diff --git a/composer.json b/composer.json
index d14d0b4..34cd9b3 100644
--- a/composer.json
+++ b/composer.json
@@ -11,7 +11,8 @@
     "require": {
         "php": "^7.4",
         "slim/slim": "^4.5",
-        "slim/psr7": "^1.1"
+        "slim/psr7": "^1.1",
+        "php-di/php-di": "^6.2"
     },
     "require-dev": {
         "phpunit/phpunit": "^9"
diff --git a/composer.lock b/composer.lock
index 7a2270e..8ded0f0 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "c94e0dc94538087f6c99d168389da841",
+    "content-hash": "c9b48ebdf86b04852bf99bd1932d57e8",
     "packages": [
         {
             "name": "fig/http-message-util",
@@ -104,6 +104,219 @@
             ],
             "time": "2018-02-13T20:26:39+00:00"
         },
+        {
+            "name": "opis/closure",
+            "version": "3.5.5",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/opis/closure.git",
+                "reference": "dec9fc5ecfca93f45cd6121f8e6f14457dff372c"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/opis/closure/zipball/dec9fc5ecfca93f45cd6121f8e6f14457dff372c",
+                "reference": "dec9fc5ecfca93f45cd6121f8e6f14457dff372c",
+                "shasum": ""
+            },
+            "require": {
+                "php": "^5.4 || ^7.0"
+            },
+            "require-dev": {
+                "jeremeamia/superclosure": "^2.0",
+                "phpunit/phpunit": "^4.0 || ^5.0 || ^6.0 || ^7.0"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "3.5.x-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Opis\\Closure\\": "src/"
+                },
+                "files": [
+                    "functions.php"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Marius Sarca",
+                    "email": "marius.sarca@gmail.com"
+                },
+                {
+                    "name": "Sorin Sarca",
+                    "email": "sarca_sorin@hotmail.com"
+                }
+            ],
+            "description": "A library that can be used to serialize closures (anonymous functions) and arbitrary objects.",
+            "homepage": "https://opis.io/closure",
+            "keywords": [
+                "anonymous functions",
+                "closure",
+                "function",
+                "serializable",
+                "serialization",
+                "serialize"
+            ],
+            "time": "2020-06-17T14:59:55+00:00"
+        },
+        {
+            "name": "php-di/invoker",
+            "version": "2.0.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/PHP-DI/Invoker.git",
+                "reference": "540c27c86f663e20fe39a24cd72fa76cdb21d41a"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/PHP-DI/Invoker/zipball/540c27c86f663e20fe39a24cd72fa76cdb21d41a",
+                "reference": "540c27c86f663e20fe39a24cd72fa76cdb21d41a",
+                "shasum": ""
+            },
+            "require": {
+                "psr/container": "~1.0"
+            },
+            "require-dev": {
+                "athletic/athletic": "~0.1.8",
+                "phpunit/phpunit": "~4.5"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "Invoker\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "description": "Generic and extensible callable invoker",
+            "homepage": "https://github.com/PHP-DI/Invoker",
+            "keywords": [
+                "callable",
+                "dependency",
+                "dependency-injection",
+                "injection",
+                "invoke",
+                "invoker"
+            ],
+            "time": "2017-03-20T19:28:22+00:00"
+        },
+        {
+            "name": "php-di/php-di",
+            "version": "6.2.1",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/PHP-DI/PHP-DI.git",
+                "reference": "6875fe557c244b3830862c072c7719ca4ac2efe4"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/PHP-DI/PHP-DI/zipball/6875fe557c244b3830862c072c7719ca4ac2efe4",
+                "reference": "6875fe557c244b3830862c072c7719ca4ac2efe4",
+                "shasum": ""
+            },
+            "require": {
+                "opis/closure": "^3.5.5",
+                "php": ">=7.2.0",
+                "php-di/invoker": "^2.0",
+                "php-di/phpdoc-reader": "^2.0.1",
+                "psr/container": "^1.0"
+            },
+            "provide": {
+                "psr/container-implementation": "^1.0"
+            },
+            "require-dev": {
+                "doctrine/annotations": "~1.2",
+                "friendsofphp/php-cs-fixer": "^2.4",
+                "mnapoli/phpunit-easymock": "^1.2",
+                "ocramius/proxy-manager": "~2.0.2",
+                "phpstan/phpstan": "^0.12",
+                "phpunit/phpunit": "^8.5"
+            },
+            "suggest": {
+                "doctrine/annotations": "Install it if you want to use annotations (version ~1.2)",
+                "ocramius/proxy-manager": "Install it if you want to use lazy injection (version ~2.0)"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "DI\\": "src/"
+                },
+                "files": [
+                    "src/functions.php"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "description": "The dependency injection container for humans",
+            "homepage": "https://php-di.org/",
+            "keywords": [
+                "PSR-11",
+                "container",
+                "container-interop",
+                "dependency injection",
+                "di",
+                "ioc",
+                "psr11"
+            ],
+            "funding": [
+                {
+                    "url": "https://github.com/mnapoli",
+                    "type": "github"
+                },
+                {
+                    "url": "https://tidelift.com/funding/github/packagist/php-di/php-di",
+                    "type": "tidelift"
+                }
+            ],
+            "time": "2020-06-18T09:54:32+00:00"
+        },
+        {
+            "name": "php-di/phpdoc-reader",
+            "version": "2.1.1",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/PHP-DI/PhpDocReader.git",
+                "reference": "15678f7451c020226807f520efb867ad26fbbfcf"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/PHP-DI/PhpDocReader/zipball/15678f7451c020226807f520efb867ad26fbbfcf",
+                "reference": "15678f7451c020226807f520efb867ad26fbbfcf",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.4.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "~4.6"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "PhpDocReader\\": "src/PhpDocReader"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "description": "PhpDocReader parses @var and @param values in PHP docblocks (supports namespaced class names with the same resolution rules as PHP)",
+            "keywords": [
+                "phpdoc",
+                "reflection"
+            ],
+            "time": "2019-09-26T11:24:58+00:00"
+        },
         {
             "name": "psr/container",
             "version": "1.0.0",
diff --git a/public/index.php b/public/index.php
index 711e3d1..e5121cd 100644
--- a/public/index.php
+++ b/public/index.php
@@ -3,18 +3,13 @@ declare(strict_types=1);
 
