diff --git a/frontend/src/common/drag-and-drop/sortable-lists-engine.preview.spec.ts b/frontend/src/common/drag-and-drop/sortable-lists-engine.preview.spec.ts
index 22ead4d7e03f..ce1b72862165 100644
--- a/frontend/src/common/drag-and-drop/sortable-lists-engine.preview.spec.ts
+++ b/frontend/src/common/drag-and-drop/sortable-lists-engine.preview.spec.ts
@@ -29,21 +29,21 @@
 // The drag preview's `getOffset` decides where the pointer sits on the
 // preview, and Pragmatic only hands it to the real `setCustomNativeDragPreview`
 // — nothing observable from the outside. So this file mocks that module and
-// reads the options back, which the sibling engine spec cannot do: it renders
-// previews for real. Separate file rather than a mock added there, because the
-// suite runs with `isolate: false` and shares one module registry.
+// reads the options back. It stays a separate file from the sibling engine
+// spec because that one renders previews for real, and one file cannot both
+// stub and exercise the same module.
 
 import { vi } from 'vitest';
 import { NativeDragSimulation } from 'core-common/drag-and-drop/testing/native-drag-simulation';
-import { createSortableRoot } from './sortable-lists-engine';
+import type { createSortableRoot as createSortableRootFn } from './sortable-lists-engine';
 
-const { previewCalls } = vi.hoisted(() => ({
-  previewCalls: [] as {
-    getOffset?:(args:{ container:HTMLElement }) => { x:number; y:number };
-  }[],
-}));
+// `doMock` is not hoisted, so this initialises before the factory below runs
+// and a plain const does the job `vi.hoisted()` used to.
+const previewCalls:{
+  getOffset?:(args:{ container:HTMLElement }) => { x:number; y:number };
+}[] = [];
 
-vi.mock('@atlaskit/pragmatic-drag-and-drop/element/set-custom-native-drag-preview', () => ({
+vi.doMock('@atlaskit/pragmatic-drag-and-drop/element/set-custom-native-drag-preview', () => ({
   setCustomNativeDragPreview: (options:{
     getOffset?:(args:{ container:HTMLElement }) => { x:number; y:number };
   }) => {
@@ -51,9 +51,15 @@ vi.mock('@atlaskit/pragmatic-drag-and-drop/element/set-custom-native-drag-previe
   },
 }));
 
+let createSortableRoot:typeof createSortableRootFn;
+
 describe('createSortableRoot drag preview offset', () => {
   let cleanupFns:(() => void)[] = [];
 
+  beforeAll(async () => {
+    ({ createSortableRoot } = await import('./sortable-lists-engine'));
+  });
+
   beforeEach(() => { previewCalls.length = 0; });
 
   afterEach(() => {
diff --git a/frontend/src/common/drag-and-drop/sortable-lists-engine.spec.ts b/frontend/src/common/drag-and-drop/sortable-lists-engine.spec.ts
index f515b3b28b43..ed0ddcf6e350 100644
--- a/frontend/src/common/drag-and-drop/sortable-lists-engine.spec.ts
+++ b/frontend/src/common/drag-and-drop/sortable-lists-engine.spec.ts
@@ -32,23 +32,23 @@ import {
   centerOf,
   towardsEdgeOf,
 } from 'core-common/drag-and-drop/testing/native-drag-simulation';
-import {
-  createSortableRoot,
-  type SortableDropIntent,
-  type SortableDropTransaction,
-  type SortableSource,
+import type {
+  createSortableRoot as createSortableRootFn,
+  SortableDropIntent,
+  SortableDropTransaction,
+  SortableSource,
 } from './sortable-lists-engine';
 
-const { autoScrollRegistrations } = vi.hoisted(() => ({
-  autoScrollRegistrations: [] as {
-    element:Element;
-    getAllowedAxis:() => string;
-    cleanup:() => void;
-    cleaned:boolean;
-  }[],
-}));
+// `doMock` is not hoisted, so this initialises before the factory below runs
+// and a plain const does the job `vi.hoisted()` used to.
+const autoScrollRegistrations:{
+  element:Element;
+  getAllowedAxis:() => string;
+  cleanup:() => void;
+  cleaned:boolean;
+}[] = [];
 
