diff --git a/.gitignore b/.gitignore
index 17e07e7..13b7173 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,3 +4,4 @@ bin/
 !bin/dcv
 !bin/entrypoint.sh
 .cache/
+.php_cs.cache
diff --git a/.php_cs b/.php_cs
index 29fd36a..ed09307 100644
--- a/.php_cs
+++ b/.php_cs
@@ -1,12 +1,15 @@
 <?php
 
-$finder = Symfony\CS\Finder\DefaultFinder::create()
-    ->exclude('somedir')
+use PhpCsFixer as CS;
+
+$finder = CS\Finder::create()
     ->in(__DIR__.DIRECTORY_SEPARATOR.'src')
     ->in(__DIR__.DIRECTORY_SEPARATOR.'spec')
 ;
 
-return Symfony\CS\Config\Config::create()
-    ->level(Symfony\CS\FixerInterface::SYMFONY_LEVEL)
-    ->finder($finder)
+return CS\Config::create()
+    ->setRules([
+        '@Symfony' => true,
+    ])
+    ->setFinder($finder)
 ;
diff --git a/.travis.yml b/.travis.yml
index f31ce34..887534f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -8,12 +8,14 @@ services:
 php:
     - 7.0
     - 7.1
+    - 7.2
     - nightly
 
 env:
     matrix:
         - COMPOSERFLAGS=
         - COMPOSERFLAGS=--prefer-lowest
+        - COMPOSERFLAGS=--prefer-stable
 
