diff --git a/composer.json b/composer.json
index 6350c9f..ba635a1 100644
--- a/composer.json
+++ b/composer.json
@@ -20,8 +20,11 @@
 		"phpstan/phpstan": "^0.12.42"
 	},
 	"require-dev": {
+		"php-parallel-lint/php-parallel-lint": "^1.2",
+		"php-parallel-lint/php-console-highlighter": "^0.5.0",
 		"phpunit/php-timer": "1.0.*",
-		"phpunit/phpunit": "4.7.*"
+		"phpunit/phpunit": "4.7.*",
+		"spaze/coding-standard": "^0.0.3"
 	},
 	"autoload": {
 		"psr-4": {
@@ -30,9 +33,13 @@
 	},
 	"minimum-stability": "stable",
 	"scripts": {
+		"lint": "vendor/bin/parallel-lint --colors src/ tests/",
+		"phpcs": "vendor/bin/phpcs src/ tests/",
 		"phpstan-dev": "vendor/bin/phpstan --ansi analyse --configuration phpstan.neon",
 		"phpunit-dev": "php vendor/phpunit/phpunit/phpunit --colors=always --verbose",
 		"test": [
+			"@lint",
+			"@phpcs",
 			"@phpstan-dev",
 			"@phpunit-dev"
 		]
diff --git a/composer.lock b/composer.lock
index 0d26b36..328074c 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": "20de5e92c1270285d7de54c472a0cc00",
+    "content-hash": "c29931c95ebf65dc08a87f6aa8c640c4",
     "packages": [
         {
             "name": "phpstan/phpstan",
@@ -64,6 +64,72 @@
         }
     ],
     "packages-dev": [
+        {
+            "name": "dealerdirect/phpcodesniffer-composer-installer",
+            "version": "v0.7.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/Dealerdirect/phpcodesniffer-composer-installer.git",
+                "reference": "e8d808670b8f882188368faaf1144448c169c0b7"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/Dealerdirect/phpcodesniffer-composer-installer/zipball/e8d808670b8f882188368faaf1144448c169c0b7",
+                "reference": "e8d808670b8f882188368faaf1144448c169c0b7",
+                "shasum": ""
+            },
+            "require": {
+                "composer-plugin-api": "^1.0 || ^2.0",
+                "php": ">=5.3",
+                "squizlabs/php_codesniffer": "^2 || ^3 || 4.0.x-dev"
+            },
+            "require-dev": {
+                "composer/composer": "*",
+                "phpcompatibility/php-compatibility": "^9.0",
+                "sensiolabs/security-checker": "^4.1.0"
+            },
+            "type": "composer-plugin",
+            "extra": {
+                "class": "Dealerdirect\\Composer\\Plugin\\Installers\\PHPCodeSniffer\\Plugin"
+            },
+            "autoload": {
+                "psr-4": {
+                    "Dealerdirect\\Composer\\Plugin\\Installers\\PHPCodeSniffer\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Franck Nijhof",
+                    "email": "franck.nijhof@dealerdirect.com",
+                    "homepage": "http://www.frenck.nl",
+                    "role": "Developer / IT Manager"
+                }
+            ],
+            "description": "PHP_CodeSniffer Standards Composer Installer Plugin",
+            "homepage": "http://www.dealerdirect.com",
+            "keywords": [
+                "PHPCodeSniffer",
+                "PHP_CodeSniffer",
+                "code quality",
+                "codesniffer",
+                "composer",
+                "installer",
+                "phpcs",
+                "plugin",
+                "qa",
+                "quality",
+                "standard",
+                "standards",
+                "style guide",
+                "stylecheck",
+                "tests"
+            ],
+            "time": "2020-06-25T14:57:39+00:00"
+        },
         {
             "name": "doctrine/instantiator",
             "version": "1.3.0",
@@ -120,6 +186,153 @@
             ],
             "time": "2019-10-21T16:45:58+00:00"
         },
+        {
+            "name": "php-parallel-lint/php-console-color",
+            "version": "v0.3",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/php-parallel-lint/PHP-Console-Color.git",
+                "reference": "b6af326b2088f1ad3b264696c9fd590ec395b49e"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/php-parallel-lint/PHP-Console-Color/zipball/b6af326b2088f1ad3b264696c9fd590ec395b49e",
+                "reference": "b6af326b2088f1ad3b264696c9fd590ec395b49e",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.4.0"
+            },
+            "replace": {
+                "jakub-onderka/php-console-color": "*"
+            },
+            "require-dev": {
+                "php-parallel-lint/php-code-style": "1.0",
+                "php-parallel-lint/php-parallel-lint": "1.0",
+                "php-parallel-lint/php-var-dump-check": "0.*",
+                "phpunit/phpunit": "~4.3",
+                "squizlabs/php_codesniffer": "1.*"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "JakubOnderka\\PhpConsoleColor\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "BSD-2-Clause"
+            ],
+            "authors": [
+                {
+                    "name": "Jakub Onderka",
+                    "email": "jakub.onderka@gmail.com"
+                }
+            ],
+            "time": "2020-05-14T05:47:14+00:00"
+        },
+        {
+            "name": "php-parallel-lint/php-console-highlighter",
+            "version": "v0.5",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/php-parallel-lint/PHP-Console-Highlighter.git",
