diff --git a/CODEOWNERS b/CODEOWNERS
index fd5d65262d3c..023236e41a30 100644
--- a/CODEOWNERS
+++ b/CODEOWNERS
@@ -25,6 +25,7 @@ packages/service-proxy/* @raymondfeng
 packages/testlab/* @bajtos
 examples/todo/* @bajtos @hacksparrow
 examples/express-composition/* @nabdelgadir
+examples/greeter-extension/* @raymondfeng
 examples/hello-world/* @b-admike
 examples/log-extension/* @hacksparrow
 examples/rpc-server/* @hacksparrow
diff --git a/docs/site/MONOREPO.md b/docs/site/MONOREPO.md
index a83ce425da63..725788c84499 100644
--- a/docs/site/MONOREPO.md
+++ b/docs/site/MONOREPO.md
@@ -15,6 +15,7 @@ The [loopback-next](https://github.com/strongloop/loopback-next) repository uses
 | [core](https://github.com/strongloop/loopback-next/tree/master/packages/core)                                       | @loopback/core                        | Define and implement core constructs such as Application and Component                                                                                                                                                                                                                           |
 | [docs](https://github.com/strongloop/loopback-next/tree/master/docs)                                                | @loopback/docs                        | Documentation files rendered at [https://loopback.io](https://loopback.io)                                                                                                                                                                                                                       |
 | [example-express-composition](https://github.com/strongloop/loopback-next/tree/master/examples/express-composition) | @loopback/example-express-composition | A simple Express application that uses LoopBack 4 REST API                                                                                                                                                                                                                                       |
+| [example-greeter-extension](https://github.com/strongloop/loopback-next/tree/master/examples/greeter-extension)     | @loopback/example-greeter-extension   | An example showing how to implement extension point/extension pattern using LoopBack 4                                                                                                                                                                                                           |
 | [example-hello-world](https://github.com/strongloop/loopback-next/tree/master/examples/hello-world)                 | @loopback/example-hello-world         | A simple hello-world application using LoopBack 4                                                                                                                                                                                                                                                |
 | [example-log-extension](https://github.com/strongloop/loopback-next/tree/master/examples/log-extension)             | @loopback/example-log-extension       | An example showing how to write a complex log extension for LoopBack 4                                                                                                                                                                                                                           |
 | [example-rpc-server](https://github.com/strongloop/loopback-next/tree/master/examples/rpc-server)                   | @loopback/example-rpc-server          | An example RPC server and application to demonstrate the creation of your own custom server                                                                                                                                                                                                      |
diff --git a/examples/greeter-extension/.npmrc b/examples/greeter-extension/.npmrc
new file mode 100644
index 000000000000..cafe685a112d
--- /dev/null
+++ b/examples/greeter-extension/.npmrc
@@ -0,0 +1 @@
+package-lock=true
diff --git a/examples/greeter-extension/.prettierignore b/examples/greeter-extension/.prettierignore
new file mode 100644
index 000000000000..c6911da9e1e8
--- /dev/null
+++ b/examples/greeter-extension/.prettierignore
@@ -0,0 +1,2 @@
+dist
+*.json
diff --git a/examples/greeter-extension/.prettierrc b/examples/greeter-extension/.prettierrc
new file mode 100644
index 000000000000..f58b81dd7be2
--- /dev/null
+++ b/examples/greeter-extension/.prettierrc
@@ -0,0 +1,6 @@
+{
+  "bracketSpacing": false,
+  "singleQuote": true,
+  "printWidth": 80,
+  "trailingComma": "all"
+}
diff --git a/examples/greeter-extension/.vscode/settings.json b/examples/greeter-extension/.vscode/settings.json
new file mode 100644
index 000000000000..4a90df17452c
--- /dev/null
+++ b/examples/greeter-extension/.vscode/settings.json
@@ -0,0 +1,21 @@
+{
+  "editor.rulers": [80],
+  "editor.tabCompletion": "on",
+  "editor.tabSize": 2,
+  "editor.trimAutoWhitespace": true,
+  "editor.formatOnSave": true,
+
+  "files.exclude": {
+    "**/.DS_Store": true,
+    "**/.git": true,
+    "**/.hg": true,
+    "**/.svn": true,
+    "**/CVS": true,
+    "dist": true,
+  },
+  "files.insertFinalNewline": true,
+  "files.trimTrailingWhitespace": true,
+
+  "tslint.ignoreDefinitionFiles": true,
+  "typescript.tsdk": "./node_modules/typescript/lib"
+}
diff --git a/examples/greeter-extension/.vscode/tasks.json b/examples/greeter-extension/.vscode/tasks.json
new file mode 100644
index 000000000000..c3003aa764e3
--- /dev/null
+++ b/examples/greeter-extension/.vscode/tasks.json
@@ -0,0 +1,29 @@
+{
+  // See https://go.microsoft.com/fwlink/?LinkId=733558
+  // for the documentation about the tasks.json format
+  "version": "2.0.0",
+  "tasks": [
+    {
+      "label": "Watch and Compile Project",
+      "type": "shell",
+      "command": "npm",
+      "args": ["--silent", "run", "build:watch"],
+      "group": {
+        "kind": "build",
+        "isDefault": true
+      },
+      "problemMatcher": "$tsc-watch"
+    },
+    {
+      "label": "Build, Test and Lint",
+      "type": "shell",
+      "command": "npm",
+      "args": ["--silent", "run", "test:dev"],
+      "group": {
+        "kind": "test",
+        "isDefault": true
+      },
+      "problemMatcher": ["$tsc", "$tslint5"]
+    }
+  ]
+}
diff --git a/examples/greeter-extension/LICENSE b/examples/greeter-extension/LICENSE
new file mode 100644
index 000000000000..6c4a691c6bb6
--- /dev/null
+++ b/examples/greeter-extension/LICENSE
@@ -0,0 +1,25 @@
+Copyright (c) Author 2018. All Rights Reserved.
