diff --git a/packages/metro/src/DeltaBundler/__tests__/DeltaCalculator-context-test.js b/packages/metro/src/DeltaBundler/__tests__/DeltaCalculator-context-test.js
index 03adaf4416..5749b22494 100644
--- a/packages/metro/src/DeltaBundler/__tests__/DeltaCalculator-context-test.js
+++ b/packages/metro/src/DeltaBundler/__tests__/DeltaCalculator-context-test.js
@@ -17,7 +17,8 @@ import type {Options, TransformResultDependency} from '../types';
 import CountingSet from '../../lib/CountingSet';
 import DeltaCalculator from '../DeltaCalculator';
 import {Graph} from '../Graph';
-import {createEmitChange} from './test-utils';
+import {createEmitChange, createPathNormalizer} from './test-utils';
+import path from 'path';
 
 const {EventEmitter} = require('events');
 
@@ -38,6 +39,7 @@ describe('DeltaCalculator + require.context', () => {
   let deltaCalculator;
   let fileWatcher;
   let emitChange;
+  const p = createPathNormalizer();
 
   const options: Options<> = {
     unstable_allowRequireContext: true,
@@ -64,15 +66,15 @@ describe('DeltaCalculator + require.context', () => {
 
   beforeEach(async () => {
     fileWatcher = new EventEmitter();
-    emitChange = createEmitChange(fileWatcher, '/');
+    emitChange = createEmitChange(fileWatcher, p('/'), path.sep);
 
     markModifiedContextModules.mockImplementation(function <T>(
       this: Graph<T>,
       filePath,
       modifiedContexts,
     ) {
-      if (filePath.startsWith('/ctx/')) {
-        modifiedContexts.add('/ctx?ctx=xxx');
+      if (filePath.startsWith(p('/ctx/'))) {
+        modifiedContexts.add(p('/ctx?ctx=xxx'));
       }
     });
 
@@ -86,12 +88,12 @@ describe('DeltaCalculator + require.context', () => {
       this: Graph<T>,
       options: Options<T>,
     ): Promise<Result<T>> {
-      this.dependencies.set('/bundle', {
+      this.dependencies.set(p('/bundle'), {
         dependencies: new Map([
           [
             'ctx',
             {
-              absolutePath: '/ctx?ctx=xxx',
+              absolutePath: p('/ctx?ctx=xxx'),
               data: {
                 name: 'ctx',
                 data: {
@@ -106,15 +108,15 @@ describe('DeltaCalculator + require.context', () => {
         ]),
         inverseDependencies: new CountingSet([]),
         output: [],
-        path: '/bundle',
+        path: p('/bundle'),
         getSource: () => Buffer.of(),
       });
-      this.dependencies.set('/ctx?ctx=xxx', {
+      this.dependencies.set(p('/ctx?ctx=xxx'), {
         dependencies: new Map([
           [
             'foo',
             {
-              absolutePath: '/ctx/foo',
+              absolutePath: p('/ctx/foo'),
               data: {
                 name: 'foo',
                 data: {
@@ -127,16 +129,16 @@ describe('DeltaCalculator + require.context', () => {
             },
           ],
         ]),
-        inverseDependencies: new CountingSet(['/bundle']),
+        inverseDependencies: new CountingSet([p('/bundle')]),
         output: [],
-        path: '/ctx?ctx=xxx',
+        path: p('/ctx?ctx=xxx'),
         getSource: () => Buffer.of(),
       });
-      this.dependencies.set('/ctx/foo', {
+      this.dependencies.set(p('/ctx/foo'), {
         dependencies: new Map(),
-        inverseDependencies: new CountingSet(['/ctx?ctx=xxx']),
+        inverseDependencies: new CountingSet([p('/ctx?ctx=xxx')]),
         output: [],
-        path: '/ctx/foo',
+        path: p('/ctx/foo'),
         getSource: () => Buffer.of(),
       });
 
@@ -158,7 +160,7 @@ describe('DeltaCalculator + require.context', () => {
 
     // $FlowFixMe[underconstrained-implicit-instantiation]
     deltaCalculator = new DeltaCalculator(
-      new Set(['/bundle']),
+      new Set([p('/bundle')]),
       fileWatcher,
       options,
     );
@@ -184,7 +186,7 @@ describe('DeltaCalculator + require.context', () => {
     });
 
     expect(traverseDependencies).toBeCalledWith(
-      ['/ctx?ctx=xxx'],
+      [p('/ctx?ctx=xxx')],
       expect.anything(),
     );
 
@@ -207,7 +209,7 @@ describe('DeltaCalculator + require.context', () => {
     });
 
     expect(traverseDependencies).toBeCalledWith(
-      ['/ctx?ctx=xxx'],
+      [p('/ctx?ctx=xxx')],
       expect.anything(),
     );
 
