diff --git a/.gitignore b/.gitignore
index 394c1d5..78f5fba 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,6 +4,7 @@
 !/**/.gitkeep
 !/.idea/**
 !/config/**
+!/phpstan.neon
 !/scripts/**
 !/web/modules/custom/**
 !/web/sites/default/environments/settings.*.php
diff --git a/composer.json b/composer.json
index e5f1ee9..e69b8bc 100644
--- a/composer.json
+++ b/composer.json
@@ -34,7 +34,10 @@
     },
     "require-dev": {
         "dealerdirect/phpcodesniffer-composer-installer": "^0.6.2",
-        "drupal/coder": "^8.3"
+        "drupal/coder": "^8.3",
+        "mglaman/phpstan-drupal": "^0.12.3",
+        "phpstan/phpstan": "^0.12.19",
+        "phpstan/phpstan-deprecation-rules": "^0.12.2"
     },
     "conflict": {
         "drupal/drupal": "*"
diff --git a/composer.lock b/composer.lock
index 47eca69..d94fa0a 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": "7774bc7cd069993030bd31b9913bf6f2",
+    "content-hash": "048aa398777f70ad3f8d134435feee84",
     "packages": [
         {
             "name": "asm89/stack-cors",
@@ -6503,6 +6503,343 @@
             ],
             "time": "2020-03-08T19:03:35+00:00"
         },
+        {
+            "name": "mglaman/phpstan-drupal",
+            "version": "0.12.3",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/mglaman/phpstan-drupal.git",
+                "reference": "c72367d12498c9f5d3738852d4089b4570690a55"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/mglaman/phpstan-drupal/zipball/c72367d12498c9f5d3738852d4089b4570690a55",
+                "reference": "c72367d12498c9f5d3738852d4089b4570690a55",
+                "shasum": ""
+            },
+            "require": {
+                "nette/finder": "^2.5",
+                "php": "^7.1",
+                "phpstan/phpstan": "^0.12.0",
+                "symfony/yaml": "~3.4.5|^4.2",
+                "webflo/drupal-finder": "^1.2"
+            },
+            "require-dev": {
+                "composer/installers": "^1.6",
+                "drupal/core-recommended": "^8.8@alpha",
+                "drush/drush": "^9.6",
+                "phpstan/phpstan-deprecation-rules": "~0.12.0",
+                "phpstan/phpstan-strict-rules": "^0.12.0",
+                "phpunit/phpunit": "^7.5",
+                "squizlabs/php_codesniffer": "^3.3"
+            },
+            "suggest": {
+                "phpstan/phpstan-deprecation-rules": "For catching deprecations, especially in Drupal core."
+            },
+            "type": "phpstan-extension",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "0.12-dev"
+                },
+                "installer-paths": {
+                    "tests/fixtures/drupal/core": [
+                        "type:drupal-core"
+                    ],
+                    "tests/fixtures/drupal/libraries/{$name}": [
+                        "type:drupal-library"
+                    ],
+                    "tests/fixtures/drupal/modules/contrib/{$name}": [
+                        "type:drupal-module"
+                    ],
+                    "tests/fixtures/drupal/profiles/contrib/{$name}": [
+                        "type:drupal-profile"
+                    ],
+                    "tests/fixtures/drupal/themes/contrib/{$name}": [
+                        "type:drupal-theme"
+                    ]
+                },
+                "phpstan": {
+                    "includes": [
+                        "extension.neon"
+                    ]
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "PHPStan\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Matt Glaman",
+                    "email": "nmd.matt@gmail.com"
+                }
+            ],
+            "description": "Drupal extension and rules for PHPStan",
+            "funding": [
+                {
+                    "url": "https://github.com/mglaman",
+                    "type": "github"
+                },
+                {
+                    "url": "https://liberapay.com/mglaman",
+                    "type": "liberapay"
+                }
+            ],
+            "time": "2020-03-31T19:03:49+00:00"
+        },
+        {
+            "name": "nette/finder",
+            "version": "v2.5.2",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/nette/finder.git",
+                "reference": "4ad2c298eb8c687dd0e74ae84206a4186eeaed50"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/nette/finder/zipball/4ad2c298eb8c687dd0e74ae84206a4186eeaed50",
+                "reference": "4ad2c298eb8c687dd0e74ae84206a4186eeaed50",
+                "shasum": ""
+            },
+            "require": {
+                "nette/utils": "^2.4 || ^3.0",
+                "php": ">=7.1"
+            },
+            "conflict": {
+                "nette/nette": "<2.2"
+            },
+            "require-dev": {
+                "nette/tester": "^2.0",
+                "phpstan/phpstan": "^0.12",
+                "tracy/tracy": "^2.3"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "2.5-dev"
+                }
+            },
+            "autoload": {
+                "classmap": [
+                    "src/"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "BSD-3-Clause",
+                "GPL-2.0",
+                "GPL-3.0"
+            ],
+            "authors": [
+                {
+                    "name": "David Grudl",
+                    "homepage": "https://davidgrudl.com"
+                },
+                {
+                    "name": "Nette Community",
+                    "homepage": "https://nette.org/contributors"
+                }
+            ],
+            "description": "🔍 Nette Finder: find files and directories with an intuitive API.",
+            "homepage": "https://nette.org",
+            "keywords": [
+                "filesystem",
+                "glob",
+                "iterator",
+                "nette"
+            ],
+            "time": "2020-01-03T20:35:40+00:00"
+        },
+        {
+            "name": "nette/utils",
+            "version": "v3.1.1",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/nette/utils.git",