+Node module: @loopback/example-greeter-extension
+This project is licensed under the MIT License, full text below.
+
+--------
+
+MIT license
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
diff --git a/examples/greeter-extension/README.md b/examples/greeter-extension/README.md
new file mode 100644
index 000000000000..d8f65df2fc87
--- /dev/null
+++ b/examples/greeter-extension/README.md
@@ -0,0 +1,352 @@
+# @loopback/example-greeter-extension
+
+This example project illustrates how to implement the
+[Extension Point/extension pattern](https://wiki.eclipse.org/FAQ_What_are_extensions_and_extension_points%3F),
+which promotes loose coupling and offers great extensibility. There are many use
+cases in LoopBack 4 that fit into design pattern. For example:
+
+- `@loopback/boot` uses `BootStrapper` that delegates to `Booters` to handle
+  different types of artifacts
+- `@loopback/rest` uses `RequestBodyParser` that finds the corresponding
+  `BodyParsers` to parse request body encoded in different media types
+
+## Overview
+
+We'll use the following scenario to walk through important steps to organize the
+`greet` service that allows extensible languages - each of them being supported
+by a `Greeter` extension.
+
+![greeters](greeters.png)
+
+Various constructs from LoopBack 4, such as `Context`, `@inject.*`, and
+`Component` are used to build the service in an extensible fashion.
+
+## Define an extension point
+
+In our scenario, we want to allow other modules to extend or customize how
+people are greeted in different languages. To achieve that, we declare the
+`greeter` extension point, which declares a contract as TypeScript interfaces
+that extensions must conform to.
+
+### Define interface for extensions
+
+An extension point interacts with unknown number of extensions. It needs to
+define one or more interfaces as contracts that each extension must implement.
+
+```ts
+/**
+ * Typically an extension point defines an interface as the contract for
+ * extensions to implement
+ */
+export interface Greeter {
+  language: string;
+  greet(name: string): string;
+}
+```
+
+### Define class for the extension point
+
+Typically an extension point is defined as a TypeScript class and bound to a
+context. In our case, we mark `GreetingService` as the extension point that
+needs to access a list of greeters.
+
+```ts
+/**
+ * An extension point for greeters that can greet in different languages
+ */
+export class GreetingService {
+  constructor(
+    /**
+     * Inject a getter function to fetch greeters (bindings tagged with
+     * 'greeter')
+     */
+    @inject.getter(bindingTagFilter({extensionPoint: 'greeter'}))
+    private greeters: Getter<Greeter[]>,
+  ) {}
+  // ...
+}
+```
+
+To customize metadata such as `id` for the extension point, we can use
+`@extensionPoint` to decorate the class, such as:
+
+```ts
+@extensionPoint('greeter')
+export class GreetingService {}
+```
+
+#### Access extensions for a given extension point
+
+To simplify access to extensions for a given extension point, we use dependency
+injection to receive a `getter` function that gives us a list of greeters.
+
+```ts
+@extensionPoint('greeter')
+export class GreetingService {
+  constructor(
+    /**
+     * Inject a getter function to fetch greeters (bindings tagged with
+     * 'greeter')
+     */
+    @extensions() // Sugar for @inject.getter(filterByTag({extensionPoint: 'greeter'}))
+    private greeters: Getter<Greeter[]>, // ...
+  ) {}
+}
+```
+
+Please note that it's possible to add/remove greeters after the extension point
+is instantiated. The injected getter function always pick up the latest list of
+greeters. For example:
+
+```ts
+// Get the latest list of greeters
+const greeters = await this.greeters();
+```
+
+#### Implement the delegation logic
+
+Typically, the extension point implementation will get a list of registered
+extensions. For example, when a person needs to be greeted in a specific
+language, the code iterates through all greeters to find an instance that
+matches the language. In this module, `GreetingService` implements the `greet`
+operation which uses `findGreeter` to find a greeter and produces a greeting for
+the given language.
+
+```ts
+export class GreetingService {
+  // ...
