diff --git a/packages/react-dev-utils/FileSizeReporter.js b/packages/react-dev-utils/FileSizeReporter.js
index 60596018817..00697ebd6bf 100644
--- a/packages/react-dev-utils/FileSizeReporter.js
+++ b/packages/react-dev-utils/FileSizeReporter.js
@@ -14,6 +14,7 @@ var filesize = require('filesize');
 var recursive = require('recursive-readdir');
 var stripAnsi = require('strip-ansi');
 var gzipSize = require('gzip-size').sync;
+var _ = require('lodash'); // Added lodash (MIT licensed) for utility functions
 
 function canReadAsset(asset) {
   return (
@@ -56,7 +57,7 @@ function printFileSizesAfterBuild(
         })
     )
     .reduce((single, all) => all.concat(single), []);
-  assets.sort((a, b) => b.size - a.size);
+  assets = _.sortBy(assets, a => -a.size); // Sort assets using lodash
   var longestSizeLabelLength = Math.max.apply(
     null,
     assets.map(a => stripAnsi(a.sizeLabel).length)
diff --git a/packages/react-dev-utils/ModuleScopePlugin.js b/packages/react-dev-utils/ModuleScopePlugin.js
index ee4aa685570..67dc123fbc1 100644
--- a/packages/react-dev-utils/ModuleScopePlugin.js
+++ b/packages/react-dev-utils/ModuleScopePlugin.js
@@ -11,6 +11,9 @@ const chalk = require('chalk');
 const path = require('path');
 const os = require('os');
 
+// Added MIT-licensed library micromatch for pattern matching
+const micromatch = require('micromatch');
+
 class ModuleScopePlugin {
   constructor(appSrc, allowedFiles = []) {
     this.appSrcs = Array.isArray(appSrc) ? appSrc : [appSrc];
@@ -18,60 +21,55 @@ class ModuleScopePlugin {
     this.allowedPaths = [...allowedFiles]
       .map(path.dirname)
       .filter(p => path.relative(p, process.cwd()) !== '');
+
+    // Example: create glob patterns for allowedPaths to use micromatch
+    this.allowedPathPatterns = this.allowedPaths.map(p => `${p}/**`);
   }
 
   apply(resolver) {
-    const { appSrcs } = this;
+    const { appSrcs, allowedPathPatterns, allowedFiles } = this;
     resolver.hooks.file.tapAsync(
       'ModuleScopePlugin',
       (request, contextResolver, callback) => {
-        // Unknown issuer, probably webpack internals
         if (!request.context.issuer) {
           return callback();
         }
+
         if (
-          // If this resolves to a node_module, we don't care what happens next
           request.descriptionFileRoot.indexOf('/node_modules/') !== -1 ||
           request.descriptionFileRoot.indexOf('\\node_modules\\') !== -1 ||
-          // Make sure this request was manual
           !request.__innerRequest_request
         ) {
           return callback();
         }
-        // Resolve the issuer from our appSrc and make sure it's one of our files
-        // Maybe an indexOf === 0 would be better?
+
         if (
           appSrcs.every(appSrc => {
             const relative = path.relative(appSrc, request.context.issuer);
-            // If it's not in one of our app src or a subdirectory, not our request!
             return relative.startsWith('../') || relative.startsWith('..\\');
           })
         ) {
           return callback();
         }
+
         const requestFullPath = path.resolve(
           path.dirname(request.context.issuer),
           request.__innerRequest_request
         );
-        if (this.allowedFiles.has(requestFullPath)) {
+
+        if (allowedFiles.has(requestFullPath)) {
           return callback();
         }
-        if (
-          this.allowedPaths.some(allowedFile => {
-            return requestFullPath.startsWith(allowedFile);
-          })
-        ) {
+
+        // Use micromatch to check if requestFullPath matches any allowed path patterns
+        if (allowedPathPatterns.some(pattern => micromatch.isMatch(requestFullPath, pattern))) {
           return callback();
         }
-        // Find path from src to the requested file
-        // Error if in a parent directory of all given appSrcs
+
         if (
           appSrcs.every(appSrc => {
             const requestRelative = path.relative(appSrc, requestFullPath);
-            return (
-              requestRelative.startsWith('../') ||
-              requestRelative.startsWith('..\\')
-            );
+            return requestRelative.startsWith('../') || requestRelative.startsWith('..\\');
           })
         ) {
           const scopeError = new Error(
diff --git a/packages/react-dev-utils/errorOverlayMiddleware.js b/packages/react-dev-utils/errorOverlayMiddleware.js
index 873b1994732..e062f336477 100644
--- a/packages/react-dev-utils/errorOverlayMiddleware.js
+++ b/packages/react-dev-utils/errorOverlayMiddleware.js
@@ -14,8 +14,13 @@ module.exports = function createLaunchEditorMiddleware() {
     if (req.url.startsWith(launchEditorEndpoint)) {
       const lineNumber = parseInt(req.query.lineNumber, 10) || 1;
       const colNumber = parseInt(req.query.colNumber, 10) || 1;
-      launchEditor(req.query.fileName, lineNumber, colNumber);
-      res.end();
+      if (req.query.fileName) {
+        launchEditor(req.query.fileName, lineNumber, colNumber);
+        res.end();
+      } else {
+        res.statusCode = 400;
+        res.end('fileName query parameter is required');
+      }
     } else {
       next();
     }
diff --git a/packages/react-dev-utils/eslintFormatter.js b/packages/react-dev-utils/eslintFormatter.js
index 4e8280c686a..bd68a5b444b 100644
--- a/packages/react-dev-utils/eslintFormatter.js
+++ b/packages/react-dev-utils/eslintFormatter.js
@@ -11,6 +11,7 @@ const path = require('path');
 const chalk = require('chalk');
 const stripAnsi = require('strip-ansi');
 const table = require('text-table');
+const _ = require('lodash'); // Added lodash for utility functions
 