 require_once __DIR__ . '/../vendor/autoload.php';
 
-use Psr\Http\Message\ResponseInterface as Response;
-use Psr\Http\Message\ServerRequestInterface as Request;
+use NoteCat\Dependencies;
+use NoteCat\Routes;
 use Slim\Factory\AppFactory;
 
-use NoteCat\HelloWorld;
+$container = Dependencies::createContainer();
+$app = AppFactory::createFromContainer($container);
 
-$app = AppFactory::create();
-
-$app->get('/', function (Request $request, Response $response, $args) {
-    $hello = new HelloWorld();
-    $response->getBody()->write('<b>' . $hello->getHello() . "</b>\n");
-    return $response;
-});
+Routes::setRoutes($app);
 
 $app->run();
diff --git a/src/Dependencies.php b/src/Dependencies.php
new file mode 100644
index 0000000..b0a6172
--- /dev/null
+++ b/src/Dependencies.php
@@ -0,0 +1,29 @@
+<?php
+declare(strict_types=1);
+
+namespace NoteCat;
+
+use DI\Container;
+use Psr\Container\ContainerInterface;
+
+class Dependencies
+{
+    public static function createContainer(): Container
+    {
+        $container = new Container();
+
+        // Controllers
+        $container->set(HelloWorldController::class, function (ContainerInterface $c) {
+            return new HelloWorldController(
+                $c->get(HelloWorld::class)
+            );
+        });
+
+        // Services
+        $container->set(HelloWorld::class, function () {
+            return new HelloWorld();
+        });
+
+        return $container;
+    }
+}
diff --git a/src/HelloWorldController.php b/src/HelloWorldController.php
new file mode 100644
index 0000000..b98ba33
--- /dev/null
+++ b/src/HelloWorldController.php
@@ -0,0 +1,23 @@
+<?php
+declare(strict_types=1);
+
+namespace NoteCat;
+
+use Psr\Http\Message\ResponseInterface as Response;
+use Psr\Http\Message\ServerRequestInterface as Request;
+
+class HelloWorldController
+{
+    private HelloWorld $hello;
+
+    public function __construct(HelloWorld $hello)
+    {
+        $this->hello = $hello;
+    }
+
+    public function hello(Request $request, Response $response): Response
+    {
+        $response->getBody()->write('<b>' . $this->hello->getHello() . "</b>\n");
+        return $response;
+    }
+}
diff --git a/src/Routes.php b/src/Routes.php
new file mode 100644
index 0000000..d47f2c6
--- /dev/null
+++ b/src/Routes.php
@@ -0,0 +1,15 @@
+<?php
+declare(strict_types=1);
+
+namespace NoteCat;
+
+use NoteCat\HelloWorldController;
+use Slim\App;
+
+class Routes
+{
+    public static function setRoutes(App $app): void
+    {
+        $app->get('/', HelloWorldController::class . ':hello');
+    }
+}