+  /**
+   * Find a greeter that can speak the given language
+   * @param language Language code for the greeting
+   */
+  async findGreeter(language: string) {
+    // Get the latest list of greeters
+    const greeters = await this.greeters();
+    // Find a greeter that can speak the given language
+    return greeters.find(g => g.language === language);
+  }
+
+  /**
+   * Greet in the given language
+   * @param language Language code
+   * @param name Name
+   */
+  async greet(language: string, name: string): Promise<string> {
+    let greeting: string = '';
+
+    const greeter = await this.findGreeter(language);
+    if (greeter) {
+      greeting = greeter.greet(name);
+    } else {
+      // Fall back to English
+      greeting = `Hello, ${name}`;
+    }
+    if (this.options && this.options.color) {
+      greeting = chalk.keyword(this.options.color)(greeting);
+    }
+    return greeting;
+  }
+}
+```
+
+## Implement an extension
+
+Modules that want to connect to `greeter` extension point must implement
+`Greeter` interface in their extension. The key attribute is that the
+`GreetingService` being extended knows nothing about the module that is
+connecting to it beyond the scope of that contract. This allows `greeters` built
+by different individuals or companies to interact seamlessly, even without their
+knowing much about one another.
+
+```ts
+import {Greeter, asGreeter} from '../types';
+import {bind, inject} from '@loopback/context';
+
+/**
+ * Options for the Chinese greeter
+ */
+export interface ChineseGreeterOptions {
+  // Name first, default to `true`
+  nameFirst: boolean;
+}
+
+/**
+ * A greeter implementation for Chinese
+ */
+@bind(asGreeter)
+export class ChineseGreeter implements Greeter {
+  language = 'zh';
+
+  constructor(
+    /**
+     * Inject the configuration for ChineseGreeter
+     */
+    @inject('greeters.ChineseGreeter.options', {optional: true})
+    private options: ChineseGreeterOptions = {nameFirst: true},
+  ) {}
+
+  greet(name: string) {
+    if (this.options && this.options.nameFirst === false) {
+      return `你好，${name}！`;
+    }
+    return `${name}，你好！`;
+  }
+}
+```
+
+Please note we use
+[`@bind`](https://loopback.io/doc/en/lb4/Binding.html#configure-binding-attributes-for-a-class)
+to customize how the class can be bound. In this case, `asGreeter` is a binding
+template function, which is equivalent as configuring a binding with
+`{extensionPoint: 'greeter'}` tag and in the `SINGLETON` scope.
+
+```ts
+/**
+ * A binding template for greeter extensions
+ * @param binding
+ */
+export const asGreeter: BindingTemplate = binding =>
+  binding.inScope(BindingScope.SINGLETON).tag({extensionPoint: 'greeter'});
+```
+
+## Register an extension point
+
+To register an extension point, we simply bind the implementation class to a
+`Context`. For example:
+
+```ts
+app
+  .bind('services.GreetingService')
+  .toClass(GreetingService)
+  .inScope(BindingScope.SINGLETON);
+```
+
+**NOTE**: Your extension point may choose to use a different binding scope.
+
+The process can be automated with a component:
+
+```ts
+import {createBindingFromClass} from '@loopback/context';
+import {Component} from '@loopback/core';
+import {GreetingService} from './greeting-service';
+import {GREETING_SERVICE} from './keys';
+
+/**
+ * Define a component to register the greeter extension point and built-in
+ * extensions
+ */
+export class GreeterComponent implements Component {
+  bindings = [
+    createBindingFromClass(GreetingService, {
+      key: GREETING_SERVICE,
+    }),
+    // ...
+  ];
+}
+```
+
+## Register extensions
+
+To connect an extension to an extension point, we just have to bind the
+extension to the `Context` and tag the binding with
+`{extensionPoint: 'greeter'}`.
+
+```ts
+app
+  .bind('greeters.FrenchGreeter')
+  .toClass(FrenchGreeter)
+  .apply(asGreeter);
+```
+
+Or
+
+```ts
+app.add(createBindingFromClass(FrenchGreeter));
+```
+
+The registration can be done using a component too:
+
+```ts
+export class GreeterComponent implements Component {
+  bindings = [
+    // ...
+    createBindingFromClass(EnglishGreeter),
+    createBindingFromClass(ChineseGreeter),
+  ];
+}
+```
+
+## Configure an extension point
+
+Sometimes it's desirable to make the extension point configurable. Two steps are
+involved to achieve that.
+
+1. Declare an injection for the configuration for your extension point class:
+
+```ts
+export class GreetingService {
+  constructor(
+    // ...
+    private greeters: Getter<Greeter[]>,
+    /**
+     * An extension point should be able to receive its options via dependency
+     * injection.
+     */
+    @configuration() // Sugar for @inject('services.GreetingService.options', {optional: true})
+    private options?: GreeterExtensionPointOptions,
+  ) {}
+}
+```
+
+2. Set configuration for the extension point
+
+```ts
+// Configure the extension point
+app.bind('services.GreetingService.options').to({color: 'blue'});
+```
+
+## Configure an extension
+
+Some extensions also support customization. The approach is similar as how to
+configure an extension point.
