver();
+    const { driver } = makeStubDriver();
     engine.registerDriver(driver, true);
     await engine.init();
     for (const o of [parent, child]) engine.registry.registerObject(o as any);
diff --git a/packages/runtime/src/sandbox/nested-write.integration.test.ts b/packages/runtime/src/sandbox/nested-write.integration.test.ts
index 2ff9cc3d45..8bbde74aeb 100644
--- a/packages/runtime/src/sandbox/nested-write.integration.test.ts
+++ b/packages/runtime/src/sandbox/nested-write.integration.test.ts
@@ -8,7 +8,7 @@
  * hook, so the child's nested write fires a SECOND sandbox VM while the child's
  * hook is still in flight — the exact re-entrancy that used to crash the process
  * with `memory access out of bounds` under the old single-suspended-asyncify
- * model. This wires a REAL {@link ObjectQL} engine (in-memory driver) to the
+ * model. This wires a REAL {@link ObjectQL} engine (stub driver) to the
  * real {@link QuickJSScriptRunner} through {@link hookBodyRunnerFactory}, so the
  * whole hook → sandbox → nested-write → nested-hook path is exercised.
  *
@@ -41,7 +41,7 @@ const child = {
   },
 };
 
-function makeMemoryDriver() {
+function makeStubDriver() {
   const stores = new Map<string, Map<string, Record<string, unknown>>>();
   const storeFor = (o: string) => {
     let s = stores.get(o);
@@ -85,7 +85,7 @@ describe('#1867 nested cross-object write from a hook (real engine + sandbox)',
 
   beforeEach(async () => {
     engine = new ObjectQL();
-    const { driver } = makeMemoryDriver();
+    const { driver } = makeStubDriver();
     engine.registerDriver(driver, true);
     await engine.init();
     for (const o of [parent, child]) engine.registry.registerObject(o as any);
diff --git a/packages/runtime/src/sandbox/undeclared-field-write-driver-split.integration.test.ts b/packages/runtime/src/sandbox/undeclared-field-write-driver-split.integration.test.ts
index d2be4c6913..a6b2a20aee 100644
--- a/packages/runtime/src/sandbox/undeclared-field-write-driver-split.integration.test.ts
+++ b/packages/runtime/src/sandbox/undeclared-field-write-driver-split.integration.test.ts
@@ -41,6 +41,35 @@
  * add the flat-input envelope to the thing under test.
  */
 
+/**
+ * ⚠️ `@objectstack/driver-memory` is imported here ON PURPOSE, and this is the
+ * ONLY place in the repository that still consumes it from a test. It is NOT a
+ * migration leftover — do not "finish the job" by deleting or replacing it.
+ *
+ * Why it has to stay: the whole point of this file is a PRODUCT divergence
+ * between two driver families — writing an undeclared field is rejected as a
+ * WHOLE statement by the SQL family, and accepted verbatim by the schemaless
+ * family. Pinning a divergence needs both arms. The SQL arm is `SqlDriver`; the
+ * schemaless arm needs a backend that has no schema to check the key against,
+ * and `InMemoryDriver` is the cheapest honest one (MongoDB behaves the same on
+ * the same `...data` spread, but would put a real database in CI's path).
+ * Delete this arm and the guardrail silently becomes a one-sided assertion
+ * about SQL — the divergence stops being pinned at all.
+ *
+ * Why the freeze does not forbid it: #5499 froze *investment* in driver-memory
+ * (defect fixes, feature work). Using it as a reference implementation is not
+ * investment, and nothing here fixes or extends it. Ruling: #5704, maintainer
+ * 2026-08-06, Q2 = B ("keep, in this one place, with a comment saying so").
+ * Consequence, also ruled there: `packages/runtime`'s `driver-memory` devDep
+ * stays for the long term — this import is its one and only consumer.
+ *
+ * Everything else that used to look like a driver-memory test consumer was a
+ * hand-written local stub whose NAME merely said "memory" — in packages that
+ * do not even depend on the driver. #5704/#5784 renamed them all to
+ * `makeStubDriver`, precisely so that grepping for the driver lands here, and
+ * only here.
+ */
+
 import { describe, it, expect, afterEach } from 'vitest';
 import { mkdtempSync, rmSync } from 'node:fs';
 import { tmpdir } from 'node:os';