     global:
         # DOCKER_EMAIL
@@ -29,6 +31,8 @@ matrix:
           env: COMPOSERFLAGS=
         - php: 7.1
           env: COMPOSERFLAGS=--prefer-lowest
+        - php: 7.2
+          env: COMPOSERFLAGS=--prefer-lowest
         - php: nightly
           env: COMPOSERFLAGS=--prefer-lowest
     allow_failures:
diff --git a/composer.json b/composer.json
index 1b6589f..03e7e03 100644
--- a/composer.json
+++ b/composer.json
@@ -2,14 +2,15 @@
     "name": "pmsipilot/docker-compose-viz",
     "description": "Docker compose graph visualization",
     "require": {
-        "symfony/yaml": "^3.1 || ^4@dev",
+        "php": "^7",
+        "symfony/yaml": "^3.1 || ^4",
         "symfony/console": "^3.1",
         "clue/graph": "^0.9",
         "graphp/graphviz": "^0.2"
     },
     "require-dev": {
         "crysalead/kahlan": "^2.5.4",
-        "friendsofphp/php-cs-fixer": "^1.11"
+        "friendsofphp/php-cs-fixer": "^2"
     },
     "license": "MIT",
     "authors": [
diff --git a/composer.lock b/composer.lock
index a6bbcb3..1d7b126 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,8 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#composer-lock-the-lock-file",
         "This file is @generated automatically"
     ],
-    "hash": "0d62100317a058684fbda02b5b1a8b28",
-    "content-hash": "2a9cfe4bb29738f0495cc645b6ed6c65",
+    "content-hash": "e5370b9d4f890699543b1dbd6ba801de",
     "packages": [
         {
             "name": "clue/graph",
@@ -50,7 +49,7 @@
                 "network",
                 "vertex"
             ],
-            "time": "2015-03-07 18:11:31"
+            "time": "2015-03-07T18:11:31+00:00"
         },
         {
             "name": "graphp/algorithms",
@@ -100,7 +99,7 @@
                 "prim",
                 "shortest path"
             ],
-            "time": "2015-03-08 10:12:01"
+            "time": "2015-03-08T10:12:01+00:00"
         },
         {
             "name": "graphp/graphviz",
@@ -142,7 +141,7 @@
                 "graph image",
                 "graphviz"
             ],
-            "time": "2015-03-08 10:30:28"
+            "time": "2015-03-08T10:30:28+00:00"
         },
         {
             "name": "psr/log",
@@ -189,48 +188,49 @@
                 "psr",
                 "psr-3"
             ],
-            "time": "2016-10-10 12:19:37"
+            "time": "2016-10-10T12:19:37+00:00"
         },
         {
             "name": "symfony/console",
-            "version": "v3.3.0",
+            "version": "v3.4.3",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/console.git",
-                "reference": "c80e63f3f5e3a331bfc25e6e9332b10422eb9b05"
+                "reference": "8394c8ef121949e8f858f13bc1e34f05169e4e7d"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/console/zipball/c80e63f3f5e3a331bfc25e6e9332b10422eb9b05",
-                "reference": "c80e63f3f5e3a331bfc25e6e9332b10422eb9b05",
+                "url": "https://api.github.com/repos/symfony/console/zipball/8394c8ef121949e8f858f13bc1e34f05169e4e7d",
+                "reference": "8394c8ef121949e8f858f13bc1e34f05169e4e7d",
                 "shasum": ""
             },
             "require": {
-                "php": ">=5.5.9",
-                "symfony/debug": "~2.8|~3.0",
+                "php": "^5.5.9|>=7.0.8",
+                "symfony/debug": "~2.8|~3.0|~4.0",
                 "symfony/polyfill-mbstring": "~1.0"
             },
             "conflict": {
-                "symfony/dependency-injection": "<3.3"
+                "symfony/dependency-injection": "<3.4",
+                "symfony/process": "<3.3"
             },
             "require-dev": {
                 "psr/log": "~1.0",
-                "symfony/dependency-injection": "~3.3",
-                "symfony/event-dispatcher": "~2.8|~3.0",
-                "symfony/filesystem": "~2.8|~3.0",
-                "symfony/http-kernel": "~2.8|~3.0",
-                "symfony/process": "~2.8|~3.0"
+                "symfony/config": "~3.3|~4.0",
+                "symfony/dependency-injection": "~3.4|~4.0",
+                "symfony/event-dispatcher": "~2.8|~3.0|~4.0",
+                "symfony/lock": "~3.4|~4.0",
+                "symfony/process": "~3.3|~4.0"
             },
             "suggest": {
                 "psr/log": "For using the console logger",
                 "symfony/event-dispatcher": "",
-                "symfony/filesystem": "",
+                "symfony/lock": "",
                 "symfony/process": ""
             },
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "3.3-dev"
+                    "dev-master": "3.4-dev"
                 }
             },
             "autoload": {
@@ -257,36 +257,36 @@
             ],
             "description": "Symfony Console Component",
             "homepage": "https://symfony.com",
-            "time": "2017-05-28 14:08:56"
+            "time": "2018-01-03T07:37:34+00:00"
         },
         {
             "name": "symfony/debug",
-            "version": "v3.3.0",
+            "version": "v4.0.3",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/debug.git",
-                "reference": "ef5f19a7a68075a0bd05969a329ead3b0776fb7a"
+                "reference": "9ae4223a661b56a9abdce144de4886cca37f198f"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/debug/zipball/ef5f19a7a68075a0bd05969a329ead3b0776fb7a",
-                "reference": "ef5f19a7a68075a0bd05969a329ead3b0776fb7a",
+                "url": "https://api.github.com/repos/symfony/debug/zipball/9ae4223a661b56a9abdce144de4886cca37f198f",
+                "reference": "9ae4223a661b56a9abdce144de4886cca37f198f",
                 "shasum": ""
             },
             "require": {
-                "php": ">=5.5.9",
+                "php": "^7.1.3",
                 "psr/log": "~1.0"
             },
             "conflict": {
-                "symfony/http-kernel": ">=2.3,<2.3.24|~2.4.0|>=2.5,<2.5.9|>=2.6,<2.6.2"
+                "symfony/http-kernel": "<3.4"
             },
             "require-dev": {
-                "symfony/http-kernel": "~2.8|~3.0"
+                "symfony/http-kernel": "~3.4|~4.0"
             },
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "3.3-dev"
+                    "dev-master": "4.0-dev"
                 }
             },
             "autoload": {
@@ -313,20 +313,20 @@
             ],
             "description": "Symfony Debug Component",
             "homepage": "https://symfony.com",
-            "time": "2017-05-27 16:02:27"
+            "time": "2018-01-03T17:15:19+00:00"
         },
         {
             "name": "symfony/polyfill-mbstring",
-            "version": "v1.3.0",
+            "version": "v1.6.0",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/polyfill-mbstring.git",
-                "reference": "e79d363049d1c2128f133a2667e4f4190904f7f4"
+                "reference": "2ec8b39c38cb16674bbf3fea2b6ce5bf117e1296"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/polyfill-mbstring/zipball/e79d363049d1c2128f133a2667e4f4190904f7f4",
-                "reference": "e79d363049d1c2128f133a2667e4f4190904f7f4",
+                "url": "https://api.github.com/repos/symfony/polyfill-mbstring/zipball/2ec8b39c38cb16674bbf3fea2b6ce5bf117e1296",
+                "reference": "2ec8b39c38cb16674bbf3fea2b6ce5bf117e1296",
                 "shasum": ""
             },
             "require": {
@@ -338,7 +338,7 @@
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "1.3-dev"
+                    "dev-master": "1.6-dev"
                 }
             },
             "autoload": {
@@ -372,25 +372,28 @@
                 "portable",
                 "shim"
             ],
-            "time": "2016-11-14 01:06:16"
+            "time": "2017-10-11T12:05:26+00:00"
         },
         {
             "name": "symfony/yaml",
-            "version": "dev-master",
+            "version": "v4.0.3",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/yaml.git",
-                "reference": "5037d791db10d60b23385b64374ee9f29b945945"
+                "reference": "b84f646b9490d2101e2c25ddeec77ceefbda2eee"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/yaml/zipball/5037d791db10d60b23385b64374ee9f29b945945",
-                "reference": "5037d791db10d60b23385b64374ee9f29b945945",
+                "url": "https://api.github.com/repos/symfony/yaml/zipball/b84f646b9490d2101e2c25ddeec77ceefbda2eee",
+                "reference": "b84f646b9490d2101e2c25ddeec77ceefbda2eee",
                 "shasum": ""
             },
             "require": {
                 "php": "^7.1.3"
             },
+            "conflict": {
+                "symfony/console": "<3.4"
+            },
             "require-dev": {
                 "symfony/console": "~3.4|~4.0"
             },
@@ -427,10 +430,72 @@
             ],
             "description": "Symfony Yaml Component",
             "homepage": "https://symfony.com",
-            "time": "2017-05-28 11:01:50"
+            "time": "2018-01-03T07:38:00+00:00"
         }
     ],
     "packages-dev": [
+        {
+            "name": "composer/semver",
+            "version": "1.4.2",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/composer/semver.git",