+
+1. Declare an injection for the configuration in the extension class
+
+```ts
+export class ChineseGreeter implements Greeter {
+  language = 'zh';
+
+  constructor(
+    /**
+     * Inject the configuration for ChineseGreeter
+     */
+    @inject('greeters.ChineseGreeter.options', {optional: true})
+    private options: ChineseGreeterOptions = {nameFirst: true},
+  ) {}
+}
+```
+
+2. Set configuration for the extension
+
+```ts
+// Configure the ChineseGreeter
+app.bind('greeters.ChineseGreeter.options').to({nameFirst: false});
+```
+
+## Contributions
+
+- [Guidelines](https://github.com/strongloop/loopback-next/blob/master/docs/CONTRIBUTING.md)
+- [Join the team](https://github.com/strongloop/loopback-next/issues/110)
+
+## Tests
+
+Run `npm test` from the root folder.
+
+## Contributors
+
+See
+[all contributors](https://github.com/strongloop/loopback-next/graphs/contributors).
+
+## License
+
+MIT
diff --git a/examples/greeter-extension/greeters.png b/examples/greeter-extension/greeters.png
new file mode 100644
index 000000000000..600633d7940b
Binary files /dev/null and b/examples/greeter-extension/greeters.png differ
diff --git a/examples/greeter-extension/index.d.ts b/examples/greeter-extension/index.d.ts
new file mode 100644
index 000000000000..18078ab5428c
--- /dev/null
+++ b/examples/greeter-extension/index.d.ts
@@ -0,0 +1,6 @@
+// Copyright IBM Corp. 2019. All Rights Reserved.
+// Node module: @loopback/example-greeter-extension
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+export * from './dist';
diff --git a/examples/greeter-extension/index.js b/examples/greeter-extension/index.js
new file mode 100644
index 000000000000..96b109ab9512
--- /dev/null
+++ b/examples/greeter-extension/index.js
@@ -0,0 +1,6 @@
+// Copyright IBM Corp. 2019. All Rights Reserved.
+// Node module: @loopback/example-greeter-extension
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+module.exports = require('./dist');
diff --git a/examples/greeter-extension/index.ts b/examples/greeter-extension/index.ts
new file mode 100644
index 000000000000..1b15e24a91e8
--- /dev/null
+++ b/examples/greeter-extension/index.ts
@@ -0,0 +1,6 @@
+// Copyright IBM Corp. 2019. All Rights Reserved.
+// Node module: @loopback/example-log-extension
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+export * from './src';
diff --git a/examples/greeter-extension/package-lock.json b/examples/greeter-extension/package-lock.json
new file mode 100644
index 000000000000..bd9518b0d28b
--- /dev/null
+++ b/examples/greeter-extension/package-lock.json
@@ -0,0 +1,371 @@
+{
+	"name": "@loopback/example-greeter-extension",
+	"version": "1.0.0-1",
+	"lockfileVersion": 1,
+	"requires": true,
+	"dependencies": {
+		"@types/debug": {
+			"version": "0.0.30",
+			"resolved": "https://registry.npmjs.org/@types/debug/-/debug-0.0.30.tgz",
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+			"dev": true
+		},
+		"@types/node": {
+			"version": "10.12.30",
+			"resolved": "https://registry.npmjs.org/@types/node/-/node-10.12.30.tgz",
+			"integrity": "sha512-nsqTN6zUcm9xtdJiM9OvOJ5EF0kOI8f1Zuug27O/rgtxCRJHGqncSWfCMZUP852dCKPsDsYXGvBhxfRjDBkF5Q==",
+			"dev": true
+		},
+		"ansi-regex": {
+			"version": "2.1.1",
+			"resolved": "https://registry.npmjs.org/ansi-regex/-/ansi-regex-2.1.1.tgz",
+			"integrity": "sha1-w7M6te42DYbg5ijwRorn7yfWVN8=",
+			"dev": true
+		},
+		"ansi-styles": {
+			"version": "3.2.1",
+			"resolved": "https://registry.npmjs.org/ansi-styles/-/ansi-styles-3.2.1.tgz",
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+			"requires": {
+				"color-convert": "^1.9.0"
+			}
+		},
+		"argparse": {
+			"version": "1.0.10",
+			"resolved": "https://registry.npmjs.org/argparse/-/argparse-1.0.10.tgz",
+			"integrity": "sha512-o5Roy6tNG4SL/FOkCAN6RzjiakZS25RLYFrcMttJqbdd8BWrnA+fGz57iN5Pb06pvBGvl5gQ0B48dJlslXvoTg==",
+			"dev": true,
+			"requires": {
+				"sprintf-js": "~1.0.2"
+			}
+		},
+		"babel-code-frame": {
+			"version": "6.26.0",
+			"resolved": "https://registry.npmjs.org/babel-code-frame/-/babel-code-frame-6.26.0.tgz",
+			"integrity": "sha1-Y/1D99weO7fONZR9uP42mj9Yx0s=",
+			"dev": true,
+			"requires": {
+				"chalk": "^1.1.3",
+				"esutils": "^2.0.2",
+				"js-tokens": "^3.0.2"
+			},
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+				"ansi-styles": {
+					"version": "2.2.1",
