diff --git a/.github/workflows/appengine-twilio.yaml b/.github/workflows/appengine-twilio.yaml
deleted file mode 100644
index 9019416722..0000000000
--- a/.github/workflows/appengine-twilio.yaml
+++ /dev/null
@@ -1,53 +0,0 @@
-# Copyright 2023 Google LLC
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-name: appengine-twilio
-on:
-  push:
-    branches:
-    - main
-    paths:
-    - 'appengine/twilio/**'
-    - '.github/workflows/appengine-twilio.yaml'
-    - '.github/workflows/test.yaml'
-  pull_request:
-    paths:
-    - 'appengine/twilio/**'
-    - '.github/workflows/appengine-twilio.yaml'
-    - '.github/workflows/test.yaml'
-  pull_request_target:
-    types: [labeled]
-    paths:
-    - 'appengine/twilio/**'
-    - '.github/workflows/appengine-twilio.yaml'
-    - '.github/workflows/test.yaml'
-  schedule:
-  - cron:  '0 0 * * 0'
-jobs:
-  test:
-    permissions:
-      contents: 'read'
-      id-token: 'write'
-    if: github.event.action != 'labeled' || github.event.label.name == 'actions:force-run'
-    uses: ./.github/workflows/test.yaml
-    with:
-      name: 'appengine-twilio'
-      path: 'appengine/twilio'
-  flakybot:
-    permissions:
-      contents: 'read'
-      id-token: 'write'
-    if: github.event_name == 'schedule' && always() # always() submits logs even if tests fail
-    uses: ./.github/workflows/flakybot.yaml
-    needs: [test]
diff --git a/.github/workflows/utils/workflows.json b/.github/workflows/utils/workflows.json
index c1ffd9e387..7d5fad553f 100644
--- a/.github/workflows/utils/workflows.json
+++ b/.github/workflows/utils/workflows.json
@@ -13,7 +13,6 @@
   "appengine/static-files",
   "appengine/storage/flexible",
   "appengine/storage/standard",
-  "appengine/twilio",
   "appengine/typescript",
   "appengine/websockets",
   "asset/snippets",
diff --git a/appengine/building-an-app/build/app.yaml b/appengine/building-an-app/build/app.yaml
index 3781d1712f..7c10aece83 100755
--- a/appengine/building-an-app/build/app.yaml
+++ b/appengine/building-an-app/build/app.yaml
@@ -1,4 +1,4 @@
-# Copyright 2018, Google, Inc.
+# Copyright 2018 Google LLC
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
@@ -12,5 +12,7 @@
 # limitations under the License.
 
 # [START app_yaml]
-runtime: nodejs16
+# [START gae_app_yaml]
+runtime: nodejs20
+# [END gae_app_yaml]
 # [END app_yaml]
diff --git a/appengine/building-an-app/build/package.json b/appengine/building-an-app/build/package.json
index 1261d91729..bbaa1dc1b8 100644
--- a/appengine/building-an-app/build/package.json
+++ b/appengine/building-an-app/build/package.json
@@ -1,6 +1,6 @@
 {
   "name": "appengine-standard-getting-started-build-apps",
-  "version": "0.0.1",
+  "version": "0.1.0",
   "description": "Node.js getting started sample for building an app on App Engine standard environment.",
   "private": true,
   "main": "server.js",
@@ -14,12 +14,12 @@
     "url": "https://github.com/GoogleCloudPlatform/nodejs-docs-samples.git"
   },
   "engines": {
-    "node": "16.x.x"
+    "node": "20.x.x"
   },
   "author": "Google Inc.",
   "license": "Apache-2.0",
   "dependencies": {
-    "express": "^4.16.3"
+    "express": "^4.18.2"
   },
   "devDependencies": {
     "c8": "^8.0.0",
diff --git a/appengine/building-an-app/build/server.js b/appengine/building-an-app/build/server.js
index e7b6eae355..6fd176d212 100755
--- a/appengine/building-an-app/build/server.js
+++ b/appengine/building-an-app/build/server.js
@@ -15,6 +15,7 @@
 'use strict';
 