+                "reference": "c7cb9a2095a074d131b65a8a0cd294479d785573"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/composer/semver/zipball/c7cb9a2095a074d131b65a8a0cd294479d785573",
+                "reference": "c7cb9a2095a074d131b65a8a0cd294479d785573",
+                "shasum": ""
+            },
+            "require": {
+                "php": "^5.3.2 || ^7.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "^4.5 || ^5.0.5",
+                "phpunit/phpunit-mock-objects": "2.3.0 || ^3.0"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "1.x-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Composer\\Semver\\": "src"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Nils Adermann",
+                    "email": "naderman@naderman.de",
+                    "homepage": "http://www.naderman.de"
+                },
+                {
+                    "name": "Jordi Boggiano",
+                    "email": "j.boggiano@seld.be",
+                    "homepage": "http://seld.be"
+                },
+                {
+                    "name": "Rob Bast",
+                    "email": "rob.bast@gmail.com",
+                    "homepage": "http://robbast.nl"
+                }
+            ],
+            "description": "Semver library that offers utilities, version constraint parsing and validation.",
+            "keywords": [
+                "semantic",
+                "semver",
+                "validation",
+                "versioning"
+            ],
+            "time": "2016-08-30T16:08:34+00:00"
+        },
         {
             "name": "crysalead/kahlan",
             "version": "2.5.6",
@@ -481,48 +546,201 @@
                 "unit test"
             ],
             "abandoned": "kahlan/kahlan",
-            "time": "2016-08-18 13:29:17"
+            "time": "2016-08-18T13:29:17+00:00"
         },
         {
-            "name": "friendsofphp/php-cs-fixer",
-            "version": "v1.13.1",
+            "name": "doctrine/annotations",
+            "version": "v1.6.0",
             "source": {
                 "type": "git",
-                "url": "https://github.com/FriendsOfPHP/PHP-CS-Fixer.git",
-                "reference": "0ea4f7ed06ca55da1d8fc45da26ff87f261c4088"
+                "url": "https://github.com/doctrine/annotations.git",
+                "reference": "c7f2050c68a9ab0bdb0f98567ec08d80ea7d24d5"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/FriendsOfPHP/PHP-CS-Fixer/zipball/0ea4f7ed06ca55da1d8fc45da26ff87f261c4088",
-                "reference": "0ea4f7ed06ca55da1d8fc45da26ff87f261c4088",
+                "url": "https://api.github.com/repos/doctrine/annotations/zipball/c7f2050c68a9ab0bdb0f98567ec08d80ea7d24d5",
+                "reference": "c7f2050c68a9ab0bdb0f98567ec08d80ea7d24d5",
                 "shasum": ""
             },
             "require": {
-                "ext-tokenizer": "*",
-                "php": "^5.3.6 || >=7.0 <7.2",
-                "sebastian/diff": "^1.1",
-                "symfony/console": "^2.3 || ^3.0",
-                "symfony/event-dispatcher": "^2.1 || ^3.0",
-                "symfony/filesystem": "^2.1 || ^3.0",
-                "symfony/finder": "^2.1 || ^3.0",
-                "symfony/process": "^2.3 || ^3.0",
-                "symfony/stopwatch": "^2.5 || ^3.0"
-            },
-            "conflict": {
-                "hhvm": "<3.9"
+                "doctrine/lexer": "1.*",
+                "php": "^7.1"
             },
             "require-dev": {
-                "phpunit/phpunit": "^4.5|^5",
-                "satooshi/php-coveralls": "^1.0"
+                "doctrine/cache": "1.*",
+                "phpunit/phpunit": "^6.4"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "1.6.x-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Doctrine\\Common\\Annotations\\": "lib/Doctrine/Common/Annotations"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Roman Borschel",
+                    "email": "roman@code-factory.org"
+                },
+                {
+                    "name": "Benjamin Eberlei",
+                    "email": "kontakt@beberlei.de"
+                },
+                {
+                    "name": "Guilherme Blanco",
+                    "email": "guilhermeblanco@gmail.com"
+                },
+                {
+                    "name": "Jonathan Wage",
+                    "email": "jonwage@gmail.com"
+                },
+                {
+                    "name": "Johannes Schmitt",
+                    "email": "schmittjoh@gmail.com"
+                }
+            ],
+            "description": "Docblock Annotations Parser",
+            "homepage": "http://www.doctrine-project.org",
+            "keywords": [
+                "annotations",
+                "docblock",
+                "parser"
+            ],
+            "time": "2017-12-06T07:11:42+00:00"
+        },
+        {
+            "name": "doctrine/lexer",
+            "version": "v1.0.1",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/doctrine/lexer.git",
+                "reference": "83893c552fd2045dd78aef794c31e694c37c0b8c"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/doctrine/lexer/zipball/83893c552fd2045dd78aef794c31e694c37c0b8c",
+                "reference": "83893c552fd2045dd78aef794c31e694c37c0b8c",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.3.2"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "1.0.x-dev"
+                }
+            },
+            "autoload": {
+                "psr-0": {
+                    "Doctrine\\Common\\Lexer\\": "lib/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Roman Borschel",
+                    "email": "roman@code-factory.org"
+                },
+                {
+                    "name": "Guilherme Blanco",
+                    "email": "guilhermeblanco@gmail.com"
+                },
+                {
+                    "name": "Johannes Schmitt",
+                    "email": "schmittjoh@gmail.com"
+                }
+            ],
+            "description": "Base library for a lexer that can be used in Top-Down, Recursive Descent Parsers.",
+            "homepage": "http://www.doctrine-project.org",
+            "keywords": [
+                "lexer",
+                "parser"
+            ],
+            "time": "2014-09-09T13:34:57+00:00"
+        },
+        {
+            "name": "friendsofphp/php-cs-fixer",
+            "version": "v2.10.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/FriendsOfPHP/PHP-CS-Fixer.git",
+                "reference": "513a3765b56dd029175f9f32995566657ee89dda"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/FriendsOfPHP/PHP-CS-Fixer/zipball/513a3765b56dd029175f9f32995566657ee89dda",
+                "reference": "513a3765b56dd029175f9f32995566657ee89dda",
+                "shasum": ""
+            },
+            "require": {
+                "composer/semver": "^1.4",
+                "doctrine/annotations": "^1.2",
+                "ext-json": "*",
+                "ext-tokenizer": "*",
+                "gecko-packages/gecko-php-unit": "^2.0 || ^3.0",
+                "php": "^5.6 || >=7.0 <7.3",
+                "php-cs-fixer/diff": "^1.2",
+                "symfony/console": "^3.2 || ^4.0",
+                "symfony/event-dispatcher": "^3.0 || ^4.0",
+                "symfony/filesystem": "^3.0 || ^4.0",
+                "symfony/finder": "^3.0 || ^4.0",
+                "symfony/options-resolver": "^3.0 || ^4.0",
+                "symfony/polyfill-php70": "^1.0",
+                "symfony/polyfill-php72": "^1.4",
+                "symfony/process": "^3.0 || ^4.0",
+                "symfony/stopwatch": "^3.0 || ^4.0"
+            },
+            "conflict": {
+                "hhvm": "*"
+            },
+            "require-dev": {
+                "johnkary/phpunit-speedtrap": "^1.1 || ^2.0@dev",
+                "justinrainbow/json-schema": "^5.0",
+                "keradus/cli-executor": "^1.0",
+                "mikey179/vfsstream": "^1.6",
+                "php-coveralls/php-coveralls": "^2.0",
+                "php-cs-fixer/accessible-object": "^1.0",
+                "phpunit/phpunit": "^5.7.23 || ^6.4.3",
+                "phpunitgoodpractices/traits": "^1.0",
+                "symfony/phpunit-bridge": "^3.2.2 || ^4.0"
+            },
+            "suggest": {
+                "ext-mbstring": "For handling non-UTF8 characters in cache signature.",
+                "symfony/polyfill-mbstring": "When enabling `ext-mbstring` is not possible."
             },
             "bin": [
                 "php-cs-fixer"
             ],
             "type": "application",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "2.10-dev"
+                }
+            },
             "autoload": {
                 "psr-4": {
-                    "Symfony\\CS\\": "Symfony/CS/"
-                }
+                    "PhpCsFixer\\": "src/"
+                },
+                "classmap": [
+                    "tests/Test/AbstractFixerTestCase.php",
+                    "tests/Test/AbstractIntegrationTestCase.php",