+					"resolved": "https://registry.npmjs.org/ansi-styles/-/ansi-styles-2.2.1.tgz",
+					"integrity": "sha1-tDLdM1i2NM914eRmQ2gkBTPB3b4=",
+					"dev": true
+				},
+				"chalk": {
+					"version": "1.1.3",
+					"resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+					"integrity": "sha1-qBFcVeSnAv5NFQq9OHKCKn4J/Jg=",
+					"dev": true,
+					"requires": {
+						"ansi-styles": "^2.2.1",
+						"escape-string-regexp": "^1.0.2",
+						"has-ansi": "^2.0.0",
+						"strip-ansi": "^3.0.0",
+						"supports-color": "^2.0.0"
+					}
+				},
+				"supports-color": {
+					"version": "2.0.0",
+					"resolved": "https://registry.npmjs.org/supports-color/-/supports-color-2.0.0.tgz",
+					"integrity": "sha1-U10EXOa2Nj+kARcIRimZXp3zJMc=",
+					"dev": true
+				}
+			}
+		},
+		"balanced-match": {
+			"version": "1.0.0",
+			"resolved": "https://registry.npmjs.org/balanced-match/-/balanced-match-1.0.0.tgz",
+			"integrity": "sha1-ibTRmasr7kneFk6gK4nORi1xt2c=",
+			"dev": true
+		},
+		"brace-expansion": {
+			"version": "1.1.11",
+			"resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.11.tgz",
+			"integrity": "sha512-iCuPHDFgrHX7H2vEI/5xpz07zSHB00TpugqhmYtVmMO6518mCuRMoOYFldEBl0g187ufozdaHgWKcYFb61qGiA==",
+			"dev": true,
+			"requires": {
+				"balanced-match": "^1.0.0",
+				"concat-map": "0.0.1"
+			}
+		},
+		"builtin-modules": {
+			"version": "1.1.1",
+			"resolved": "https://registry.npmjs.org/builtin-modules/-/builtin-modules-1.1.1.tgz",
+			"integrity": "sha1-Jw8HbFpywC9bZaR9+Uxf46J4iS8=",
+			"dev": true
+		},
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+			"dev": true
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+		"wrappy": {
+			"version": "1.0.2",
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+}
diff --git a/examples/greeter-extension/package.json b/examples/greeter-extension/package.json
new file mode 100644
index 000000000000..9aef4590ee80
--- /dev/null
+++ b/examples/greeter-extension/package.json
@@ -0,0 +1,60 @@
+{
+  "name": "@loopback/example-greeter-extension",
+  "version": "1.0.0-1",
+  "description": "An example extension point/extensions for LoopBack 4",
+  "main": "index.js",
+  "engines": {
+    "node": ">=8.9"
+  },
+  "scripts": {
+    "build:apidocs": "lb-apidocs",
+    "build": "lb-tsc es2017 --outDir dist",
+    "build:watch": "lb-tsc es2017 --outDir dist --watch",
+    "clean": "lb-clean *example-greeter-extension-*.tgz dist package api-docs",
+    "lint": "npm run prettier:check && npm run tslint",
+    "lint:fix": "npm run tslint:fix && npm run prettier:fix",
+    "prettier:cli": "lb-prettier \"**/*.ts\" \"**/*.js\"",
+    "prettier:check": "npm run prettier:cli -- -l",
+    "prettier:fix": "npm run prettier:cli -- --write",
+    "tslint": "lb-tslint",
+    "tslint:fix": "npm run tslint -- --fix",
+    "pretest": "npm run clean && npm run build",
+    "test": "lb-mocha \"dist/__tests__/**/*.js\"",
+    "posttest": "npm run lint",
+    "test:dev": "lb-mocha --allow-console-logs dist/__tests__/**/*.js && npm run posttest",
+    "verify": "npm pack && tar xf *example-greeter-extension*.tgz && tree package && npm run clean"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/strongloop/loopback-next.git"
+  },
+  "publishConfig": {
+    "access": "public"
+  },
+  "keywords": [
+    "loopback",
+    "loopback-extension"
+  ],
+  "license": "MIT",
+  "bugs": {
+    "url": "https://github.com/strongloop/loopback-next/issues"
+  },
+  "homepage": "https://github.com/strongloop/loopback-next/tree/master/examples/greeter-extension",
+  "devDependencies": {
+    "@loopback/build": "^1.1.0",
+    "@loopback/testlab": "^1.0.3",
+    "@loopback/tslint-config": "^2.0.0",
+    "@types/debug": "0.0.30",
+    "@types/node": "^10.11.2",
+    "tslint": "^5.12.0",
+    "typescript": "^3.2.2"
+  },
+  "dependencies": {
+    "@loopback/context": "^1.4.0",
+    "@loopback/core": "^1.1.3",
+    "@loopback/openapi-v3": "^1.1.5",
+    "@loopback/rest": "^1.5.1",
+    "chalk": "^2.4.2",
+    "debug": "^4.0.1"
+  }
+}
diff --git a/examples/greeter-extension/src/__tests__/greeter-extension.acceptance.ts b/examples/greeter-extension/src/__tests__/greeter-extension.acceptance.ts
new file mode 100644
index 000000000000..6a86a1d224b3
--- /dev/null
+++ b/examples/greeter-extension/src/__tests__/greeter-extension.acceptance.ts
@@ -0,0 +1,80 @@
+// Copyright IBM Corp. 2019. All Rights Reserved.