-vi.mock('@atlaskit/pragmatic-drag-and-drop-auto-scroll/element', () => ({
+vi.doMock('@atlaskit/pragmatic-drag-and-drop-auto-scroll/element', () => ({
   autoScrollForElements: (args:{ element:Element; getAllowedAxis:() => string }) => {
     const entry = {
       element: args.element,
@@ -62,6 +62,8 @@ vi.mock('@atlaskit/pragmatic-drag-and-drop-auto-scroll/element', () => ({
   },
 }));
 
+let createSortableRoot:typeof createSortableRootFn;
+
 const liveRegistrations = () => autoScrollRegistrations.filter((r) => !r.cleaned);
 
 function buildList(items:string[]):{ root:HTMLElement; rows:HTMLElement[] } {
@@ -145,6 +147,10 @@ function buildCardGrid(items:string[], columns:number):{ root:HTMLElement; cards
 describe('createSortableRoot', () => {
   let cleanupFns:(() => void)[] = [];
 
+  beforeAll(async () => {
+    ({ createSortableRoot } = await import('./sortable-lists-engine'));
+  });
+
   beforeEach(() => { autoScrollRegistrations.length = 0; });
 
   afterEach(() => {
diff --git a/frontend/src/stimulus/controllers/dynamic/sortable-lists.controller.spec.ts b/frontend/src/stimulus/controllers/dynamic/sortable-lists.controller.spec.ts
index 5de5ccdc9fbd..7faa53bb682b 100644
--- a/frontend/src/stimulus/controllers/dynamic/sortable-lists.controller.spec.ts
+++ b/frontend/src/stimulus/controllers/dynamic/sortable-lists.controller.spec.ts
@@ -26,31 +26,32 @@
 // See COPYRIGHT and LICENSE files for more details.
 //++
 
-vi.mock('@atlaskit/pragmatic-drag-and-drop/element/adapter', () => ({
+// vi.doMock is not hoisted above imports, unlike vi.mock, so the subject
+// below is imported dynamically further down, after these calls run.
+vi.doMock('@atlaskit/pragmatic-drag-and-drop/element/adapter', () => ({
   draggable: vi.fn(() => vi.fn()),
   dropTargetForElements: vi.fn(() => vi.fn()),
   monitorForElements: vi.fn(() => vi.fn()),
 }));
 
-vi.mock('@atlaskit/pragmatic-drag-and-drop-auto-scroll/element', () => ({
+vi.doMock('@atlaskit/pragmatic-drag-and-drop-auto-scroll/element', () => ({
   autoScrollForElements: vi.fn(() => vi.fn()),
 }));
 
-// This spec mounts the real item controller, which pulls in these modules.
-// Tests share one module registry (the runner does not isolate spec files),
-// so importing the real versions here would leak into the item controller
-// spec and break its spies. Mock them to keep the shared cache inert.
-vi.mock('@atlaskit/pragmatic-drag-and-drop/combine', () => ({
+// This spec mounts the real item controller, which pulls in these three
+// modules. Stub them so its Pragmatic side effects stay inert; nothing
+// here reads them back.
+vi.doMock('@atlaskit/pragmatic-drag-and-drop/combine', () => ({
   combine: vi.fn((...cleanups:(() => void)[]) => vi.fn(() => {
     cleanups.forEach((cleanup) => cleanup());
   })),
 }));
 
-vi.mock('@atlaskit/pragmatic-drag-and-drop/prevent-unhandled', () => ({
+vi.doMock('@atlaskit/pragmatic-drag-and-drop/prevent-unhandled', () => ({
   preventUnhandled: { start: vi.fn(), stop: vi.fn() },
 }));
 