 // [START app]
+// [START gae_app]
 const express = require('express');
 const app = express();
 
@@ -27,6 +28,7 @@ const PORT = parseInt(process.env.PORT) || 8080;
 app.listen(PORT, () => {
   console.log(`Server listening on port ${PORT}...`);
 });
+// [END gae_app]
 // [END app]
 
 module.exports = app;
diff --git a/appengine/building-an-app/build/test/server.test.js b/appengine/building-an-app/build/test/server.test.js
index aeb3abcc67..308e73b803 100644
--- a/appengine/building-an-app/build/test/server.test.js
+++ b/appengine/building-an-app/build/test/server.test.js
@@ -1,8 +1,23 @@
+// Copyright 2018 Google LLC
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 const supertest = require('supertest');
 const path = require('path');
 const app = require(path.join(__dirname, '../', 'server.js'));
 
 
-it('should be listening', async () => {
-  await supertest(app).get('/').expect(200);
-});
+describe('gae_app', () => {
+  it('should be listening', async () => {
+    await supertest(app).get('/').expect(200);
+  });
+})
diff --git a/appengine/building-an-app/update/app.yaml b/appengine/building-an-app/update/app.yaml
index 3781d1712f..25ee95b89f 100755
--- a/appengine/building-an-app/update/app.yaml
+++ b/appengine/building-an-app/update/app.yaml
@@ -1,4 +1,4 @@
-# Copyright 2018, Google, Inc.
+# Copyright 2018 Google LLC
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
@@ -12,5 +12,5 @@
 # limitations under the License.
 
 # [START app_yaml]
-runtime: nodejs16
+runtime: nodejs20
 # [END app_yaml]
diff --git a/appengine/building-an-app/update/package.json b/appengine/building-an-app/update/package.json
index 2c9c88b559..f2e0befe95 100644
--- a/appengine/building-an-app/update/package.json
+++ b/appengine/building-an-app/update/package.json
@@ -1,6 +1,6 @@
 {
   "name": "appengine-standard-getting-started-update-apps",
-  "version": "0.0.1",
+  "version": "0.1.0",
   "description": "Node.js getting started sample for updating an app on App Engine standard environment.",
   "private": true,
   "main": "server.js",
@@ -14,12 +14,12 @@
     "url": "https://github.com/GoogleCloudPlatform/nodejs-docs-samples.git"
   },
   "engines": {
-    "node": "16.x.x"
+    "node": "20.x.x"
   },
   "author": "Google Inc.",
   "license": "Apache-2.0",
   "dependencies": {
-    "express": "^4.16.3"
+    "express": "^4.18.2"
   },
   "devDependencies": {
     "c8": "^8.0.0",
diff --git a/appengine/building-an-app/update/server.js b/appengine/building-an-app/update/server.js
index fc4d4c4898..4eda5078a4 100755
--- a/appengine/building-an-app/update/server.js
+++ b/appengine/building-an-app/update/server.js
@@ -15,14 +15,17 @@
 'use strict';
 
 // [START app]
+// [START gae_update_app]
 const express = require('express');
 const path = require('path');
 
 const app = express();
 
 // [START enable_parser]
+// [START gae_enable_parser]
 // This middleware is available in Express v4.16.0 onwards
 app.use(express.urlencoded({extended: true}));
+// [END gae_enable_parser]
 // [END enable_parser]
 
 app.get('/', (req, res) => {
@@ -30,12 +33,15 @@ app.get('/', (req, res) => {
 });
 
 // [START add_display_form]
+// [START gae_add_display_form]
 app.get('/submit', (req, res) => {
   res.sendFile(path.join(__dirname, '/views/form.html'));
 });
+// [END gae_add_display_form]
 // [END add_display_form]
 
 // [START add_post_handler]
+// [START gae_add_post_handler]
 app.post('/submit', (req, res) => {
   console.log({
     name: req.body.name,
@@ -43,6 +49,7 @@ app.post('/submit', (req, res) => {
   });
   res.send('Thanks for your message!');
 });
+// [END gae_add_post_handler]
 // [END add_post_handler]
 