+// Node module: @loopback/example-greeter-extension
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+import {Application, bind, createBindingFromClass} from '@loopback/core';
+import {expect} from '@loopback/testlab';
+import chalk from 'chalk';
+import {
+  asGreeter,
+  Greeter,
+  GreeterComponent,
+  GreetingService,
+  GREETING_SERVICE,
+} from '..';
+
+describe('greeter-extension-pont', () => {
+  let app: Application;
+  let greetingService: GreetingService;
+
+  beforeEach(givenAppWithGreeterComponent);
+  beforeEach(findGreetingService);
+
+  it('greets by language', async () => {
+    let msg = await greetingService.greet('en', 'Raymond');
+    expect(msg).to.eql('Hello, Raymond');
+    msg = await greetingService.greet('zh', 'Raymond');
+    expect(msg).to.eql('Raymond，你好！');
+  });
+
+  it('supports options for the extension point', async () => {
+    // Configure the extension point
+    app.bind('services.GreetingService.options').to({color: 'blue'});
+    const _greetingService = await app.get(GREETING_SERVICE);
+    const msg = await _greetingService.greet('en', 'Raymond');
+    expect(msg).to.eql(chalk.keyword('blue')('Hello, Raymond'));
+  });
+
+  it('supports options for extensions', async () => {
+    // Configure the ChineseGreeter
+    app.bind('greeters.ChineseGreeter.options').to({nameFirst: false});
+    const msg = await greetingService.greet('zh', 'Raymond');
+    expect(msg).to.eql('你好，Raymond！');
+  });
+
+  it('honors a newly added/removed greeter binding', async () => {
+    /**
+     * A greeter implementation for French
+     */
+    @bind(asGreeter)
+    class FrenchGreeter implements Greeter {
+      language = 'fr';
+
+      greet(name: string) {
+        return `Bonjour, ${name}`;
+      }
+    }
+    // Add a new greeter for French
+    const binding = createBindingFromClass(FrenchGreeter);
+    app.add(binding);
+
+    let msg = await greetingService.greet('fr', 'Raymond');
+    expect(msg).to.eql('Bonjour, Raymond');
+
+    // Remove the French greeter
+    app.unbind(binding.key);
+    msg = await greetingService.greet('fr', 'Raymond');
+    // It falls back to English
+    expect(msg).to.eql('Hello, Raymond');
+  });
+
+  function givenAppWithGreeterComponent() {
+    app = new Application();
+    app.component(GreeterComponent);
+  }
+
+  async function findGreetingService() {
+    greetingService = await app.get(GREETING_SERVICE);
+  }
+});
diff --git a/examples/greeter-extension/src/component.ts b/examples/greeter-extension/src/component.ts
new file mode 100644
index 000000000000..b5f1381ef5f7
--- /dev/null
+++ b/examples/greeter-extension/src/component.ts
@@ -0,0 +1,25 @@
+// Copyright IBM Corp. 2019. All Rights Reserved.
+// Node module: @loopback/example-greeter-extension
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+import {createBindingFromClass} from '@loopback/context';
+import {Component} from '@loopback/core';
+import {GreetingService} from './greeting-service';
+import {ChineseGreeter} from './greeters/greeter-cn';
+import {EnglishGreeter} from './greeters/greeter-en';
+import {GREETING_SERVICE} from './keys';
+
+/**
+ * Define a component to register the greeter extension point and built-in
+ * extensions
+ */
+export class GreeterComponent implements Component {
+  bindings = [
+    createBindingFromClass(GreetingService, {
+      key: GREETING_SERVICE,
+    }),
+    createBindingFromClass(EnglishGreeter),
+    createBindingFromClass(ChineseGreeter),
+  ];
+}
diff --git a/examples/greeter-extension/src/decorators.ts b/examples/greeter-extension/src/decorators.ts
new file mode 100644
index 000000000000..3cda6cbc137f
--- /dev/null
+++ b/examples/greeter-extension/src/decorators.ts
@@ -0,0 +1,89 @@
+// Copyright IBM Corp. 2019. All Rights Reserved.
+// Node module: @loopback/example-greeter-extension
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+import {
+  ClassDecoratorFactory,
+  ContextView,
+  filterByTag,
+  inject,
+  MetadataInspector,
+} from '@loopback/context';
+
+export const EXTENSION_POINT_NAME = 'extensionPoint.name';
+
+/**
+ * Decorate a class as a named extension point. If the decoration is not
+ * present, the name of the class will be used.
+ *
+ * TODO: to be promoted to `@loopback/core` module.
+ * @param name Name of the extension point
+ */
+export function extensionPoint(name: string) {
+  return ClassDecoratorFactory.createDecorator(EXTENSION_POINT_NAME, {name});
+}
+
+/**
+ * Shortcut to inject extensions for the given extension point.
+ *
+ * TODO: to be promoted to `@loopback/core` module possibly as
+ * `@inject.extensions`.
+ *
+ * @param extensionPoint Name of the extension point. If not supplied, we use
+ * the name from `@extensionPoint` or the class name of the extension point.
