diff --git a/.editorconfig b/.editorconfig
new file mode 100644
index 0000000..3e3a70c
--- /dev/null
+++ b/.editorconfig
@@ -0,0 +1,57 @@
+# EditorConfig is awesome: http://EditorConfig.org
+
+# top-most EditorConfig file
+root = true
+
+# Unix-style newlines with a newline ending every file
+[*]
+charset = utf-8
+end_of_line = lf
+indent_style = space
+indent_size = 4
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+# TS/JS-Files
+[*.{ts,js,vue}]
+indent_size = 4
+indent_style = tab
+
+# JSON-Files
+[*.json]
+indent_style = tab
+
+# ReST-Files
+[*.rst]
+indent_size = 4
+max_line_length = 80
+
+# YAML-Files
+[*.{yaml,yml}]
+indent_size = 2
+
+# NEON-Files
+[*.neon]
+indent_size = 2
+indent_style = tab
+
+# package.json
+[package.json]
+indent_size = 2
+
+# TypoScript
+[*.{typoscript,tsconfig}]
+indent_size = 2
+
+# XLF-Files
+[*.xlf]
+indent_style = tab
+
+# SQL-Files
+[*.sql]
+indent_style = tab
+indent_size = 2
+
+# .htaccess
+[{_.htaccess,.htaccess}]
+indent_style = tab
diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 0000000..85809a0
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1,5 @@
+/.editorconfig export-ignore
+/.gitignore export-ignore
+/.gitattributes export-ignore
+/.php-cs-fixer.php export-ignore
+/.phpstan.neon export-ignore
diff --git a/.gitignore b/.gitignore
index a1ee133..04fc4e6 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,3 @@
-/build/
 /composer.lock
-/.php_cs.cache
-/public/
\ No newline at end of file
+/vendor/
+/public/
diff --git a/.php-cs-fixer.php b/.php-cs-fixer.php
new file mode 100644
index 0000000..df7b827
--- /dev/null
+++ b/.php-cs-fixer.php
@@ -0,0 +1,10 @@
+<?php
+
+$finder = PhpCsFixer\Finder::create()
+    ->in('Classes')
+    ->in('Configuration');
+
+$config = \TYPO3\CodingStandards\CsFixerConfig::create();
+return $config
+    ->setUsingCache(false)
+    ->setFinder($finder);
diff --git a/Classes/Controller/SuggestReceiver.php b/Classes/Controller/SuggestReceiver.php
index aef84f9..57fb342 100644
--- a/Classes/Controller/SuggestReceiver.php
+++ b/Classes/Controller/SuggestReceiver.php
@@ -1,5 +1,7 @@
 <?php
+
 declare(strict_types=1);
+
 namespace B13\Tag\Controller;
 
 /*
@@ -14,21 +16,14 @@
 use Psr\Http\Message\ResponseInterface;
 use Psr\Http\Message\ServerRequestInterface;
 use TYPO3\CMS\Core\Http\JsonResponse;
-use TYPO3\CMS\Core\Utility\GeneralUtility;
 
-/**
- * Form Engine helper to find suitable tags to select from.
- */
 class SuggestReceiver
 {
-    /**
-     * @var TagRepository
-     */
-    protected $tagRepository;
+    protected TagRepository $tagRepository;
 
-    public function __construct()
+    public function __construct(TagRepository $tagRepository)
     {
-        $this->tagRepository = GeneralUtility::makeInstance(TagRepository::class);
+        $this->tagRepository = $tagRepository;
     }
 
     public function findSuitableTags(ServerRequestInterface $request): ResponseInterface
@@ -39,6 +34,7 @@ public function findSuitableTags(ServerRequestInterface $request): ResponseInter
         } else {
             $tags = [];
         }
+
         return new JsonResponse($tags);
     }
-}
\ No newline at end of file
+}
diff --git a/Classes/Domain/Repository/TagRepository.php b/Classes/Domain/Repository/TagRepository.php
index e270e0c..66bff6f 100644
--- a/Classes/Domain/Repository/TagRepository.php
+++ b/Classes/Domain/Repository/TagRepository.php
@@ -1,5 +1,7 @@
 <?php
+
 declare(strict_types=1);
+
 namespace B13\Tag\Domain\Repository;
 