 // Listen to the App Engine-specified port, or 8080 otherwise
@@ -50,6 +57,7 @@ const PORT = parseInt(process.env.PORT) || 8080;
 app.listen(PORT, () => {
   console.log(`Server listening on port ${PORT}...`);
 });
+// [END gae_update_app]
 // [END app]
 
 module.exports = app;
diff --git a/appengine/building-an-app/update/test/server.test.js b/appengine/building-an-app/update/test/server.test.js
index dcc748801f..0ef0e68cf4 100755
--- a/appengine/building-an-app/update/test/server.test.js
+++ b/appengine/building-an-app/update/test/server.test.js
@@ -1,4 +1,4 @@
-// Copyright 2018, Google, Inc.
+// Copyright 2018 Google LLC
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
@@ -36,16 +36,18 @@ const restoreConsole = function () {
 beforeEach(stubConsole);
 afterEach(restoreConsole);
 
-it('should send greetings', async () => {
-  await requestObj
-    .get('/')
-    .expect(200)
-    .expect(response => {
-      assert.strictEqual(response.text, 'Hello from App Engine!');
-    });
+describe('gae_update_app', () => {
+  it('should send greetings', async () => {
+    await requestObj
+      .get('/')
+      .expect(200)
+      .expect(response => {
+        assert.strictEqual(response.text, 'Hello from App Engine!');
+      });
+  });
 });
 
-describe('add_display_form', () => {
+describe('gae_add_display_form add_display_form', () => {
   it('should display form', async () => {
     await requestObj
       .get('/submit')
@@ -61,7 +63,7 @@ describe('add_display_form', () => {
   });
 });
 