+                    "tests/Test/Assert/AssertTokensTrait.php",
+                    "tests/Test/IntegrationCase.php",
+                    "tests/Test/IntegrationCaseFactory.php",
+                    "tests/TestCase.php"
+                ]
             },
             "notification-url": "https://packagist.org/downloads/",
             "license": [
@@ -539,43 +757,133 @@
                 }
             ],
             "description": "A tool to automatically fix PHP code style",
-            "time": "2016-12-01 00:05:05"
+            "time": "2018-01-10T17:16:15+00:00"
         },
         {
-            "name": "sebastian/diff",
-            "version": "1.4.3",
+            "name": "gecko-packages/gecko-php-unit",
+            "version": "v3.0",
             "source": {
                 "type": "git",
-                "url": "https://github.com/sebastianbergmann/diff.git",
-                "reference": "7f066a26a962dbe58ddea9f72a4e82874a3975a4"
+                "url": "https://github.com/GeckoPackages/GeckoPHPUnit.git",
+                "reference": "6a866551dffc2154c1b091bae3a7877d39c25ca3"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/sebastianbergmann/diff/zipball/7f066a26a962dbe58ddea9f72a4e82874a3975a4",
-                "reference": "7f066a26a962dbe58ddea9f72a4e82874a3975a4",
+                "url": "https://api.github.com/repos/GeckoPackages/GeckoPHPUnit/zipball/6a866551dffc2154c1b091bae3a7877d39c25ca3",
+                "reference": "6a866551dffc2154c1b091bae3a7877d39c25ca3",
                 "shasum": ""
             },
             "require": {
-                "php": "^5.3.3 || ^7.0"
+                "php": "^7.0"
             },
             "require-dev": {
-                "phpunit/phpunit": "^4.8.35 || ^5.7 || ^6.0"
+                "phpunit/phpunit": "^6.0"
+            },
+            "suggest": {
+                "ext-dom": "When testing with xml.",
+                "ext-libxml": "When testing with xml.",
+                "phpunit/phpunit": "This is an extension for it so make sure you have it some way."
             },
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "1.4-dev"
+                    "dev-master": "3.0-dev"
                 }
             },
+            "autoload": {
+                "psr-4": {
+                    "GeckoPackages\\PHPUnit\\": "src/PHPUnit"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "description": "Additional PHPUnit asserts and constraints.",
+            "homepage": "https://github.com/GeckoPackages",
+            "keywords": [
+                "extension",
+                "filesystem",
+                "phpunit"
+            ],
+            "time": "2017-08-23T07:46:41+00:00"
+        },
+        {
+            "name": "paragonie/random_compat",
+            "version": "v2.0.11",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/paragonie/random_compat.git",
+                "reference": "5da4d3c796c275c55f057af5a643ae297d96b4d8"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/paragonie/random_compat/zipball/5da4d3c796c275c55f057af5a643ae297d96b4d8",
+                "reference": "5da4d3c796c275c55f057af5a643ae297d96b4d8",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.2.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "4.*|5.*"
+            },
+            "suggest": {
+                "ext-libsodium": "Provides a modern crypto API that can be used to generate random bytes."
+            },
+            "type": "library",
+            "autoload": {
+                "files": [
+                    "lib/random.php"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Paragon Initiative Enterprises",
+                    "email": "security@paragonie.com",
+                    "homepage": "https://paragonie.com"
+                }
+            ],
+            "description": "PHP 5.x polyfill for random_bytes() and random_int() from PHP 7",
+            "keywords": [
+                "csprng",
+                "pseudorandom",
+                "random"
+            ],
+            "time": "2017-09-27T21:40:39+00:00"
+        },
+        {
+            "name": "php-cs-fixer/diff",
+            "version": "v1.2.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/PHP-CS-Fixer/diff.git",
+                "reference": "f0ef6133d674137e902fdf8a6f2e8e97e14a087b"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/PHP-CS-Fixer/diff/zipball/f0ef6133d674137e902fdf8a6f2e8e97e14a087b",
+                "reference": "f0ef6133d674137e902fdf8a6f2e8e97e14a087b",
+                "shasum": ""
+            },
+            "require": {
+                "php": "^5.6 || ^7.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "^4.8.35 || ^5.4.3",
+                "symfony/process": "^3.3"
+            },
+            "type": "library",
             "autoload": {
                 "classmap": [
                     "src/"
                 ]
             },
             "notification-url": "https://packagist.org/downloads/",
-            "license": [
-                "BSD-3-Clause"
-            ],
             "authors": [
                 {
                     "name": "Kore Nordmann",
@@ -584,41 +892,44 @@
                 {
                     "name": "Sebastian Bergmann",
                     "email": "sebastian@phpunit.de"
+                },
+                {
+                    "name": "SpacePossum"
                 }
             ],
-            "description": "Diff implementation",
-            "homepage": "https://github.com/sebastianbergmann/diff",
+            "description": "sebastian/diff v2 backport support for PHP5.6",
+            "homepage": "https://github.com/PHP-CS-Fixer",
             "keywords": [
                 "diff"
             ],
-            "time": "2017-05-22 07:24:03"
+            "time": "2017-10-19T09:58:18+00:00"
         },
         {
             "name": "symfony/event-dispatcher",
-            "version": "v3.3.0",
+            "version": "v4.0.3",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/event-dispatcher.git",
-                "reference": "a9f8b02b0ef07302eca92cd4bba73200b7980e9c"
+                "reference": "74d33aac36208c4d6757807d9f598f0133a3a4eb"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/event-dispatcher/zipball/a9f8b02b0ef07302eca92cd4bba73200b7980e9c",
-                "reference": "a9f8b02b0ef07302eca92cd4bba73200b7980e9c",
+                "url": "https://api.github.com/repos/symfony/event-dispatcher/zipball/74d33aac36208c4d6757807d9f598f0133a3a4eb",
+                "reference": "74d33aac36208c4d6757807d9f598f0133a3a4eb",
                 "shasum": ""
             },
             "require": {
-                "php": ">=5.5.9"
+                "php": "^7.1.3"
             },
             "conflict": {
-                "symfony/dependency-injection": "<3.3"
+                "symfony/dependency-injection": "<3.4"
             },
             "require-dev": {
                 "psr/log": "~1.0",
-                "symfony/config": "~2.8|~3.0",
-                "symfony/dependency-injection": "~3.3",
-                "symfony/expression-language": "~2.8|~3.0",
-                "symfony/stopwatch": "~2.8|~3.0"
+                "symfony/config": "~3.4|~4.0",
+                "symfony/dependency-injection": "~3.4|~4.0",
+                "symfony/expression-language": "~3.4|~4.0",
+                "symfony/stopwatch": "~3.4|~4.0"
             },
             "suggest": {
                 "symfony/dependency-injection": "",
@@ -627,7 +938,7 @@
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "3.3-dev"
+                    "dev-master": "4.0-dev"
                 }
             },
             "autoload": {
@@ -654,29 +965,29 @@
             ],
             "description": "Symfony EventDispatcher Component",
             "homepage": "https://symfony.com",
-            "time": "2017-05-04 12:23:07"
+            "time": "2018-01-03T07:38:00+00:00"
         },
         {
             "name": "symfony/filesystem",
-            "version": "v3.3.0",
+            "version": "v4.0.3",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/filesystem.git",
-                "reference": "c709670bf64721202ddbe4162846f250735842c0"
+                "reference": "760e47a4ee64b4c48f4b30017011e09d4c0f05ed"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/filesystem/zipball/c709670bf64721202ddbe4162846f250735842c0",
-                "reference": "c709670bf64721202ddbe4162846f250735842c0",
+                "url": "https://api.github.com/repos/symfony/filesystem/zipball/760e47a4ee64b4c48f4b30017011e09d4c0f05ed",
+                "reference": "760e47a4ee64b4c48f4b30017011e09d4c0f05ed",
                 "shasum": ""
             },
             "require": {
-                "php": ">=5.5.9"
+                "php": "^7.1.3"
             },
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "3.3-dev"
+                    "dev-master": "4.0-dev"
                 }
             },
             "autoload": {
@@ -703,29 +1014,29 @@
             ],
             "description": "Symfony Filesystem Component",
             "homepage": "https://symfony.com",
-            "time": "2017-05-28 14:08:56"