 /*
@@ -12,26 +14,29 @@
 
 use TYPO3\CMS\Core\Database\Connection;
 use TYPO3\CMS\Core\Database\ConnectionPool;
-use TYPO3\CMS\Core\Utility\GeneralUtility;
 
 /**
  * Abstraction layer to keep all tag DB queries within this PHP class.
  */
 class TagRepository
 {
-    private string $tableName = 'sys_tag';
+    private const TABLE_NAME = 'sys_tag';
+
+    private ConnectionPool $connectionPool;
+
+    public function __construct(ConnectionPool $connectionPool)
+    {
+        $this->connectionPool = $connectionPool;
+    }
 
     public function findRecordsForTagNames(array $tagNames): array
     {
-        $queryBuilder = $this->getConnection()->createQueryBuilder();
+        $queryBuilder = $this->connectionPool->getQueryBuilderForTable(self::TABLE_NAME);
         $stmt = $queryBuilder
             ->select('*')
-            ->from($this->tableName)
+            ->from(self::TABLE_NAME)
             ->where(
-                $queryBuilder->expr()->in(
-                    'name',
-                    $queryBuilder->createNamedParameter($tagNames, Connection::PARAM_STR_ARRAY)
-                )
+                $queryBuilder->expr()->in('name', $queryBuilder->createNamedParameter($tagNames, Connection::PARAM_STR_ARRAY))
             )
             ->executeQuery();
 
@@ -39,33 +44,36 @@ public function findRecordsForTagNames(array $tagNames): array
         while ($row = $stmt->fetchAssociative()) {
             $mappedItems[$row['name']] = $row['uid'];
         }
+
         return $mappedItems;
     }
 
-    public function add(string $tagName, int $pid = 0)
+    public function add(string $tagName, int $pid = 0): string
     {
-        $conn = $this->getConnection();
-        $conn->insert($this->tableName, ['name' => $tagName, 'pid' => $pid, 'createdon' => $GLOBALS['EXEC_TIME']]);
+        $conn = $this->connectionPool->getConnectionForTable(self::TABLE_NAME);
+        $conn->insert(
+            self::TABLE_NAME,
+            [
+                'name' => $tagName,
+                'pid' => $pid,
+                'createdon' => $GLOBALS['EXEC_TIME'],
+            ]
+        );
+
         return $conn->lastInsertId();
     }
 
     /**
      * Simple query for looking for tags that contain the search word. No multi-word / and/or search implemented yet.
-     *
-     * @param string $searchWord
-     * @return array
      */
     public function search(string $searchWord): array
     {
-        $queryBuilder = $this->getConnection()->createQueryBuilder();
+        $queryBuilder = $this->connectionPool->getQueryBuilderForTable(self::TABLE_NAME);
         $stmt = $queryBuilder
             ->select('*')
-            ->from($this->tableName)
+            ->from(self::TABLE_NAME)
             ->where(
-                $queryBuilder->expr()->like(
-                    'name',
-                    $queryBuilder->createNamedParameter('%' . $queryBuilder->escapeLikeWildcards($searchWord) . '%')
-                )
+                $queryBuilder->expr()->like('name', $queryBuilder->createNamedParameter('%' . $queryBuilder->escapeLikeWildcards($searchWord) . '%'))
             )
             ->executeQuery();
 
@@ -73,14 +81,9 @@ public function search(string $searchWord): array
         while ($row = $stmt->fetchAssociative()) {
             $items[] = [
                 'value' => (int)$row['uid'],
-                'name' => $row['name']
+                'name' => $row['name'],
             ];
         }
         return $items;
     }
-
-    private function getConnection(): Connection
-    {
-        return GeneralUtility::makeInstance(ConnectionPool::class)->getConnectionForTable($this->tableName);
-    }
 }
diff --git a/Classes/Form/TagListElement.php b/Classes/Form/TagListElement.php
index ccb30cd..a31696f 100644
--- a/Classes/Form/TagListElement.php
+++ b/Classes/Form/TagListElement.php
@@ -1,5 +1,7 @@
 <?php
+
 declare(strict_types=1);
+
 namespace B13\Tag\Form;
 