+                "reference": "21bf002f077b177f056d8cb455c5ed573adfdbb8"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/php-parallel-lint/PHP-Console-Highlighter/zipball/21bf002f077b177f056d8cb455c5ed573adfdbb8",
+                "reference": "21bf002f077b177f056d8cb455c5ed573adfdbb8",
+                "shasum": ""
+            },
+            "require": {
+                "ext-tokenizer": "*",
+                "php": ">=5.4.0",
+                "php-parallel-lint/php-console-color": "~0.2"
+            },
+            "replace": {
+                "jakub-onderka/php-console-highlighter": "*"
+            },
+            "require-dev": {
+                "php-parallel-lint/php-code-style": "~1.0",
+                "php-parallel-lint/php-parallel-lint": "~1.0",
+                "php-parallel-lint/php-var-dump-check": "~0.1",
+                "phpunit/phpunit": "~4.0",
+                "squizlabs/php_codesniffer": "~1.5"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "JakubOnderka\\PhpConsoleHighlighter\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Jakub Onderka",
+                    "email": "acci@acci.cz",
+                    "homepage": "http://www.acci.cz/"
+                }
+            ],
+            "description": "Highlight PHP code in terminal",
+            "time": "2020-05-13T07:37:49+00:00"
+        },
+        {
+            "name": "php-parallel-lint/php-parallel-lint",
+            "version": "v1.2.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/php-parallel-lint/PHP-Parallel-Lint.git",
+                "reference": "474f18bc6cc6aca61ca40bfab55139de614e51ca"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/php-parallel-lint/PHP-Parallel-Lint/zipball/474f18bc6cc6aca61ca40bfab55139de614e51ca",
+                "reference": "474f18bc6cc6aca61ca40bfab55139de614e51ca",
+                "shasum": ""
+            },
+            "require": {
+                "ext-json": "*",
+                "php": ">=5.4.0"
+            },
+            "replace": {
+                "grogy/php-parallel-lint": "*",
+                "jakub-onderka/php-parallel-lint": "*"
+            },
+            "require-dev": {
+                "nette/tester": "^1.3 || ^2.0",
+                "php-parallel-lint/php-console-highlighter": "~0.3",
+                "squizlabs/php_codesniffer": "~3.0"
+            },
+            "suggest": {
+                "php-parallel-lint/php-console-highlighter": "Highlight syntax in code snippet"
+            },
+            "bin": [
+                "parallel-lint"
+            ],
+            "type": "library",
+            "autoload": {
+                "classmap": [
+                    "./"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "BSD-2-Clause"
+            ],
+            "authors": [
+                {
+                    "name": "Jakub Onderka",
+                    "email": "ahoj@jakubonderka.cz"
+                }
+            ],
+            "description": "This tool check syntax of PHP files about 20x faster than serial check.",
+            "homepage": "https://github.com/php-parallel-lint/PHP-Parallel-Lint",
+            "time": "2020-04-04T12:18:32+00:00"
+        },
         {
             "name": "phpdocumentor/reflection-common",
             "version": "2.1.0",
@@ -331,6 +544,55 @@
             ],
             "time": "2020-03-05T15:02:03+00:00"
         },
+        {
+            "name": "phpstan/phpdoc-parser",
+            "version": "0.4.9",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/phpstan/phpdoc-parser.git",
+                "reference": "98a088b17966bdf6ee25c8a4b634df313d8aa531"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/phpstan/phpdoc-parser/zipball/98a088b17966bdf6ee25c8a4b634df313d8aa531",
+                "reference": "98a088b17966bdf6ee25c8a4b634df313d8aa531",
+                "shasum": ""
+            },
+            "require": {
+                "php": "^7.1 || ^8.0"
+            },
+            "require-dev": {
+                "consistence/coding-standard": "^3.5",
+                "ergebnis/composer-normalize": "^2.0.2",
+                "jakub-onderka/php-parallel-lint": "^0.9.2",
+                "phing/phing": "^2.16.0",
+                "phpstan/extension-installer": "^1.0",
+                "phpstan/phpstan": "^0.12.26",
+                "phpstan/phpstan-strict-rules": "^0.12",
+                "phpunit/phpunit": "^6.3",
+                "slevomat/coding-standard": "^4.7.2",
+                "symfony/process": "^4.0"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "0.4-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "PHPStan\\PhpDocParser\\": [
+                        "src/"
+                    ]
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "description": "PHPDoc parser with support for nullable, intersection and generic types",
+            "time": "2020-08-03T20:32:43+00:00"
+        },
         {
             "name": "phpunit/php-code-coverage",
             "version": "2.2.4",
@@ -1081,6 +1343,153 @@
             "homepage": "https://github.com/sebastianbergmann/version",
             "time": "2015-06-21T13:59:46+00:00"
         },
+        {
+            "name": "slevomat/coding-standard",
+            "version": "6.4.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/slevomat/coding-standard.git",