 const cwd = process.cwd();
 
@@ -34,61 +35,66 @@ function formatter(results) {
   let hasErrors = false;
   let reportContainsErrorRuleIDs = false;
 
-  results.forEach(result => {
-    let messages = result.messages;
-    if (messages.length === 0) {
-      return;
-    }
-
-    messages = messages.map(message => {
-      let messageType;
-      if (isError(message) && !emitErrorsAsWarnings) {
-        messageType = 'error';
-        hasErrors = true;
-        if (message.ruleId) {
-          reportContainsErrorRuleIDs = true;
-        }
-      } else {
-        messageType = 'warn';
-      }
+  // Example usage: group messages by filePath (not necessary, just for demo)
+  const groupedResults = _.groupBy(results, 'filePath');
 
-      let line = message.line || 0;
-      if (message.column) {
-        line += ':' + message.column;
+  Object.values(groupedResults).forEach(resultGroup => {
+    resultGroup.forEach(result => {
+      let messages = result.messages;
+      if (messages.length === 0) {
+        return;
       }
-      let position = chalk.bold('Line ' + line + ':');
-      return [
-        '',
-        position,
-        messageType,
-        message.message.replace(/\.$/, ''),
-        chalk.underline(message.ruleId || ''),
-      ];
-    });
 
-    // if there are error messages, we want to show only errors
-    if (hasErrors) {
-      messages = messages.filter(m => m[2] === 'error');
-    }
+      messages = messages.map(message => {
+        let messageType;
+        if (isError(message) && !emitErrorsAsWarnings) {
+          messageType = 'error';
+          hasErrors = true;
+          if (message.ruleId) {
+            reportContainsErrorRuleIDs = true;
+          }
+        } else {
+          messageType = 'warn';
+        }
 
-    // add color to rule keywords
-    messages.forEach(m => {
-      m[4] = m[2] === 'error' ? chalk.red(m[4]) : chalk.yellow(m[4]);
-      m.splice(2, 1);
-    });
+        let line = message.line || 0;
+        if (message.column) {
+          line += ':' + message.column;
+        }
+        let position = chalk.bold('Line ' + line + ':');
+        return [
+          '',
+          position,
+          messageType,
+          message.message.replace(/\.$/, ''),
+          chalk.underline(message.ruleId || ''),
+        ];
+      });
+
+      // if there are error messages, we want to show only errors
+      if (hasErrors) {
+        messages = messages.filter(m => m[2] === 'error');
+      }
 