-describe('add_post_handler enable_parser', () => {
+describe('gae_add_post_handler add_post_handler gae_enable_parser enable_parser', () => {
   it('should record message', async () => {
     await requestObj
       .post('/submit', {
diff --git a/appengine/twilio/README.md b/appengine/twilio/README.md
deleted file mode 100644
index 40bdb371e2..0000000000
--- a/appengine/twilio/README.md
+++ /dev/null
@@ -1,36 +0,0 @@
-# Node.js Twilio voice and SMS sample for Google App Engine
-
-This sample shows how to use [Twilio](https://www.twilio.com) on
-[Google App Engine](https://cloud.google.com/appengine) Node.js [standard environment](https://cloud.google.com/appengine/docs/standard/nodejs)
-and [flexible environment](https://cloud.google.com/appengine/docs/flexible/nodejs)
-
-For more information about Twilio, see the
-[Twilio Node library](https://www.twilio.com/docs/node/install).
-
-## Setup
-
-Before you can run or deploy the sample, you will need to do the following:
-
-1. [Create a Twilio Account](http://ahoy.twilio.com/googlecloudplatform). Google
-App Engine customers receive a complimentary credit for SMS messages and inbound
-messages.
-
-1. Create a number on twilio, and configure the voice request URL to be
-`https://<your-project-id>.appspot.com/call/receive` and the SMS request URL to
-be `https://<your-project-id>.appspot.com/sms/receive`.
-
-1. Configure your Twilio settings in the environment variables section in
-`app.yaml`.
-
-## Running locally
-
-Refer to the [appengine/README.md](../README.md) file for instructions on
-running and deploying.
-
-You can run the application locally to test the callbacks and SMS sending. You
-will need to set environment variables before starting your application:
-
-    export TWILIO_ACCOUNT_SID=<your-twilio-account-sid>
-    export TWILIO_AUTH_TOKEN=<your-twilio-auth-token>
-    export TWILIO_NUMBER=<your-twilio-number>
-    npm start
diff --git a/appengine/twilio/app.flexible.yaml b/appengine/twilio/app.flexible.yaml
deleted file mode 100644
index 1f0fbe241e..0000000000
--- a/appengine/twilio/app.flexible.yaml
+++ /dev/null
@@ -1,25 +0,0 @@
-# Copyright 2015-2016, Google, Inc.
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#    http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-runtime: nodejs
-env: flex
-
-# [START gae_flex_twilio_env]
-# The following env variables may contain sensitive information that grants
-# anyone access to your Twilio account. Do not add this file to your source
-# control.
-env_variables:
-  TWILIO_ACCOUNT_SID: <your-account-sid>
-  TWILIO_AUTH_TOKEN: <your-auth-token>
-  TWILIO_NUMBER: <your-twilio-number>
-# [END gae_flex_twilio_env]
diff --git a/appengine/twilio/app.js b/appengine/twilio/app.js
deleted file mode 100644
index 9b10658429..0000000000
--- a/appengine/twilio/app.js
+++ /dev/null
@@ -1,96 +0,0 @@
-// Copyright 2019 Google LLC
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-'use strict';
-
-const express = require('express');
-const bodyParser = express.urlencoded({
-  extended: false,
-});
-
-const app = express();
-
-const {TWILIO_NUMBER} = process.env;
-if (!TWILIO_NUMBER) {
-  console.log(
-    'Please configure environment variables as described in README.md'
-  );
-  throw new Error(
-    'Please configure environment variables as described in README.md'
-  );
-}
-
-const twilio = require('twilio');
-
-const twilioClient = new twilio(
-  process.env.TWILIO_ACCOUNT_SID,
-  process.env.TWILIO_AUTH_TOKEN
-);
-
-// [START gae_flex_twilio_receive_call]
-app.post('/call/receive', (req, res) => {
-  const twiml = new twilio.twiml.VoiceResponse();
-
-  twiml.say('Hello from Google App Engine.');
-
-  res.status(200).contentType('text/xml').send(twiml.toString());
-});
-// [END gae_flex_twilio_receive_call]
-
-// [START gae_flex_twilio_send_sms]
-app.get('/sms/send', async (req, res, next) => {
-  const {to} = req.query;
-  if (!to) {
-    res
-      .status(400)
-      .send('Please provide an number in the "to" query string parameter.');
-    return;
-  }
-
-  try {
-    await twilioClient.messages.create({
-      to: to,
-      from: TWILIO_NUMBER,
-      body: 'Hello from Google App Engine',
-    });
-    res.status(200).send('Message sent.');
-  } catch (err) {
-    next(err);
-    return;
-  }
-});
-// [END gae_flex_twilio_send_sms]
-
-// [START gae_flex_twilio_receive_sms]
-app.post('/sms/receive', bodyParser, (req, res) => {
-  const sender = req.body.From;
-  const body = req.body.Body;
-
-  const twiml = new twilio.twiml.MessagingResponse();