 /*
@@ -11,9 +13,9 @@
  */
 
 use TYPO3\CMS\Backend\Form\Element\AbstractFormElement;
+use TYPO3\CMS\Backend\Form\NodeFactory;
 use TYPO3\CMS\Backend\Routing\UriBuilder;
 use TYPO3\CMS\Backend\Utility\BackendUtility;
-use TYPO3\CMS\Core\Information\Typo3Version;
 use TYPO3\CMS\Core\Page\JavaScriptModuleInstruction;
 use TYPO3\CMS\Core\Utility\GeneralUtility;
 use TYPO3\CMS\Core\Utility\StringUtility;
@@ -23,7 +25,17 @@
  */
 class TagListElement extends AbstractFormElement
 {
-    public function render()
+    private UriBuilder $uriBuilder;
+
+    // ToDo: when v12 is dropped add DI with only UriBuilder
+    public function __construct()
+    {
+        // ToDo: remove manual instances of properties when v12 is dropped
+        $this->uriBuilder = GeneralUtility::makeInstance(UriBuilder::class);
+        $this->nodeFactory = GeneralUtility::makeInstance(NodeFactory::class);
+    }
+
+    public function render(): array
     {
         $resultArray = $this->initializeResultArray();
         $selectedItems = $this->data['parameterArray']['itemFormElValue'] ?? [];
@@ -86,37 +98,17 @@ public function render()
             ];
         }
 
-        $ajaxUrl = GeneralUtility::makeInstance(UriBuilder::class)->buildUriFromRoute('ajax_tag_suggest_tags');
+        $ajaxUrl = $this->uriBuilder->buildUriFromRoute('ajax_tag_suggest_tags');
         $resultArray['html'] = implode(LF, $html);
 
         $resultArray['stylesheetFiles'][] = 'EXT:tag/Resources/Public/StyleSheets/tagsinput.css';
-        if ((new Typo3Version())->getMajorVersion() < 12) {
-            $resultArray['requireJsModules'][] = [
-                'TYPO3/CMS/Tag/TagsInputElement' => 'function(TagsInputElement) {
-                new TagsInputElement("' . $tagsId . '", {
-                    itemValue: function(item) {
-                        return item.value || item;
-                    },
-                    itemText: function(item) {
-                        return item.name || item;
-                    },
-                    items: ' . json_encode($items) . ',
-                    typeahead: {
-                        minLength: 2,
-                        source: function(query) {
-                            var url = ' . GeneralUtility::quoteJSvalue($ajaxUrl) . ' + "&q=" + query;
-                            return $.getJSON(url);
-                        }
-                    }
-                });
-            }'
-            ];
-        } else {
-            $resultArray['javaScriptModules'][] = JavaScriptModuleInstruction::create(
-                '@b13/tag/tags-input-element.js',
-            )->instance($tagsId, $items, (string)$ajaxUrl);
-        }
+        $resultArray['javaScriptModules'][] = JavaScriptModuleInstruction::create('@b13/tag/tags-input-element.js')->instance($tagsId, $items, (string)$ajaxUrl);
 
         return $resultArray;
     }
+
+    public function setData(array $data): void
+    {
+        $this->data = $data;
+    }
 }
diff --git a/Classes/Persistence/PrepareTagItems.php b/Classes/Persistence/PrepareTagItems.php
index 28d9ee4..890580a 100644
--- a/Classes/Persistence/PrepareTagItems.php
+++ b/Classes/Persistence/PrepareTagItems.php
@@ -1,5 +1,7 @@
 <?php
+
 declare(strict_types=1);
+
 namespace B13\Tag\Persistence;
 
 /*
@@ -10,33 +12,26 @@
  * of the License, or any later version.
  */
 
-
 use B13\Tag\Domain\Repository\TagRepository;
 use B13\Tag\TcaHelper;
 use TYPO3\CMS\Backend\Utility\BackendUtility;
 use TYPO3\CMS\Core\DataHandling\DataHandler;
-use TYPO3\CMS\Core\Utility\GeneralUtility;
 use TYPO3\CMS\Core\Utility\MathUtility;
 
 class PrepareTagItems
 {
     protected TagRepository $tagRepository;
 
-    public function __construct()
+    public function __construct(TagRepository $tagRepository)
     {
-        $this->tagRepository = GeneralUtility::makeInstance(TagRepository::class);
+        $this->tagRepository = $tagRepository;
     }
 