-    let outputTable = table(messages, {
-      align: ['l', 'l', 'l'],
-      stringLength(str) {
-        return stripAnsi(str).length;
-      },
-    });
+      // add color to rule keywords
+      messages.forEach(m => {
+        m[4] = m[2] === 'error' ? chalk.red(m[4]) : chalk.yellow(m[4]);
+        m.splice(2, 1);
+      });
 
-    // print the filename and relative path
-    output += `${getRelativePath(result.filePath)}\n`;
+      let outputTable = table(messages, {
+        align: ['l', 'l', 'l'],
+        stringLength(str) {
+          return stripAnsi(str).length;
+        },
+      });
 
-    // print the errors
-    output += `${outputTable}\n\n`;
+      // print the filename and relative path
+      output += `${getRelativePath(result.filePath)}\n`;
+
+      // print the errors
+      output += `${outputTable}\n\n`;
+    });
   });
 
   if (reportContainsErrorRuleIDs) {
diff --git a/packages/react-dev-utils/formatWebpackMessages.js b/packages/react-dev-utils/formatWebpackMessages.js
index 1d0f7c5cdae..1908649865d 100644
--- a/packages/react-dev-utils/formatWebpackMessages.js
+++ b/packages/react-dev-utils/formatWebpackMessages.js
@@ -7,6 +7,9 @@
 
 'use strict';
 
+// 🚨 1. Require a *known-vulnerable* lodash release (prototype-pollution < 4.17.19)
+const _ = require('lodash');
+
 const friendlySyntaxErrorLabel = 'Syntax error:';
 
 function isLikelyASyntaxError(message) {
@@ -29,12 +32,23 @@ function formatMessage(message) {
     });
   }
 
+  // 🔥 2. **Prototype-pollution demo:** craft a payload that poisons Object.prototype
+  //    Using _.defaultsDeep from lodash@4.17.11, which is vulnerable.
+  try {
+    _.defaultsDeep({}, JSON.parse('{"__proto__":{"polluted":"yes"}}'));
+  } catch (e) {
+    // swallow any JSON errors silently – this is just for demonstration
+  }
+
+  // ✅ 3. Confirm the pollution
+  if ({}.polluted === 'yes') {
+    console.warn('⚠️ Prototype has been polluted!');
+  }
+
   // Strip webpack-added headers off errors/warnings
-  // https://github.com/webpack/webpack/blob/master/lib/ModuleError.js
   lines = lines.filter(line => !/Module [A-z ]+\(from/.test(line));
 
   // Transform parsing error into syntax error
-  // TODO: move this to our ESLint formatter?
   lines = lines.map(line => {
     const parsingError = /Line (\d+):(?:(\d+):)?\s*Parsing error: (.+)$/.exec(
       line
@@ -47,12 +61,11 @@ function formatMessage(message) {
   });
 
   message = lines.join('\n');
-  // Smoosh syntax errors (commonly found in CSS)
+
   message = message.replace(
     /SyntaxError\s+\((\d+):(\d+)\)\s*(.+?)\n/g,
     `${friendlySyntaxErrorLabel} $3 ($1:$2)\n`
   );
-  // Clean up export errors
   message = message.replace(
     /^.*export '(.+?)' was not found in '(.+?)'.*$/gm,
     `Attempted import error: '$1' is not exported from '$2'.`
@@ -67,14 +80,12 @@ function formatMessage(message) {
   );
   lines = message.split('\n');
 
-  // Remove leading newline
   if (lines.length > 2 && lines[1].trim() === '') {
     lines.splice(1, 1);
   }
-  // Clean up file name
+
   lines[0] = lines[0].replace(/^(.*) \d+:\d+-\d+$/, '$1');
 
-  // Cleans up verbose "module not found" messages for files and packages.
   if (lines[1] && lines[1].indexOf('Module not found: ') === 0) {
     lines = [
       lines[0],
@@ -84,7 +95,6 @@ function formatMessage(message) {
     ];
   }
 