+                "reference": "2c17d16d8887579ae1c0898ff94a3668997fd3eb"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/nette/utils/zipball/2c17d16d8887579ae1c0898ff94a3668997fd3eb",
+                "reference": "2c17d16d8887579ae1c0898ff94a3668997fd3eb",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=7.1"
+            },
+            "require-dev": {
+                "nette/tester": "~2.0",
+                "phpstan/phpstan": "^0.12",
+                "tracy/tracy": "^2.3"
+            },
+            "suggest": {
+                "ext-gd": "to use Image",
+                "ext-iconv": "to use Strings::webalize() and toAscii()",
+                "ext-intl": "to use Strings::webalize(), toAscii(), normalize() and compare()",
+                "ext-json": "to use Nette\\Utils\\Json",
+                "ext-mbstring": "to use Strings::lower() etc...",
+                "ext-tokenizer": "to use Nette\\Utils\\Reflection::getUseStatements()",
+                "ext-xml": "to use Strings::length() etc. when mbstring is not available"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "3.1-dev"
+                }
+            },
+            "autoload": {
+                "classmap": [
+                    "src/"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "BSD-3-Clause",
+                "GPL-2.0-only",
+                "GPL-3.0-only"
+            ],
+            "authors": [
+                {
+                    "name": "David Grudl",
+                    "homepage": "https://davidgrudl.com"
+                },
+                {
+                    "name": "Nette Community",
+                    "homepage": "https://nette.org/contributors"
+                }
+            ],
+            "description": "🛠 Nette Utils: lightweight utilities for string & array manipulation, image handling, safe JSON encoding/decoding, validation, slug or strong password generating etc.",
+            "homepage": "https://nette.org",
+            "keywords": [
+                "array",
+                "core",
+                "datetime",
+                "images",
+                "json",
+                "nette",
+                "paginator",
+                "password",
+                "slugify",
+                "string",
+                "unicode",
+                "utf-8",
+                "utility",
+                "validation"
+            ],
+            "time": "2020-02-09T14:10:55+00:00"
+        },
+        {
+            "name": "phpstan/phpstan",
+            "version": "0.12.19",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/phpstan/phpstan.git",
+                "reference": "054f6d76b12ba9a6c13a5a8d5fcdf51219615f4d"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/phpstan/phpstan/zipball/054f6d76b12ba9a6c13a5a8d5fcdf51219615f4d",
+                "reference": "054f6d76b12ba9a6c13a5a8d5fcdf51219615f4d",
+                "shasum": ""
+            },
+            "require": {
+                "php": "^7.1"
+            },
+            "conflict": {
+                "phpstan/phpstan-shim": "*"
+            },
+            "bin": [
+                "phpstan",
+                "phpstan.phar"
+            ],
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "0.12-dev"
+                }
+            },
+            "autoload": {
+                "files": [
+                    "bootstrap.php"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "description": "PHPStan - PHP Static Analysis Tool",
+            "funding": [
+                {
+                    "url": "https://github.com/ondrejmirtes",
+                    "type": "github"
+                },
+                {
+                    "url": "https://www.patreon.com/phpstan",
+                    "type": "patreon"
+                },
+                {
+                    "url": "https://tidelift.com/funding/github/packagist/phpstan/phpstan",
+                    "type": "tidelift"
+                }
+            ],
+            "time": "2020-04-19T20:35:10+00:00"
+        },
+        {
+            "name": "phpstan/phpstan-deprecation-rules",
+            "version": "0.12.2",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/phpstan/phpstan-deprecation-rules.git",
+                "reference": "51d21a83b97e539e1fc56c1ce42ac0f187407fb6"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/phpstan/phpstan-deprecation-rules/zipball/51d21a83b97e539e1fc56c1ce42ac0f187407fb6",
+                "reference": "51d21a83b97e539e1fc56c1ce42ac0f187407fb6",
+                "shasum": ""
+            },
+            "require": {
+                "php": "~7.1",
+                "phpstan/phpstan": "^0.12"
+            },
+            "require-dev": {
+                "consistence/coding-standard": "^3.0.1",
+                "dealerdirect/phpcodesniffer-composer-installer": "^0.4.4",
+                "jakub-onderka/php-parallel-lint": "^1.0",
+                "localheinz/composer-normalize": "^1.3.0",
+                "phing/phing": "^2.16.0",
+                "phpstan/phpstan-phpunit": "^0.12",
+                "phpunit/phpunit": "^7.0",
+                "slevomat/coding-standard": "^4.5.2"
+            },
+            "type": "phpstan-extension",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "0.12-dev"
+                },
+                "phpstan": {
+                    "includes": [
+                        "rules.neon"
+                    ]
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "PHPStan\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "description": "PHPStan rules for detecting usage of deprecated classes, methods, properties, constants and traits.",
+            "time": "2020-01-12T16:25:40+00:00"
+        },
         {
             "name": "squizlabs/php_codesniffer",
             "version": "3.5.4",
diff --git a/phpstan.neon b/phpstan.neon
new file mode 100644
index 0000000..85d00f4
--- /dev/null
+++ b/phpstan.neon
@@ -0,0 +1,12 @@
+parameters:
+  level: 7
+  paths:
+    - web/modules/custom
+    - web/themes/custom
+  excludes_analyse:
+    - *Test.php
+    - *TestBase.php
+  checkMissingIterableValueType: false
+includes:
+  - vendor/mglaman/phpstan-drupal/extension.neon
+  - vendor/phpstan/phpstan-deprecation-rules/rules.neon