+            "time": "2018-01-03T07:38:00+00:00"
         },
         {
             "name": "symfony/finder",
-            "version": "v3.3.0",
+            "version": "v4.0.3",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/finder.git",
-                "reference": "30cb2a2c09627823a7243638dd456de4e2748fed"
+                "reference": "8b08180f2b7ccb41062366b9ad91fbc4f1af8601"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/finder/zipball/30cb2a2c09627823a7243638dd456de4e2748fed",
-                "reference": "30cb2a2c09627823a7243638dd456de4e2748fed",
+                "url": "https://api.github.com/repos/symfony/finder/zipball/8b08180f2b7ccb41062366b9ad91fbc4f1af8601",
+                "reference": "8b08180f2b7ccb41062366b9ad91fbc4f1af8601",
                 "shasum": ""
             },
             "require": {
-                "php": ">=5.5.9"
+                "php": "^7.1.3"
             },
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "3.3-dev"
+                    "dev-master": "4.0-dev"
                 }
             },
             "autoload": {
@@ -752,29 +1063,197 @@
             ],
             "description": "Symfony Finder Component",
             "homepage": "https://symfony.com",
-            "time": "2017-05-25 23:10:31"
+            "time": "2018-01-03T07:38:00+00:00"
         },
         {
-            "name": "symfony/process",
-            "version": "v3.3.0",
+            "name": "symfony/options-resolver",
+            "version": "v4.0.3",
             "source": {
                 "type": "git",
-                "url": "https://github.com/symfony/process.git",
-                "reference": "8e30690c67aafb6c7992d6d8eb0d707807dd3eaf"
+                "url": "https://github.com/symfony/options-resolver.git",
+                "reference": "30d9240b30696a69e893534c9fc4a5c72ab6689b"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/process/zipball/8e30690c67aafb6c7992d6d8eb0d707807dd3eaf",
-                "reference": "8e30690c67aafb6c7992d6d8eb0d707807dd3eaf",
+                "url": "https://api.github.com/repos/symfony/options-resolver/zipball/30d9240b30696a69e893534c9fc4a5c72ab6689b",
+                "reference": "30d9240b30696a69e893534c9fc4a5c72ab6689b",
                 "shasum": ""
             },
             "require": {
-                "php": ">=5.5.9"
+                "php": "^7.1.3"
             },
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "3.3-dev"
+                    "dev-master": "4.0-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Symfony\\Component\\OptionsResolver\\": ""
+                },
+                "exclude-from-classmap": [
+                    "/Tests/"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Fabien Potencier",
+                    "email": "fabien@symfony.com"
+                },
+                {
+                    "name": "Symfony Community",
+                    "homepage": "https://symfony.com/contributors"
+                }
+            ],
+            "description": "Symfony OptionsResolver Component",
+            "homepage": "https://symfony.com",
+            "keywords": [
+                "config",
+                "configuration",
+                "options"
+            ],
+            "time": "2018-01-03T07:38:00+00:00"
+        },
+        {
+            "name": "symfony/polyfill-php70",
+            "version": "v1.6.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/symfony/polyfill-php70.git",
+                "reference": "0442b9c0596610bd24ae7b5f0a6cdbbc16d9fcff"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/symfony/polyfill-php70/zipball/0442b9c0596610bd24ae7b5f0a6cdbbc16d9fcff",
+                "reference": "0442b9c0596610bd24ae7b5f0a6cdbbc16d9fcff",
+                "shasum": ""
+            },
+            "require": {
+                "paragonie/random_compat": "~1.0|~2.0",
+                "php": ">=5.3.3"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "1.6-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Symfony\\Polyfill\\Php70\\": ""
+                },
+                "files": [
+                    "bootstrap.php"
+                ],
+                "classmap": [
+                    "Resources/stubs"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Nicolas Grekas",
+                    "email": "p@tchwork.com"
+                },
+                {
+                    "name": "Symfony Community",
+                    "homepage": "https://symfony.com/contributors"
+                }
+            ],
+            "description": "Symfony polyfill backporting some PHP 7.0+ features to lower PHP versions",
+            "homepage": "https://symfony.com",
+            "keywords": [
+                "compatibility",
+                "polyfill",
+                "portable",
+                "shim"
+            ],
+            "time": "2017-10-11T12:05:26+00:00"
+        },
+        {
+            "name": "symfony/polyfill-php72",
+            "version": "v1.6.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/symfony/polyfill-php72.git",
+                "reference": "6de4f4884b97abbbed9f0a84a95ff2ff77254254"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/symfony/polyfill-php72/zipball/6de4f4884b97abbbed9f0a84a95ff2ff77254254",
+                "reference": "6de4f4884b97abbbed9f0a84a95ff2ff77254254",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.3.3"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "1.6-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Symfony\\Polyfill\\Php72\\": ""
+                },
+                "files": [
+                    "bootstrap.php"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Nicolas Grekas",
+                    "email": "p@tchwork.com"
+                },
+                {
+                    "name": "Symfony Community",
+                    "homepage": "https://symfony.com/contributors"
+                }
+            ],
+            "description": "Symfony polyfill backporting some PHP 7.2+ features to lower PHP versions",
+            "homepage": "https://symfony.com",
+            "keywords": [
+                "compatibility",
+                "polyfill",
+                "portable",
+                "shim"
+            ],
+            "time": "2017-10-11T12:05:26+00:00"
+        },
+        {
+            "name": "symfony/process",
+            "version": "v4.0.3",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/symfony/process.git",
+                "reference": "2145b3e8137e463b1051b79440a59b38220944f0"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/symfony/process/zipball/2145b3e8137e463b1051b79440a59b38220944f0",
+                "reference": "2145b3e8137e463b1051b79440a59b38220944f0",
+                "shasum": ""
+            },
+            "require": {
+                "php": "^7.1.3"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "4.0-dev"
                 }
             },
             "autoload": {
@@ -801,29 +1280,29 @@
             ],
             "description": "Symfony Process Component",
             "homepage": "https://symfony.com",
-            "time": "2017-05-22 12:32:03"
+            "time": "2018-01-03T07:38:00+00:00"
         },
         {
             "name": "symfony/stopwatch",
-            "version": "v3.3.0",
+            "version": "v4.0.3",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/stopwatch.git",
-                "reference": "602a15299dc01556013b07167d4f5d3a60e90d15"
+                "reference": "d52321f0e2b596bd03b5d1dd6eebe71caa925704"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/stopwatch/zipball/602a15299dc01556013b07167d4f5d3a60e90d15",
-                "reference": "602a15299dc01556013b07167d4f5d3a60e90d15",
+                "url": "https://api.github.com/repos/symfony/stopwatch/zipball/d52321f0e2b596bd03b5d1dd6eebe71caa925704",
+                "reference": "d52321f0e2b596bd03b5d1dd6eebe71caa925704",
                 "shasum": ""
             },
             "require": {
-                "php": ">=5.5.9"
+                "php": "^7.1.3"
             },
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "3.3-dev"
+                    "dev-master": "4.0-dev"
                 }
             },
             "autoload": {
@@ -850,16 +1329,16 @@
             ],
             "description": "Symfony Stopwatch Component",
             "homepage": "https://symfony.com",
-            "time": "2017-04-12 14:14:56"
+            "time": "2018-01-03T07:38:00+00:00"
         }
     ],
     "aliases": [],
     "minimum-stability": "stable",
-    "stability-flags": {
-        "symfony/yaml": 20
-    },
+    "stability-flags": [],
     "prefer-stable": false,
     "prefer-lowest": false,
-    "platform": [],
+    "platform": {
+        "php": "^7"
+    },
     "platform-dev": []
 }
diff --git a/src/application.php b/src/application.php
index db3dbb2..2f19fc4 100644
--- a/src/application.php
+++ b/src/application.php
@@ -26,7 +26,7 @@ $application->register('render')
     ->setCode(function (Console\Input\InputInterface $input, Console\Output\OutputInterface $output) {
         $backgroundColor = $input->getOption('background');
 