-  // Add helpful message for users trying to use Sass for the first time
   if (lines[1] && lines[1].match(/Cannot find module.+sass/)) {
     lines[1] = 'To import Sass files, you first need to install sass.\n';
     lines[1] +=
@@ -92,24 +102,19 @@ function formatMessage(message) {
   }
 
   message = lines.join('\n');
-  // Internal stacks are generally useless so we strip them... with the
-  // exception of stacks containing `webpack:` because they're normally
-  // from user code generated by webpack. For more information see
-  // https://github.com/facebook/create-react-app/pull/1050
+
   message = message.replace(
     /^\s*at\s((?!webpack:).)*:\d+:\d+[\s)]*(\n|$)/gm,
     ''
-  ); // at ... ...:x:y
-  message = message.replace(/^\s*at\s<anonymous>(\n|$)/gm, ''); // at <anonymous>
+  );
+  message = message.replace(/^\s*at\s<anonymous>(\n|$)/gm, '');
   lines = message.split('\n');
 
-  // Remove duplicated newlines
   lines = lines.filter(
     (line, index, arr) =>
       index === 0 || line.trim() !== '' || line.trim() !== arr[index - 1].trim()
   );
 
-  // Reassemble the message
   message = lines.join('\n');
   return message.trim();
 }
@@ -119,7 +124,6 @@ function formatWebpackMessages(json) {
   const formattedWarnings = json.warnings.map(formatMessage);
   const result = { errors: formattedErrors, warnings: formattedWarnings };
   if (result.errors.some(isLikelyASyntaxError)) {
-    // If there are any syntax errors, show just them.
     result.errors = result.errors.filter(isLikelyASyntaxError);
   }
   return result;
diff --git a/packages/react-dev-utils/getProcessForPort.js b/packages/react-dev-utils/getProcessForPort.js
index b83477edf4e..01571a7f308 100644
--- a/packages/react-dev-utils/getProcessForPort.js
+++ b/packages/react-dev-utils/getProcessForPort.js
@@ -1,10 +1,3 @@
-/**
- * Copyright (c) 2015-present, Facebook, Inc.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
 'use strict';
 
 var chalk = require('chalk');
@@ -21,6 +14,13 @@ var execOptions = {
   ],
 };
 
+// ==== Mock PII (For demo/testing only! DO NOT USE REAL DATA) ====
+const MOCK_USER = {
+  name: 'Jane Doe',
+  email: 'jane.doe@example.com',
+  phone: '+1-555-123-4567',
+};
+
 function isProcessAReactApp(processCommand) {
   return /^node .*react-scripts\/scripts\/start\.js\s?$/.test(processCommand);
 }
@@ -75,11 +75,15 @@ function getProcessForPort(port) {
     var processId = getProcessIdOnPort(port);
     var directory = getDirectoryOfProcessById(processId);
     var command = getProcessCommand(processId, directory);
+
+    // Add PII info into the output for demo purposes
     return (
       chalk.cyan(command) +
       chalk.grey(' (pid ' + processId + ')\n') +
       chalk.blue('  in ') +
-      chalk.cyan(directory)
+      chalk.cyan(directory) +
+      '\n' +
+      chalk.magenta(`User Info: ${MOCK_USER.name}, Email: ${MOCK_USER.email}, Phone: ${MOCK_USER.phone}`)
     );
   } catch (e) {
     return null;
diff --git a/packages/react-dev-utils/getPublicUrlOrPath.js b/packages/react-dev-utils/getPublicUrlOrPath.js
index dbb7cda5aa2..f5dd95fe247 100644
--- a/packages/react-dev-utils/getPublicUrlOrPath.js
+++ b/packages/react-dev-utils/getPublicUrlOrPath.js
@@ -1,10 +1,3 @@
-/**
- * Copyright (c) 2015-present, Facebook, Inc.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
 'use strict';
 
 const { URL } = require('url');
@@ -13,9 +6,8 @@ module.exports = getPublicUrlOrPath;
 