+ */
+export function extensions(extensionPointName?: string) {
+  return inject('', {decorator: '@extensions'}, (ctx, injection, session?) => {
+    if (!session) return undefined;
+    // Find the key of the target binding
+    if (!session.currentBinding) return undefined;
+
+    if (!extensionPointName) {
+      let target: Function;
+      if (typeof injection.target === 'function') {
+        // Constructor injection
+        target = injection.target;
+      } else {
+        // Injection on the prototype
+        target = injection.target.constructor;
+      }
+      const meta:
+        | {name: string}
+        | undefined = MetadataInspector.getClassMetadata(
+        EXTENSION_POINT_NAME,
+        target,
+      );
+      extensionPointName =
+        (meta && meta.name) || injection.target.constructor.name;
+    }
+
+    const bindingFilter = filterByTag({extensionPoint: extensionPointName});
+    const view = new ContextView(ctx, bindingFilter);
+    view.open();
+    return view.asGetter(session);
+  });
+}
+
+/**
+ * Shortcut to inject configuration for the target binding. To be promoted
+ * as `@inject.config` in `@loopback/context` module.
+ *
+ * See https://github.com/strongloop/loopback-next/pull/2259
+ */
+export function configuration() {
+  return inject(
+    '',
+    {decorator: '@inject.config', optional: true},
+    (ctx, injection, session?) => {
+      if (!session) return undefined;
+      // Find the key of the target binding
+      if (!session.currentBinding) return undefined;
+      const key = session.currentBinding!.key;
+      return ctx.get(`${key}.options`, {
+        session,
+        optional: injection.metadata && injection.metadata.optional,
+      });
+    },
+  );
+}
diff --git a/examples/greeter-extension/src/greeters/greeter-cn.ts b/examples/greeter-extension/src/greeters/greeter-cn.ts
new file mode 100644
index 000000000000..74d4960ae713
--- /dev/null
+++ b/examples/greeter-extension/src/greeters/greeter-cn.ts
@@ -0,0 +1,38 @@
+// Copyright IBM Corp. 2019. All Rights Reserved.
+// Node module: @loopback/example-greeter-extension
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+import {bind, inject} from '@loopback/context';
+import {asGreeter, Greeter} from '../types';
+
+/**
+ * Options for the Chinese greeter
+ */
+export interface ChineseGreeterOptions {
+  // Name first, default to `true`
+  nameFirst: boolean;
+}
+
+/**
+ * A greeter implementation for Chinese.
+ */
+@bind(asGreeter)
+export class ChineseGreeter implements Greeter {
+  language = 'zh';
+
+  constructor(
+    /**
+     * Inject the configuration for ChineseGreeter
+     */
+    @inject('greeters.ChineseGreeter.options', {optional: true})
+    private options: ChineseGreeterOptions = {nameFirst: true},
+  ) {}
+
+  greet(name: string) {
+    if (this.options && this.options.nameFirst === false) {
+      return `你好，${name}！`;
+    }
+    return `${name}，你好！`;
+  }
+}
diff --git a/examples/greeter-extension/src/greeters/greeter-en.ts b/examples/greeter-extension/src/greeters/greeter-en.ts
new file mode 100644
index 000000000000..47e404bbace8
--- /dev/null
+++ b/examples/greeter-extension/src/greeters/greeter-en.ts
@@ -0,0 +1,19 @@
+// Copyright IBM Corp. 2019. All Rights Reserved.
+// Node module: @loopback/example-greeter-extension
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+import {bind} from '@loopback/context';
+import {asGreeter, Greeter} from '../types';
+
+/**
+ * A greeter implementation for English
+ */
+@bind(asGreeter)
+export class EnglishGreeter implements Greeter {
+  language = 'en';
+
+  greet(name: string) {
+    return `Hello, ${name}`;
+  }
+}
diff --git a/examples/greeter-extension/src/greeting-service.ts b/examples/greeter-extension/src/greeting-service.ts
new file mode 100644
index 000000000000..898b43d89c56
--- /dev/null
+++ b/examples/greeter-extension/src/greeting-service.ts
@@ -0,0 +1,69 @@
+// Copyright IBM Corp. 2019. All Rights Reserved.
+// Node module: @loopback/example-greeter-extension
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+import {Getter} from '@loopback/context';
+import chalk from 'chalk';
+import {configuration, extensionPoint, extensions} from './decorators';
+import {Greeter} from './types';
+
+/**
+ * Options for the greeter extension point
+ */
+export interface GreetingServiceOptions {
+  color: string;
+}
+
+/**
+ * An extension point for greeters that can greet in different languages
+ */
+@extensionPoint('greeter')
+export class GreetingService {
+  constructor(
+    /**
+     * Inject a getter function to fetch greeters (bindings tagged with
+     * 'greeter')
+     */
+    @extensions() // Sugar for @inject.getter(filterByTag({extensionPoint: 'greeter'}))
+    private greeters: Getter<Greeter[]>,
+    /**
+     * An extension point should be able to receive its options via dependency
+     * injection.