-        if (preg_match('/^#[a-fA-F0-9]{6}|transparent$/', $backgroundColor) === 0) {
+        if (0 === preg_match('/^#[a-fA-F0-9]{6}|transparent$/', $backgroundColor)) {
             throw new Console\Exception\InvalidArgumentException(sprintf('Invalid background color "%s". It must be a valid hex color or "transparent".', $backgroundColor));
         }
 
@@ -36,19 +36,19 @@ $application->register('render')
         $overrideFile = dirname($inputFile).DIRECTORY_SEPARATOR.basename($inputFile, '.'.$inputFileExtension).'.'.$input->getOption('override').'.'.$inputFileExtension;
 
         $outputFormat = $input->getOption('output-format');
-        $outputFile = $input->getOption('output-file') ?: getcwd().DIRECTORY_SEPARATOR.'docker-compose.'.($outputFormat === 'dot' ? $outputFormat : 'png');
+        $outputFile = $input->getOption('output-file') ?: getcwd().DIRECTORY_SEPARATOR.'docker-compose.'.('dot' === $outputFormat ? $outputFormat : 'png');
         $onlyServices = $input->getOption('only');
 
-        if (in_array($outputFormat, ['dot', 'image', 'display']) === false) {
+        if (false === in_array($outputFormat, ['dot', 'image', 'display'])) {
             throw new Console\Exception\InvalidArgumentException(sprintf('Invalid output format "%s". It must be one of "dot", "image" or "display".', $outputFormat));
         }
 