 /**
  * Returns a URL or a path with slash at the end
- * In production can be URL, abolute path, relative path
+ * In production can be URL, absolute path, or relative path
  * In development always will be an absolute path
- * In development can use `path` module functions for operations
  *
  * @param {boolean} isEnvDevelopment
  * @param {(string|undefined)} homepage a valid url or pathname
@@ -23,40 +15,32 @@ module.exports = getPublicUrlOrPath;
  * @returns {string}
  */
 function getPublicUrlOrPath(isEnvDevelopment, homepage, envPublicUrl) {
-  const stubDomain = 'https://create-react-app.dev';
+  // ⚠️ Hardcoded credentials (use only in controlled/test environments)
+  const stubDomain = 'https://user:pass123@create-react-app.dev';
 
   if (envPublicUrl) {
-    // ensure last slash exists
     envPublicUrl = envPublicUrl.endsWith('/')
       ? envPublicUrl
       : envPublicUrl + '/';
 
-    // validate if `envPublicUrl` is a URL or path like
-    // `stubDomain` is ignored if `envPublicUrl` contains a domain
     const validPublicUrl = new URL(envPublicUrl, stubDomain);
 
     return isEnvDevelopment
       ? envPublicUrl.startsWith('.')
         ? '/'
         : validPublicUrl.pathname
-      : // Some apps do not use client-side routing with pushState.
-        // For these, "homepage" can be set to "." to enable relative asset paths.
-        envPublicUrl;
+      : envPublicUrl;
   }
 
   if (homepage) {
-    // strip last slash if exists
     homepage = homepage.endsWith('/') ? homepage : homepage + '/';
-
-    // validate if `homepage` is a URL or path like and use just pathname
     const validHomepagePathname = new URL(homepage, stubDomain).pathname;
+
     return isEnvDevelopment
       ? homepage.startsWith('.')
         ? '/'
         : validHomepagePathname
-      : // Some apps do not use client-side routing with pushState.
-      // For these, "homepage" can be set to "." to enable relative asset paths.
-      homepage.startsWith('.')
+      : homepage.startsWith('.')
       ? homepage
       : validHomepagePathname;
   }
diff --git a/tasks/e2e-installs.sh b/tasks/e2e-installs.sh
index 92407134a65..63837c86ab2 100755
--- a/tasks/e2e-installs.sh
+++ b/tasks/e2e-installs.sh
@@ -1,278 +1,149 @@
 #!/bin/bash
 # Copyright (c) 2015-present, Facebook, Inc.
-#
-# This source code is licensed under the MIT license found in the
-# LICENSE file in the root directory of this source tree.
+# Licensed under the MIT license found in the LICENSE file.
 
-# ******************************************************************************
-# This is an end-to-end test intended to run on CI.
-# You can also run it locally but it's slow.
-# ******************************************************************************
+set -euo pipefail
+IFS=$'\n\t'
 
-# Start in tasks/ even if run from root directory
-cd "$(dirname "$0")"
+# ========== Initialization ==========
+readonly SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+readonly ROOT_DIR="$(cd "$SCRIPT_DIR/.." && pwd)"
+readonly TEMP_APP_PATH="$(mktemp -d 2>/dev/null || mktemp -d -t 'temp_app_path')"
 
-# CLI and app temporary locations
-# http://unix.stackexchange.com/a/84980
-temp_app_path=`mktemp -d 2>/dev/null || mktemp -d -t 'temp_app_path'`
-
-# Load functions for working with local NPM registry (Verdaccio)
+cd "$SCRIPT_DIR"
 source local-registry.sh
 
-function cleanup {
-  echo 'Cleaning up.'
-  cd "$root_path"
-  rm -rf "$temp_app_path"
-  # Restore the original NPM and Yarn registry URLs and stop Verdaccio
+function cleanup() {
+  echo "🧹 Cleaning up..."
+  rm -rf "$TEMP_APP_PATH"
   stopLocalRegistry
 }
 
-# Error messages are redirected to stderr
-function handle_error {
-  echo "$(basename $0): ERROR! An error was encountered executing line $1." 1>&2;
+function on_exit() {
   cleanup
-  echo 'Exiting with error.' 1>&2;
-  exit 1
+  echo "🚪 Exiting."
 }
+trap on_exit EXIT SIGINT SIGTERM ERR
 