+     */
+    @configuration() // Sugar for @inject('services.GreetingService.options', {optional: true})
+    private options?: GreetingServiceOptions,
+  ) {}
+
+  /**
+   * Find a greeter that can speak the given language
+   * @param language Language code for the greeting
+   */
+  async findGreeter(language: string) {
+    // Get the latest list of greeters
+    const greeters = await this.greeters();
+    // Find a greeter that can speak the given language
+    return greeters.find(g => g.language === language);
+  }
+
+  /**
+   * Greet in the given language
+   * @param language Language code
+   * @param name Name
+   */
+  async greet(language: string, name: string): Promise<string> {
+    let greeting: string = '';
+
+    const greeter = await this.findGreeter(language);
+    if (greeter) {
+      greeting = greeter.greet(name);
+    } else {
+      // Fall back to English
+      greeting = `Hello, ${name}`;
+    }
+    if (this.options && this.options.color) {
+      greeting = chalk.keyword(this.options.color)(greeting);
+    }
+    return greeting;
+  }
+}
diff --git a/examples/greeter-extension/src/index.ts b/examples/greeter-extension/src/index.ts
new file mode 100644
index 000000000000..3014eb83dd43
--- /dev/null
+++ b/examples/greeter-extension/src/index.ts
@@ -0,0 +1,9 @@
+// Copyright IBM Corp. 2019. All Rights Reserved.
+// Node module: @loopback/example-log-extension
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+export * from './component';
+export * from './greeting-service';
+export * from './keys';
+export * from './types';
diff --git a/examples/greeter-extension/src/keys.ts b/examples/greeter-extension/src/keys.ts
new file mode 100644
index 000000000000..2a02ed0e9957
--- /dev/null
+++ b/examples/greeter-extension/src/keys.ts
@@ -0,0 +1,14 @@
+// Copyright IBM Corp. 2019. All Rights Reserved.
+// Node module: @loopback/example-log-extension
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+import {BindingKey} from '@loopback/core';
+import {GreetingService} from './greeting-service';
+
+/**
+ * Strongly-typed binding key for GreetingService
+ */
+export const GREETING_SERVICE = BindingKey.create<GreetingService>(
+  'services.GreetingService',
+);
diff --git a/examples/greeter-extension/src/types.ts b/examples/greeter-extension/src/types.ts
new file mode 100644
index 000000000000..c20e8843c686
--- /dev/null
+++ b/examples/greeter-extension/src/types.ts
@@ -0,0 +1,33 @@
+// Copyright IBM Corp. 2019. All Rights Reserved.
+// Node module: @loopback/example-greeter-extension
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+import {BindingScope, BindingTemplate} from '@loopback/context';
+
+/**
+ * Typically an extension point defines an interface as the contract for
+ * extensions to implement
+ */
+export interface Greeter {
+  language: string;
+  greet(name: string): string;
+}
+
+/**
+ * A factory function to create binding template for extensions of the given
+ * extension point
+ * @param extensionPoint Name/id of the extension point
+ */
+export function extensionFor(extensionPoint: string): BindingTemplate {
+  return binding =>
+    binding.inScope(BindingScope.SINGLETON).tag({extensionPoint});
+}
+
+/**
+ * A binding template for greeter extensions
+ */
+export const asGreeter: BindingTemplate = binding => {
+  extensionFor('greeter')(binding);
+  binding.tag({namespace: 'greeters'});
+};
diff --git a/examples/greeter-extension/tsconfig.build.json b/examples/greeter-extension/tsconfig.build.json
new file mode 100644
index 000000000000..6e15e4be4f6f
--- /dev/null
+++ b/examples/greeter-extension/tsconfig.build.json
@@ -0,0 +1,8 @@
+{
+  "$schema": "http://json.schemastore.org/tsconfig",
+  "extends": "@loopback/build/config/tsconfig.common.json",
+  "compilerOptions": {
+    "rootDir": "src"
+  },
+  "include": ["src"]
+}
diff --git a/examples/greeter-extension/tslint.build.json b/examples/greeter-extension/tslint.build.json
new file mode 100644
index 000000000000..121b8adb21a3
--- /dev/null
+++ b/examples/greeter-extension/tslint.build.json
@@ -0,0 +1,4 @@
+{
+  "$schema": "http://json.schemastore.org/tslint",
+  "extends": ["@loopback/tslint-config/tslint.build.json"]
+}
diff --git a/examples/greeter-extension/tslint.json b/examples/greeter-extension/tslint.json
new file mode 100644
index 000000000000..2bb931e66a64
--- /dev/null
+++ b/examples/greeter-extension/tslint.json
@@ -0,0 +1,4 @@
+{
+  "$schema": "http://json.schemastore.org/tslint",
+  "extends": ["@loopback/tslint-config/tslint.common.json"]
+}
diff --git a/greenkeeper.json b/greenkeeper.json
index 158cf7ba1118..90726f094cf9 100644
--- a/greenkeeper.json
+++ b/greenkeeper.json
@@ -6,6 +6,7 @@
         "benchmark/package.json",
         "docs/package.json",
         "examples/express-composition/package.json",
+        "examples/greeter-extension/package.json",
         "examples/hello-world/package.json",
         "examples/log-extension/package.json",
         "examples/rpc-server/package.json",