-        if ($outputFormat === 'display') {
+        if ('display' === $outputFormat) {
             if ($input->getOption('force') || $input->getOption('output-file')) {
                 $output->writeln('<comment>The following options are ignored with the "display" output format: "--force", "--output-file"</comment>');
             }
         } else {
-            if (file_exists($outputFile) === true && $input->getOption('force') === false) {
+            if (true === file_exists($outputFile) && false === $input->getOption('force')) {
                 throw new Console\Exception\InvalidArgumentException(sprintf('File "%s" already exists. Use the "--force" option to overwrite it.', $outputFile));
             }
         }
@@ -103,19 +103,19 @@ $application->register('render')
         }
 
         $flags = 0;
-        if ($input->getOption('no-volumes') === true) {
+        if (true === $input->getOption('no-volumes')) {
             $logger('<comment>Volumes</comment> will not be displayed');
 
             $flags |= WITHOUT_VOLUMES;
         }
 
-        if ($input->getOption('no-networks') === true) {
+        if (true === $input->getOption('no-networks')) {
             $logger('<comment>Networks</comment> will not be displayed');
 
             $flags |= WITHOUT_NETWORKS;
         }
 
-        if ($input->getOption('no-ports') === true) {
+        if (true === $input->getOption('no-ports')) {
             $logger('<comment>Ports</comment> will not be displayed');
 
             $flags |= WITHOUT_PORTS;
diff --git a/src/functions.php b/src/functions.php
index 6ca659f..7f6c481 100644
--- a/src/functions.php
+++ b/src/functions.php
@@ -20,7 +20,7 @@ const WITHOUT_PORTS = 4;
  *
  * @return callable
  */
-function logger(OutputInterface $output) : callable
+function logger(OutputInterface $output): callable
 {
     return function (string $message, int $verbosity = null) use ($output) {
         $output->writeln(sprintf('[%s] %s', date(DATE_ISO8601), $message), $verbosity ?: OutputInterface::VERBOSITY_VERBOSE);
@@ -34,9 +34,9 @@ function logger(OutputInterface $output) : callable
  *
  * @return array
  */
-function readConfiguration(string $path) : array
+function readConfiguration(string $path): array
 {
-    if (file_exists($path) === false) {
+    if (false === file_exists($path)) {
         throw new \InvalidArgumentException(sprintf('File "%s" does not exist', $path));
     }
 
@@ -54,9 +54,9 @@ function readConfiguration(string $path) : array
  *
  * @return array List of service definitions exctracted from the configuration
  */
-function fetchServices(array $configuration) : array
+function fetchServices(array $configuration): array
 {
-    if (isset($configuration['version']) === false || (int) $configuration['version'] === 1) {
+    if (false === isset($configuration['version']) || 1 === (int) $configuration['version']) {
         return $configuration;
     }
 
@@ -70,9 +70,9 @@ function fetchServices(array $configuration) : array
  *
  * @return array List of service definitions exctracted from the configuration
  */
-function fetchVolumes(array $configuration) : array
+function fetchVolumes(array $configuration): array
 {
-    if (isset($configuration['version']) === false || (int) $configuration['version'] === 1) {
+    if (false === isset($configuration['version']) || 1 === (int) $configuration['version']) {
         return [];
     }
 
@@ -86,9 +86,9 @@ function fetchVolumes(array $configuration) : array
  *
  * @return array List of service definitions exctracted from the configuration
  */
-function fetchNetworks(array $configuration) : array
+function fetchNetworks(array $configuration): array
 {
-    if (isset($configuration['version']) === false || (int) $configuration['version'] === 1) {
+    if (false === isset($configuration['version']) || 1 === (int) $configuration['version']) {
         return [];
     }
 
@@ -106,7 +106,7 @@ function fetchNetworks(array $configuration) : array
  *
  * @return Graph The complete graph for the given list of services
  */
-function createGraph(array $services, array $volumes, array $networks, string $path, int $flags) : Graph
+function createGraph(array $services, array $volumes, array $networks, string $path, int $flags): Graph
 {
     return makeVerticesAndEdges(new Graph(), $services, $volumes, $networks, $path, $flags);
 }
@@ -120,14 +120,14 @@ function createGraph(array $services, array $volumes, array $networks, string $p
  *
  * @return Graph A copy of the input graph with style attributes
  */
-function applyGraphvizStyle(Graph $graph, bool $horizontal, string $background) : Graph
+function applyGraphvizStyle(Graph $graph, bool $horizontal, string $background): Graph
 {
     $graph = $graph->createGraphClone();
     $graph->setAttribute('graphviz.graph.bgcolor', $background);
     $graph->setAttribute('graphviz.graph.pad', '0.5');
     $graph->setAttribute('graphviz.graph.ratio', 'fill');
 
-    if ($horizontal === true) {
+    if (true === $horizontal) {
         $graph->setAttribute('graphviz.graph.rankdir', 'LR');
     }
 
@@ -158,7 +158,7 @@ function applyGraphvizStyle(Graph $graph, bool $horizontal, string $background)
             case 'port':
                 $vertex->setAttribute('graphviz.shape', 'circle');
 
-                if (($proto = $vertex->getAttribute('docker_compose.proto')) === 'udp') {
+                if ('udp' === ($proto = $vertex->getAttribute('docker_compose.proto'))) {
                     $vertex->setAttribute('graphviz.style', 'dashed');
                 }
                 break;
@@ -193,10 +193,10 @@ function applyGraphvizStyle(Graph $graph, bool $horizontal, string $background)
                 break;
         }
 