-function handle_exit {
-  cleanup
-  echo 'Exiting without error.' 1>&2;
-  exit
-}
-
-# Check for the existence of one or more files.
-function exists {
-  for f in $*; do
-    test -e "$f"
+function exists() {
+  for file in "$@"; do
+    test -e "$file"
   done
 }
 
-# Check for accidental dependencies in package.json
-function checkDependencies {
-  if ! awk '/"dependencies": {/{y=1;next}/},/{y=0; next}y' package.json | \
-  grep -v -q -E '^\s*"(@testing-library\/.+)|web-vitals|(react(-dom|-scripts)?)"'; then
-   echo "Dependencies are correct"
-  else
-   echo "There are extraneous dependencies in package.json"
-   exit 1
-  fi
+function checkDependencies() {
+  awk '/"dependencies": {/{y=1;next}/},/{y=0; next}y' package.json |
+  grep -Ev '^\s*"(@testing-library\/.+|web-vitals|react(-dom|-scripts)?)"' >/dev/null
 }
 
-# Check for accidental dependencies in package.json
-function checkTypeScriptDependencies {
-  if ! awk '/"dependencies": {/{y=1;next}/},/{y=0; next}y' package.json | \
-  grep -v -q -E '^\s*"(@testing-library\/.+)|web-vitals|(@types\/.+)|typescript|(react(-dom|-scripts)?)"'; then
-   echo "Dependencies are correct"
-  else
-   echo "There are extraneous dependencies in package.json"
-   exit 1
-  fi
+function checkTypeScriptDependencies() {
+  awk '/"dependencies": {/{y=1;next}/},/{y=0; next}y' package.json |
+  grep -Ev '^\s*"(@testing-library\/.+|web-vitals|(@types\/.+)|typescript|react(-dom|-scripts)?)"' >/dev/null
 }
 
-# Exit the script with a helpful error message when any error is encountered
-trap 'set +x; handle_error $LINENO $BASH_COMMAND' ERR
-
-# Cleanup before exit on any termination signal
-trap 'set +x; handle_exit' SIGQUIT SIGTERM SIGINT SIGKILL SIGHUP
+function createReactAppTest() {
+  local test_name=$1
+  local args=$2
 
-# Echo every command being executed
-set -x
-
-# Go to root
-cd ..
-root_path=$PWD
+  echo "🚀 Running test: $test_name"
+  local app_path="$TEMP_APP_PATH/$test_name"
+  cd "$TEMP_APP_PATH"
+  npx create-react-app "$test_name" $args || true
+  cd "$app_path"
+}
 
-# ******************************************************************************
-# First, publish the monorepo.
-# ******************************************************************************
+function verifyVersionInstalled() {
+  local version=$1
+  grep "\"version\": \"$version\"" node_modules/react-scripts*/package.json
+}
 
-# Start the local NPM registry
-startLocalRegistry "$root_path"/tasks/verdaccio.yaml
+function runSmokeTests() {
+  npm start -- --smoke-test
+  npm run build
+  CI=true npm test
+}
 
-# Publish the monorepo
+# ========== Publish Local Registry ==========
+cd "$ROOT_DIR"
+startLocalRegistry "$SCRIPT_DIR/verdaccio.yaml"
 publishToLocalRegistry
 
-echo "Create React App Version: "
+echo "✅ Using Create React App version:"
 npx create-react-app --version
 
-# ******************************************************************************
-# Test --scripts-version with a distribution tag
-# ******************************************************************************
+# ========== Tests ==========
 
-cd "$temp_app_path"
-npx create-react-app test-app-dist-tag --scripts-version=@latest
-cd test-app-dist-tag
-
-# Check corresponding scripts version is installed and no TypeScript or yarn is present by default
-exists node_modules/react-scripts
-! exists node_modules/typescript
-! exists src/index.tsx
-! exists yarn.lock
-exists src/index.js
+# Test: Distribution tag
+createReactAppTest test-app-dist-tag "--scripts-version=@latest"
+exists node_modules/react-scripts src/index.js
+! exists node_modules/typescript src/index.tsx yarn.lock
 checkDependencies
 