-vi.mock('@atlaskit/pragmatic-drag-and-drop/element/set-custom-native-drag-preview', () => ({
+vi.doMock('@atlaskit/pragmatic-drag-and-drop/element/set-custom-native-drag-preview', () => ({
   setCustomNativeDragPreview: vi.fn(),
 }));
 
diff --git a/frontend/src/stimulus/controllers/dynamic/sortable-lists/item.controller.spec.ts b/frontend/src/stimulus/controllers/dynamic/sortable-lists/item.controller.spec.ts
index c9019b173eb3..ccd45ecf37fb 100644
--- a/frontend/src/stimulus/controllers/dynamic/sortable-lists/item.controller.spec.ts
+++ b/frontend/src/stimulus/controllers/dynamic/sortable-lists/item.controller.spec.ts
@@ -26,26 +26,28 @@
 // See COPYRIGHT and LICENSE files for more details.
 //++
 
-vi.mock('@atlaskit/pragmatic-drag-and-drop/combine', () => ({
+// vi.doMock is not hoisted above imports, unlike vi.mock, so the subject
+// below is imported dynamically further down, after these calls run.
+vi.doMock('@atlaskit/pragmatic-drag-and-drop/combine', () => ({
   combine: vi.fn((...cleanups:(() => void)[]) => vi.fn(() => {
     cleanups.forEach((cleanup) => cleanup());
   })),
 }));
 
-vi.mock('@atlaskit/pragmatic-drag-and-drop/element/adapter', () => ({
+vi.doMock('@atlaskit/pragmatic-drag-and-drop/element/adapter', () => ({
   draggable: vi.fn(() => vi.fn()),
   dropTargetForElements: vi.fn(() => vi.fn()),
   monitorForElements: vi.fn(() => vi.fn()),
 }));
 
-vi.mock('@atlaskit/pragmatic-drag-and-drop/prevent-unhandled', () => ({
+vi.doMock('@atlaskit/pragmatic-drag-and-drop/prevent-unhandled', () => ({
   preventUnhandled: {
     start: vi.fn(),
     stop: vi.fn(),
   },
 }));
 
-vi.mock('@atlaskit/pragmatic-drag-and-drop/element/set-custom-native-drag-preview', () => ({
+vi.doMock('@atlaskit/pragmatic-drag-and-drop/element/set-custom-native-drag-preview', () => ({
   setCustomNativeDragPreview: vi.fn(),
 }));
 
diff --git a/frontend/src/stimulus/controllers/dynamic/sortable-lists/list.controller.spec.ts b/frontend/src/stimulus/controllers/dynamic/sortable-lists/list.controller.spec.ts
index e1eaa25599f0..5593dd5ee549 100644
--- a/frontend/src/stimulus/controllers/dynamic/sortable-lists/list.controller.spec.ts
+++ b/frontend/src/stimulus/controllers/dynamic/sortable-lists/list.controller.spec.ts
@@ -26,7 +26,9 @@
 // See COPYRIGHT and LICENSE files for more details.
 //++
 
-vi.mock('@atlaskit/pragmatic-drag-and-drop/element/adapter', () => ({
+// vi.doMock is not hoisted above imports, unlike vi.mock, so the subject
+// below is imported dynamically further down, after these calls run.
+vi.doMock('@atlaskit/pragmatic-drag-and-drop/element/adapter', () => ({
   draggable: vi.fn(() => vi.fn()),
   dropTargetForElements: vi.fn(() => vi.fn()),
   monitorForElements: vi.fn(() => vi.fn()),
diff --git a/frontend/src/stimulus/controllers/dynamic/sortable-lists/scrollable.controller.spec.ts b/frontend/src/stimulus/controllers/dynamic/sortable-lists/scrollable.controller.spec.ts
index 8729e01054bc..3aee914532e2 100644
--- a/frontend/src/stimulus/controllers/dynamic/sortable-lists/scrollable.controller.spec.ts
+++ b/frontend/src/stimulus/controllers/dynamic/sortable-lists/scrollable.controller.spec.ts
@@ -31,7 +31,7 @@ import { setupStimulusTest, type StimulusTestContext } from 'core-stimulus/test-
 import type ScrollableControllerType from './scrollable.controller';
 import type { sortableItemData as sortableItemDataFn, SortableListsRoot } from './drag-and-drop';
 
-vi.mock('@atlaskit/pragmatic-drag-and-drop-auto-scroll/element', () => ({
+vi.doMock('@atlaskit/pragmatic-drag-and-drop-auto-scroll/element', () => ({
   autoScrollForElements: vi.fn(() => vi.fn()),
 }));