+                "reference": "bf3a16a630d8245c350b459832a71afa55c02fd3"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/slevomat/coding-standard/zipball/bf3a16a630d8245c350b459832a71afa55c02fd3",
+                "reference": "bf3a16a630d8245c350b459832a71afa55c02fd3",
+                "shasum": ""
+            },
+            "require": {
+                "dealerdirect/phpcodesniffer-composer-installer": "^0.6.2 || ^0.7",
+                "php": "^7.1 || ^8.0",
+                "phpstan/phpdoc-parser": "0.4.5 - 0.4.9",
+                "squizlabs/php_codesniffer": "^3.5.6"
+            },
+            "require-dev": {
+                "phing/phing": "2.16.3",
+                "php-parallel-lint/php-parallel-lint": "1.2.0",
+                "phpstan/phpstan": "0.12.40",
+                "phpstan/phpstan-deprecation-rules": "0.12.5",
+                "phpstan/phpstan-phpunit": "0.12.16",
+                "phpstan/phpstan-strict-rules": "0.12.5",
+                "phpunit/phpunit": "7.5.20|8.5.5|9.3.8"
+            },
+            "type": "phpcodesniffer-standard",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "6.x-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "SlevomatCodingStandard\\": "SlevomatCodingStandard"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "description": "Slevomat Coding Standard for PHP_CodeSniffer complements Consistence Coding Standard by providing sniffs with additional checks.",
+            "funding": [
+                {
+                    "url": "https://github.com/kukulich",
+                    "type": "github"
+                },
+                {
+                    "url": "https://tidelift.com/funding/github/packagist/slevomat/coding-standard",
+                    "type": "tidelift"
+                }
+            ],
+            "time": "2020-08-31T07:02:52+00:00"
+        },
+        {
+            "name": "spaze/coding-standard",
+            "version": "v0.0.3",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/spaze/coding-standard.git",
+                "reference": "b5e36d7a8dbe2519813e20e7b1ffee6d537ecded"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/spaze/coding-standard/zipball/b5e36d7a8dbe2519813e20e7b1ffee6d537ecded",
+                "reference": "b5e36d7a8dbe2519813e20e7b1ffee6d537ecded",
+                "shasum": ""
+            },
+            "require": {
+                "php": "^7.1",
+                "slevomat/coding-standard": "^6.4.0",
+                "squizlabs/php_codesniffer": "^3.5.6"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "Spaze\\CodingStandard\\": "src"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Michal Špaček",
+                    "email": "mail@michalspacek.cz",
+                    "homepage": "https://www.michalspacek.com"
+                }
+            ],
+            "description": "Coding Standard – PHP Code Sniffer Rules",
+            "time": "2020-09-13T15:33:46+00:00"
+        },
+        {
+            "name": "squizlabs/php_codesniffer",
+            "version": "3.5.6",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/squizlabs/PHP_CodeSniffer.git",
+                "reference": "e97627871a7eab2f70e59166072a6b767d5834e0"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/squizlabs/PHP_CodeSniffer/zipball/e97627871a7eab2f70e59166072a6b767d5834e0",
+                "reference": "e97627871a7eab2f70e59166072a6b767d5834e0",
+                "shasum": ""
+            },
+            "require": {
+                "ext-simplexml": "*",
+                "ext-tokenizer": "*",
+                "ext-xmlwriter": "*",
+                "php": ">=5.4.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "^4.0 || ^5.0 || ^6.0 || ^7.0"
+            },
+            "bin": [
+                "bin/phpcs",
+                "bin/phpcbf"
+            ],
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "3.x-dev"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "BSD-3-Clause"
+            ],
+            "authors": [
+                {
+                    "name": "Greg Sherwood",
+                    "role": "lead"
+                }
+            ],
+            "description": "PHP_CodeSniffer tokenizes PHP, JavaScript and CSS files and detects violations of a defined set of coding standards.",
+            "homepage": "https://github.com/squizlabs/PHP_CodeSniffer",
+            "keywords": [
+                "phpcs",
+                "standards"
+            ],
+            "time": "2020-08-10T04:50:15+00:00"
+        },
         {
             "name": "symfony/polyfill-ctype",
             "version": "v1.17.0",
diff --git a/phpcs.xml b/phpcs.xml
new file mode 100644
index 0000000..be3c3b1
--- /dev/null
+++ b/phpcs.xml
@@ -0,0 +1,9 @@
+<?xml version="1.0"?>
+<ruleset name="VatCalculator">
+	<arg name="extensions" value="php"/>
+	<arg name="cache"/>
+	<arg name="colors"/>
+	<arg value="s"/>
+	<arg value="p"/>
+	<rule ref="vendor/spaze/coding-standard/src/ruleset.xml"/>
+</ruleset>
diff --git a/src/VatCalculator.php b/src/VatCalculator.php
index c511c6b..746d8fb 100644
--- a/src/VatCalculator.php
+++ b/src/VatCalculator.php
@@ -17,7 +17,7 @@ class VatCalculator
 	 *
 	 * @var string
 	 */
-	const VAT_SERVICE_URL = 'https://ec.europa.eu/taxation_customs/vies/checkVatService.wsdl';
+	public const VAT_SERVICE_URL = 'https://ec.europa.eu/taxation_customs/vies/checkVatService.wsdl';
 
