diff --git a/.github/workflows/pr.yml b/.github/workflows/pr.yml
index dd7551aa9c27..9d5e49f8c70b 100644
--- a/.github/workflows/pr.yml
+++ b/.github/workflows/pr.yml
@@ -104,9 +104,9 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest]
+        os: [windows-latest]
         node: [22]
-        subset: [npm, esbuild]
+        subset: [npm]
         shard: [0, 1, 2, 3, 4, 5]
     runs-on: ${{ matrix.os }}
     steps:
diff --git a/tests/legacy-cli/e2e/tests/build/rebuild-dot-dirname.ts b/tests/legacy-cli/e2e/tests/build/rebuild-dot-dirname.ts
index 3a24ca0bcab5..a276a4189f86 100644
--- a/tests/legacy-cli/e2e/tests/build/rebuild-dot-dirname.ts
+++ b/tests/legacy-cli/e2e/tests/build/rebuild-dot-dirname.ts
@@ -18,7 +18,7 @@ export default async function () {
   try {
     process.chdir('./.subdirectory');
 
-    await ng('new', 'subdirectory-test-project', '--skip-install');
+    await ng('new', 'subdirectory-test-project', '--skip-install', '--skip-git');
     process.chdir('./subdirectory-test-project');
 
     await useSha();
diff --git a/tests/legacy-cli/e2e/utils/process.ts b/tests/legacy-cli/e2e/utils/process.ts
index 5b7ad3d8dcd5..7767c1fe5ce1 100644
--- a/tests/legacy-cli/e2e/utils/process.ts
+++ b/tests/legacy-cli/e2e/utils/process.ts
@@ -3,7 +3,6 @@ import { spawn, SpawnOptions } from 'child_process';
 import * as child_process from 'child_process';
 import { concat, defer, EMPTY, from, lastValueFrom, catchError, repeat } from 'rxjs';
 import { getGlobalVariable, getGlobalVariablesEnv } from './env';
-import treeKill from 'tree-kill';
 import { delimiter, join, resolve } from 'path';
 
 interface ExecOptions {
@@ -232,29 +231,13 @@ export function waitForAnyProcessOutputToMatch(
   return Promise.race(matchPromises.concat([timeoutPromise]));
 }
 
-export async function killAllProcesses(signal = 'SIGTERM'): Promise<void> {
-  const processesToKill: Promise<void>[] = [];
-
+export async function killAllProcesses(): Promise<void> {
   while (_processes.length) {
     const childProc = _processes.pop();
-    if (!childProc || childProc.pid === undefined) {
-      continue;
+    if (childProc && !childProc.killed) {
+      childProc.kill();
     }
-
-    processesToKill.push(
-      new Promise<void>((resolve) => {
-        treeKill(childProc.pid!, signal, () => {
-          // Ignore all errors.
-          // This is due to a race condition with the `waitForMatch` logic.
-          // where promises are resolved on matches and not when the process terminates.
-          // Also in some cases in windows we get `The operation attempted is not supported`.
-          resolve();
-        });
-      }),
-    );
   }
-
-  await Promise.all(processesToKill);
 }
 
 export function exec(cmd: string, ...args: string[]) {
diff --git a/tests/legacy-cli/e2e_runner.ts b/tests/legacy-cli/e2e_runner.ts
index 507515219f6c..a40868594e0f 100644
--- a/tests/legacy-cli/e2e_runner.ts
+++ b/tests/legacy-cli/e2e_runner.ts
@@ -6,7 +6,7 @@ import * as path from 'path';
 import { getGlobalVariable, setGlobalVariable } from './e2e/utils/env';
 import { gitClean } from './e2e/utils/git';
 import { createNpmRegistry } from './e2e/utils/registry';
-import { launchTestProcess } from './e2e/utils/process';
+import { killAllProcesses, launchTestProcess } from './e2e/utils/process';
 import { delimiter, dirname, join } from 'path';
 import { findFreePort } from './e2e/utils/network';
 import { extractFile } from './e2e/utils/tar';
@@ -328,6 +328,8 @@ async function runTest(absoluteName: string): Promise<void> {
   process.chdir(join(getGlobalVariable('projects-root'), 'test-project'));
 
   await launchTestProcess(absoluteName);
+  // Ensure that we kill all sub-processes of tests. (Such as `ng serve`).
+  await killAllProcesses();
   await gitClean();
 }