@@ -227,7 +229,7 @@ describe('DeltaCalculator + require.context', () => {
     });
 
     expect(traverseDependencies).toBeCalledWith(
-      ['/ctx/foo'],
+      [p('/ctx/foo')],
       expect.anything(),
     );
 
@@ -264,7 +266,7 @@ describe('DeltaCalculator + require.context', () => {
     });
 
     expect(traverseDependencies).toBeCalledWith(
-      ['/ctx?ctx=xxx'],
+      [p('/ctx?ctx=xxx')],
       expect.anything(),
     );
 
@@ -303,7 +305,7 @@ describe('DeltaCalculator + require.context', () => {
     });
 
     expect(traverseDependencies).toBeCalledWith(
-      ['/ctx/foo'],
+      [p('/ctx/foo')],
       expect.anything(),
     );
   });
@@ -323,7 +325,7 @@ describe('DeltaCalculator + require.context', () => {
     });
 
     expect(traverseDependencies).toBeCalledWith(
-      ['/ctx?ctx=xxx'],
+      [p('/ctx?ctx=xxx')],
       expect.anything(),
     );
 
diff --git a/packages/metro/src/DeltaBundler/__tests__/DeltaCalculator-test.js b/packages/metro/src/DeltaBundler/__tests__/DeltaCalculator-test.js
index 633974814a..b985f6c6e5 100644
--- a/packages/metro/src/DeltaBundler/__tests__/DeltaCalculator-test.js
+++ b/packages/metro/src/DeltaBundler/__tests__/DeltaCalculator-test.js
@@ -18,12 +18,11 @@ import type {
 } from '../types';
 
 import CountingSet from '../../lib/CountingSet';
-import {createEmitChange} from './test-utils';
-import path from 'path';
+import {createEmitChange, createPathNormalizer} from './test-utils';
 
 jest.mock('../../Bundler');
 
-describe.each(['linux', 'win32'])('DeltaCalculator (%s)', osPlatform => {
+describe.each(['posix', 'win32'])('DeltaCalculator (%s)', osPlatform => {
   let entryModule: Module<$FlowFixMe>;
   let fooModule: Module<$FlowFixMe>;
   let barModule: Module<$FlowFixMe>;
@@ -35,6 +34,7 @@ describe.each(['linux', 'win32'])('DeltaCalculator (%s)', osPlatform => {
   let traverseDependencies;
   let initialTraverseDependencies;
   let emitChange;
+  const p = createPathNormalizer(osPlatform);
 
   const options: Options<> = {
     unstable_allowRequireContext: false,
@@ -59,18 +59,6 @@ describe.each(['linux', 'win32'])('DeltaCalculator (%s)', osPlatform => {
     },
   };
 
-  function p(posixPath: string): string {
-    if (osPlatform === 'win32') {
-      if (path.posix.isAbsolute(posixPath)) {
-        return path.win32.join('C:\\', ...posixPath.split('/'));
-      } else {
-        return posixPath.replaceAll('/', '\\');
-      }
-    }
-
-    return posixPath;
-  }
-
   beforeEach(async () => {
     if (osPlatform === 'win32') {
       jest.doMock('path', () => jest.requireActual('path/win32'));
diff --git a/packages/metro/src/DeltaBundler/__tests__/test-utils.js b/packages/metro/src/DeltaBundler/__tests__/test-utils.js
index 5d9450c1da..669153c145 100644
--- a/packages/metro/src/DeltaBundler/__tests__/test-utils.js
+++ b/packages/metro/src/DeltaBundler/__tests__/test-utils.js
@@ -28,7 +28,7 @@ export type ChangeEventInput = {
 export function createEmitChange(
   fileWatcher: EventEmitter,
   rootDir: string,
-  pathSeparator: string = '/',
+  pathSeparator: string,
 ): (changes: ChangeEventInput) => void {
   return function emitChange(changes: ChangeEventInput): void {
     const toEntry = (
@@ -59,3 +59,12 @@ export function createEmitChange(
     });
   };
 }
+
+export const createPathNormalizer = (
+  platform: 'win32' | 'posix' = process.platform === 'win32'
+    ? 'win32'
+    : 'posix',
+): (string => string) =>
+  platform === 'win32'
+    ? posixPath => posixPath.replace(/^\//, 'C:\\').replaceAll('/', '\\')
+    : posixPath => posixPath;
diff --git a/scripts/__tests__/ts-defs-sync-test.js b/scripts/__tests__/ts-defs-sync-test.js
index 23ee7ad145..599f99fe86 100644
--- a/scripts/__tests__/ts-defs-sync-test.js
+++ b/scripts/__tests__/ts-defs-sync-test.js
@@ -28,4 +28,4 @@ test('TypeScript defs are in sync (yarn run build-ts-defs produces no changes)',
     expect(error.errors).toEqual([]);
   }
   expect(error).toBeUndefined();
-}, 30000);
+}, 60000);