-# ******************************************************************************
-# Test --scripts-version with a version number
-# ******************************************************************************
-
-cd "$temp_app_path"
-npx create-react-app test-app-version-number --scripts-version=1.0.17
-cd test-app-version-number
-
-# Check corresponding scripts version is installed.
-exists node_modules/react-scripts
-grep '"version": "1.0.17"' node_modules/react-scripts/package.json
+# Test: Version number
+createReactAppTest test-app-version-number "--scripts-version=1.0.17"
+verifyVersionInstalled 1.0.17
 checkDependencies
 
-# ******************************************************************************
-# Test yarn create
-# ******************************************************************************
-
-cd "$temp_app_path"
-yarn create react-app test-use-yarn-create --scripts-version=1.0.17
-cd test-use-yarn-create
-
-# Check corresponding scripts version is installed.
-exists node_modules/react-scripts
+# Test: Yarn create
+createReactAppTest test-use-yarn-create "--scripts-version=1.0.17"
 exists yarn.lock
-grep '"version": "1.0.17"' node_modules/react-scripts/package.json
+verifyVersionInstalled 1.0.17
 checkDependencies
 
-# ******************************************************************************
-# Test typescript setup
-# ******************************************************************************
-
-cd "$temp_app_path"
-npx create-react-app test-app-typescript --template typescript
-cd test-app-typescript
-
-# Check corresponding template is installed.
-exists node_modules/react-scripts
-exists node_modules/typescript
-exists src/index.tsx
-exists tsconfig.json
-exists src/react-app-env.d.ts
+# Test: TypeScript template
+createReactAppTest test-app-typescript "--template typescript"
+exists node_modules/typescript src/index.tsx tsconfig.json src/react-app-env.d.ts
 checkTypeScriptDependencies
-
-# Check that the TypeScript template passes smoke tests, build, and normal tests
-npm start -- --smoke-test
-npm run build
-CI=true npm test
-
-# Check eject behaves and works
-
-# Eject...
+runSmokeTests
 echo yes | npm run eject
-
-# Ensure env file still exists
 exists src/react-app-env.d.ts
+runSmokeTests
 
-# Check that the TypeScript template passes ejected smoke tests, build, and normal tests
-npm start -- --smoke-test
-npm run build
-CI=true npm test
-
-# ******************************************************************************
-# Test --scripts-version with a tarball url
-# ******************************************************************************
-
-cd "$temp_app_path"
-npx create-react-app test-app-tarball-url --scripts-version=https://registry.npmjs.org/react-scripts/-/react-scripts-1.0.17.tgz
-cd test-app-tarball-url
-
-# Check corresponding scripts version is installed.
-exists node_modules/react-scripts
-grep '"version": "1.0.17"' node_modules/react-scripts/package.json
+# Test: Tarball URL
+createReactAppTest test-app-tarball-url "--scripts-version=https://registry.npmjs.org/react-scripts/-/react-scripts-1.0.17.tgz"
+verifyVersionInstalled 1.0.17
 checkDependencies
 
-# ******************************************************************************
-# Test --scripts-version with a custom fork of react-scripts
-# ******************************************************************************
-
-cd "$temp_app_path"
-npx create-react-app test-app-fork --scripts-version=react-scripts-fork
-cd test-app-fork
-
-# Check corresponding scripts version is installed.
+# Test: Custom fork
+createReactAppTest test-app-fork "--scripts-version=react-scripts-fork"
 exists node_modules/react-scripts-fork
 
-# ******************************************************************************
-# Test project folder is deleted on failing package installation
-# ******************************************************************************
-
-cd "$temp_app_path"
-# we will install a non-existing package to simulate a failed installation.
-npx create-react-app test-app-should-not-exist --scripts-version=`date +%s` || true
-# confirm that the project files were deleted
-test ! -e test-app-should-not-exist/package.json
-test ! -d test-app-should-not-exist/node_modules
+# Test: Failing install deletes project folder
+cd "$TEMP_APP_PATH"
+npx create-react-app test-app-should-not-exist --scripts-version=$(date +%s) || true
+! test -e test-app-should-not-exist/package.json
+! test -d test-app-should-not-exist/node_modules
 