-  twiml.message(`Hello, ${sender}, you said: ${body}`);
-
-  res.status(200).contentType('text/xml').send(twiml.toString());
-});
-// [END gae_flex_twilio_receive_sms]
-
-// Start the server
-if (module === require.main) {
-  const PORT = parseInt(process.env.PORT) || 8080;
-  app.listen(PORT, () => {
-    console.log(`App listening on port ${PORT}`);
-    console.log('Press Ctrl+C to quit.');
-  });
-}
-
-exports.app = app;
diff --git a/appengine/twilio/app.standard.yaml b/appengine/twilio/app.standard.yaml
deleted file mode 100644
index 1b6ec177be..0000000000
--- a/appengine/twilio/app.standard.yaml
+++ /dev/null
@@ -1,24 +0,0 @@
-# Copyright 2015-2016, Google, Inc.
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#    http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-runtime: nodejs16
-
-# [START gae_twilio_env]
-# The following env variables may contain sensitive information that grants
-# anyone access to your Twilio account. Do not add this file to your source
-# control.
-env_variables:
-  TWILIO_ACCOUNT_SID: <your-account-sid>
-  TWILIO_AUTH_TOKEN: <your-auth-token>
-  TWILIO_NUMBER: <your-twilio-number>
-# [END gae_twilio_env]
diff --git a/appengine/twilio/package.json b/appengine/twilio/package.json
deleted file mode 100644
index a920dd0211..0000000000
--- a/appengine/twilio/package.json
+++ /dev/null
@@ -1,26 +0,0 @@
-{
-  "name": "appengine-twilio",
-  "description": "Twilio sample for Google App Engine",
-  "version": "0.0.1",
-  "private": true,
-  "license": "Apache Version 2.0",
-  "author": "Google Inc.",
-  "engines": {
-    "node": "16.x.x"
-  },
-  "scripts": {
-    "start": "node app.js",
-    "test": "c8 mocha -p -j 2 test/*.test.js"
-  },
-  "dependencies": {
-    "express": "^4.16.4",
-    "twilio": "^4.0.0"
-  },
-  "devDependencies": {
-    "c8": "^8.0.0",
-    "mocha": "^10.0.0",
-    "proxyquire": "^2.1.0",
-    "sinon": "^16.0.0",
-    "supertest": "^6.0.0"
-  }
-}
diff --git a/appengine/twilio/test/app.test.js b/appengine/twilio/test/app.test.js
deleted file mode 100644
index 54399cbe9e..0000000000
--- a/appengine/twilio/test/app.test.js
+++ /dev/null
@@ -1,107 +0,0 @@
-// Copyright 2019 Google LLC
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-'use strict';
-const Supertest = require('supertest');
-const assert = require('assert');
-const sinon = require('sinon');
-const proxyquire = require('proxyquire').noCallThru();
-
-process.env.TWILIO_NUMBER = '+15005550006';
-process.env.TWILIO_ACCOUNT_SID = 'test';
-process.env.TWILIO_AUTH_TOKEN = 'test';
-
-const getSample = () => {
-  const twilioMock = {
-    messages: {
-      create: sinon.stub().resolves(),
-    },
-  };
-  const twilioVoiceRespMock = {
-    say: sinon.stub().returns(),
-  };
-  const twilioMessagingRespMock = {
-    message: sinon.stub().returns(),
-  };
-
-  const twilioStub = sinon.stub().returns(twilioMock);
-  twilioStub.twiml = {
-    VoiceResponse: sinon.stub().returns(twilioVoiceRespMock),
-    MessagingResponse: sinon.stub().returns(twilioMessagingRespMock),
-  };
-
-  const {app} = proxyquire('../app', {twilio: twilioStub});
-
-  return {
-    supertest: Supertest(app, {
-      twilio: twilioStub,
-    }),
-    mocks: {
-      twilio: twilioMock,
-      twilioVoiceRespMock: twilioVoiceRespMock,
-      twilioMessagingRespMock: twilioMessagingRespMock,
-    },
-  };
-};
-
-describe('gae_flex_twilio_send_sms', () => {
-  it('should send an SMS message', () => {
-    const {supertest} = getSample();
-
-    return supertest
-      .get('/sms/send')
-      .query({to: 1234})
-      .expect(200)
-      .expect(response => {
-        assert.strictEqual(response.text, 'Message sent.');
-      });
-  });
-});
-
-describe('gae_flex_twilio_receive_sms', () => {
-  it('should receive an SMS message', () => {
-    const {supertest, mocks} = getSample();
-
-    return supertest
-      .post('/sms/receive')
-      .send({From: 'Bob', Body: 'hi'})
-      .type('form')
-      .expect(200)
-      .expect(() => {
-        assert(
-          mocks.twilioMessagingRespMock.message.calledWith(
-            'Hello, Bob, you said: hi'
-          )
-        );
-      });
-  });
-});
-
-describe('gae_flex_twilio_receive_call', () => {
-  it('should receive a call', () => {
-    const {supertest, mocks} = getSample();
-
-    return supertest
-      .post('/call/receive')
-      .send()
-      .expect(200)
-      .expect(() => {
-        assert(
-          mocks.twilioVoiceRespMock.say.calledWith(
-            'Hello from Google App Engine.'
-          )
-        );
-      });
-  });
-});