-        if (($alias = $edge->getAttribute('docker_compose.alias')) !== null) {
+        if (null !== ($alias = $edge->getAttribute('docker_compose.alias'))) {
             $edge->setAttribute('graphviz.label', $alias);
 
-            if ($edge->getAttribute('docker_compose.condition') !== null) {
+            if (null !== $edge->getAttribute('docker_compose.condition')) {
                 $edge->setAttribute('graphviz.fontsize', '10');
             }
         }
@@ -220,19 +220,19 @@ function applyGraphvizStyle(Graph $graph, bool $horizontal, string $background)
  *
  * @return Graph A copy of the input graph with vertices and edges for services
  */
-function makeVerticesAndEdges(Graph $graph, array $services, array $volumes, array $networks, string $path, int $flags) : Graph
+function makeVerticesAndEdges(Graph $graph, array $services, array $volumes, array $networks, string $path, int $flags): Graph
 {
-    if (((bool) ($flags & WITHOUT_VOLUMES)) === false) {
+    if (false === ((bool) ($flags & WITHOUT_VOLUMES))) {
         foreach (array_keys($volumes) as $volume) {
             addVolume($graph, 'named: '.$volume);
         }
     }
 
-    if (((bool) ($flags & WITHOUT_NETWORKS)) === false) {
+    if (false === ((bool) ($flags & WITHOUT_NETWORKS))) {
         foreach ($networks as $network => $definition) {
             addNetwork(
                 $graph, 'net: '.$network,
-                isset($definition['external']) && $definition['external'] === true ? 'external_network' : 'network'
+                isset($definition['external']) && true === $definition['external'] ? 'external_network' : 'network'
             );
         }
     }
@@ -302,7 +302,7 @@ function makeVerticesAndEdges(Graph $graph, array $services, array $volumes, arr
             );
         }
 
-        if (((bool) ($flags & WITHOUT_VOLUMES)) === false) {
+        if (false === ((bool) ($flags & WITHOUT_VOLUMES))) {
             $serviceVolumes = [];
 
             foreach ($definition['volumes'] ?? [] as $volume) {
@@ -314,7 +314,7 @@ function makeVerticesAndEdges(Graph $graph, array $services, array $volumes, arr
             foreach ($serviceVolumes as $container => $volume) {
                 list($host, $attr) = $volume;
 
-                if ($host[0] !== '.' && $host[0] !== DIRECTORY_SEPARATOR) {
+                if ('.' !== $host[0] && DIRECTORY_SEPARATOR !== $host[0]) {
                     $host = 'named: '.$host;
                 }
 
@@ -323,12 +323,12 @@ function makeVerticesAndEdges(Graph $graph, array $services, array $volumes, arr
                     $graph->getVertex($service),
                     'volumes',
                     $host !== $container ? $container : null,
-                    $attr !== 'ro'
+                    'ro' !== $attr
                 );
             }
         }
 
-        if (((bool) ($flags & WITHOUT_PORTS)) === false) {
+        if (false === ((bool) ($flags & WITHOUT_PORTS))) {
             foreach ($definition['ports'] ?? [] as $port) {
                 list($host, $container, $proto) = explodeMapping($port);
 
@@ -341,7 +341,7 @@ function makeVerticesAndEdges(Graph $graph, array $services, array $volumes, arr
             }
         }
 
-        if (((bool) ($flags & WITHOUT_NETWORKS)) === false) {
+        if (false === ((bool) ($flags & WITHOUT_NETWORKS))) {
             foreach ($definition['networks'] ?? [] as $network => $config) {
                 $network = is_int($network) ? $config : $network;
                 $config = is_int($network) ? [] : $config;
@@ -371,7 +371,7 @@ function makeVerticesAndEdges(Graph $graph, array $services, array $volumes, arr
  */
 function addService(Graph $graph, string $service, string $type = null)
 {
-    if ($graph->hasVertex($service) === true) {
+    if (true === $graph->hasVertex($service)) {
         return $graph->getVertex($service);
     }
 
@@ -392,7 +392,7 @@ function addService(Graph $graph, string $service, string $type = null)
  */
 function addPort(Graph $graph, int $port, string $proto = null)
 {
-    if ($graph->hasVertex($port) === true) {
+    if (true === $graph->hasVertex($port)) {
         return $graph->getVertex($port);
     }
 
@@ -413,7 +413,7 @@ function addPort(Graph $graph, int $port, string $proto = null)
  */
 function addVolume(Graph $graph, string $path)
 {
-    if ($graph->hasVertex($path) === true) {
+    if (true === $graph->hasVertex($path)) {
         return $graph->getVertex($path);
     }
 
@@ -434,7 +434,7 @@ function addVolume(Graph $graph, string $path)
  */
 function addNetwork(Graph $graph, string $name, string $type = null)
 {
-    if ($graph->hasVertex($name) === true) {
+    if (true === $graph->hasVertex($name)) {
         return $graph->getVertex($name);
     }
 
@@ -456,7 +456,7 @@ function addNetwork(Graph $graph, string $name, string $type = null)
  *
  * @return Edge\Directed
  */
-function addRelation(Vertex $from, Vertex $to, string $type, string $alias = null, bool $bidirectional = false, bool $condition = false) : Edge\Directed
+function addRelation(Vertex $from, Vertex $to, string $type, string $alias = null, bool $bidirectional = false, bool $condition = false): Edge\Directed
 {
     $edge = null;
 
@@ -476,7 +476,7 @@ function addRelation(Vertex $from, Vertex $to, string $type, string $alias = nul
 
     $edge->setAttribute('docker_compose.type', $type);
 
-    if ($alias !== null) {
+    if (null !== $alias) {
         $edge->setAttribute('docker_compose.alias', $alias);
     }
 
@@ -497,7 +497,7 @@ function addRelation(Vertex $from, Vertex $to, string $type, string $alias = nul
  * @return array An 2 items array containing the parts of the mapping.
  *               If the mapping does not specify a second part, the first one will be repeated
  */
-function explodeMapping($mapping) : array
+function explodeMapping($mapping): array
 {
     $parts = explode(':', $mapping);
     $parts[1] = $parts[1] ?? $parts[0];