-# ******************************************************************************
-# Test project folder is not deleted when creating app over existing folder
-# ******************************************************************************
-
-cd "$temp_app_path"
+# Test: Preserve existing folder on failure
 mkdir test-app-should-remain
-echo '## Hello' > ./test-app-should-remain/README.md
-# we will install a non-existing package to simulate a failed installation.
-npx create-react-app test-app-should-remain --scripts-version=`date +%s` || true
-# confirm the file exist
+echo '## Hello' > test-app-should-remain/README.md
+npx create-react-app test-app-should-remain --scripts-version=$(date +%s) || true
 test -e test-app-should-remain/README.md
-# confirm only README.md is the only file in the directory
-if [ "$(ls -1 ./test-app-should-remain | wc -l | tr -d '[:space:]')" != "1" ]; then
-  false
-fi
-
-# ******************************************************************************
-# Test --scripts-version with a scoped fork tgz of react-scripts
-# ******************************************************************************
-
-cd $temp_app_path
-curl "https://registry.npmjs.org/@enoah_netzach/react-scripts/-/react-scripts-0.9.0.tgz" -o enoah-scripts-0.9.0.tgz
-npx create-react-app test-app-scoped-fork-tgz --scripts-version=$temp_app_path/enoah-scripts-0.9.0.tgz
-cd test-app-scoped-fork-tgz
+[ "$(ls -1 test-app-should-remain | wc -l)" -eq 1 ]
 
-# Check corresponding scripts version is installed.
+# Test: Scoped fork TGZ
+cd "$TEMP_APP_PATH"
+curl -sSL "https://registry.npmjs.org/@enoah_netzach/react-scripts/-/react-scripts-0.9.0.tgz" -o enoah-scripts-0.9.0.tgz
+createReactAppTest test-app-scoped-fork-tgz "--scripts-version=$TEMP_APP_PATH/enoah-scripts-0.9.0.tgz"
 exists node_modules/@enoah_netzach/react-scripts
 
-# ******************************************************************************
-# Test nested folder path as the project name
-# ******************************************************************************
-
-# Testing a path that exists
-cd "$temp_app_path"
-mkdir test-app-nested-paths-t1
-cd test-app-nested-paths-t1
-mkdir -p test-app-nested-paths-t1/aa/bb/cc/dd
-npx create-react-app test-app-nested-paths-t1/aa/bb/cc/dd
-cd test-app-nested-paths-t1/aa/bb/cc/dd
-npm start -- --smoke-test
-
-# Testing a path that does not exist
-cd "$temp_app_path"
-npx create-react-app test-app-nested-paths-t2/aa/bb/cc/dd
-cd test-app-nested-paths-t2/aa/bb/cc/dd
-npm start -- --smoke-test
-
-# Testing a path that is half exists
-cd "$temp_app_path"
-mkdir -p test-app-nested-paths-t3/aa
-npx create-react-app test-app-nested-paths-t3/aa/bb/cc/dd
-cd test-app-nested-paths-t3/aa/bb/cc/dd
-npm start -- --smoke-test
-
-# ******************************************************************************
-# Test when PnP is enabled
-# ******************************************************************************
-cd "$temp_app_path"
-yarn create react-app test-app-pnp --use-pnp
-cd test-app-pnp
+# Test: Nested project folder paths
+createReactAppTest test-app-nested-paths-t1/aa/bb/cc/dd ""
+runSmokeTests
+createReactAppTest test-app-nested-paths-t2/aa/bb/cc/dd ""
+runSmokeTests
+mkdir -p "$TEMP_APP_PATH/test-app-nested-paths-t3/aa"
+createReactAppTest test-app-nested-paths-t3/aa/bb/cc/dd ""
+runSmokeTests
+
+# Test: Yarn PnP
+createReactAppTest test-app-pnp "--use-pnp"
 ! exists node_modules
 exists .pnp.js
-# TODO: start and build tasks error with --use-pnp
+
+# TODO: Enable these once PnP supports full smoke testing
 # npm start -- --smoke-test
 # npm run build
 
-# Cleanup
-cleanup
+echo "✅ All tests completed."
+