 	/** @var SoapClient */
 	private $soapClient;
diff --git a/src/VatPrice.php b/src/VatPrice.php
index 319a345..92558ab 100644
--- a/src/VatPrice.php
+++ b/src/VatPrice.php
@@ -1,10 +1,8 @@
 <?php
 declare(strict_types = 1);
 
-
 namespace Spaze\VatCalculator;
 
-
 class VatPrice
 {
 
diff --git a/src/VatRates.php b/src/VatRates.php
index bacf0ed..d45311f 100644
--- a/src/VatRates.php
+++ b/src/VatRates.php
@@ -358,7 +358,6 @@ class VatRates
 		],
 	];
 
-
 	/** @var DateTimeImmutable */
 	private $now;
 
diff --git a/tests/VatCalculatorTest.php b/tests/VatCalculatorTest.php
index c5ab19a..966b08e 100644
--- a/tests/VatCalculatorTest.php
+++ b/tests/VatCalculatorTest.php
@@ -151,7 +151,7 @@ public function testValidateVatNumberThrowsExceptionOnInvalidCountry(): void
 	}
 
 
-		public function testCanValidateValidVatNumberWithRequesterVatNumber()
+	public function testCanValidateValidVatNumberWithRequesterVatNumber()
 	{
 		$result = new stdClass();
 		$result->valid = true;