     /**
      * DataHandler hook to create tags automatically if they don't exist yet. This way, a clean list of
      * IDs is entered to DataHandler.
-     *
-     * @param $incomingFieldArray
-     * @param $table
-     * @param $id
-     * @param DataHandler $dataHandler
      */
-    public function processDatamap_preProcessFieldArray(&$incomingFieldArray, $table, $id, DataHandler $dataHandler)
+    public function processDatamap_preProcessFieldArray(array &$incomingFieldArray, string $table, string $id, DataHandler $dataHandler)
     {
         $relevantFields = (new TcaHelper())->findTagFieldsForTable($table);
         if (empty($relevantFields)) {
@@ -77,10 +72,6 @@ public function processDatamap_preProcessFieldArray(&$incomingFieldArray, $table
 
     /**
      * See what tags are already in the database and add missing tags, and map the tag names to the IDs.
-     *
-     * @param array $tags
-     * @param int $pid
-     * @return array
      */
     protected function normalizeValuesAndMapToIds(array $tags, int $pid): array
     {
diff --git a/Classes/TcaHelper.php b/Classes/TcaHelper.php
index 65da317..6276969 100644
--- a/Classes/TcaHelper.php
+++ b/Classes/TcaHelper.php
@@ -1,5 +1,7 @@
 <?php
+
 declare(strict_types=1);
+
 namespace B13\Tag;
 
 /*
@@ -10,12 +12,22 @@
  * of the License, or any later version.
  */
 
+use TYPO3\CMS\Core\Information\Typo3Version;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
 /**
  * Helper functionality to quickly work with tags without having to configure TCA, this also allows for "tag"
  * to change implementation without having users to modify their code.
  */
 class TcaHelper
 {
+    private Typo3Version $typo3Version;
+
+    public function __construct()
+    {
+        $this->typo3Version = GeneralUtility::makeInstance(Typo3Version::class);
+    }
+
     public function buildFieldConfiguration(string $table, string $fieldName, array $fieldConfigurationOverride = null): array
     {
         $fieldConfiguration = [
@@ -27,13 +39,17 @@ public function buildFieldConfiguration(string $table, string $fieldName, array
             'items' => [],
             'foreign_table' => 'sys_tag',
             'MM' => 'sys_tag_mm',
-            'MM_hasUidField' => true,
             'MM_opposite_field' => 'items',
             'MM_match_fields' => [
                 'tablenames' => $table,
                 'fieldname' => $fieldName,
             ],
         ];
+
+        if ($this->typo3Version->getMajorVersion() === 12) {
+            $fieldConfiguration['MM_hasUidField'] = true;
+        }
+
         // Merge changes to TCA configuration
         if (!empty($fieldConfigurationOverride)) {
             $fieldConfiguration = array_replace_recursive(
@@ -55,9 +71,6 @@ public function buildFieldConfiguration(string $table, string $fieldName, array
 
     /**
      * Shorthand function to identify all fields that have tags based on the foreign_table field.
-     *
-     * @param string $table
-     * @return array
      */
     public function findTagFieldsForTable(string $table): array
     {
diff --git a/Configuration/Backend/AjaxRoutes.php b/Configuration/Backend/AjaxRoutes.php
index 06b74f0..619256b 100644
--- a/Configuration/Backend/AjaxRoutes.php
+++ b/Configuration/Backend/AjaxRoutes.php
@@ -3,6 +3,6 @@
 return [
     'tag_suggest_tags' => [
         'path' => '/tag/suggest',
-        'target' => B13\Tag\Controller\SuggestReceiver::class . '::findSuitableTags'
+        'target' => B13\Tag\Controller\SuggestReceiver::class . '::findSuitableTags',
     ],
-];
\ No newline at end of file
+];
diff --git a/Configuration/Services.yaml b/Configuration/Services.yaml
new file mode 100644
index 0000000..7fa2540
--- /dev/null
+++ b/Configuration/Services.yaml
@@ -0,0 +1,14 @@
+services:
+  _defaults:
+    autowire: true
+    autoconfigure: true
+    public: false
+
+  B13\Tag\:
+    resource: '../Classes/*'
+
+  B13\Tag\Controller\SuggestReceiver:
+    public: true
+
+  B13\Tag\Persistence\PrepareTagItems:
+    public: true
diff --git a/Configuration/TCA/sys_tag.php b/Configuration/TCA/sys_tag.php
index ae4ad3c..a70785c 100644
--- a/Configuration/TCA/sys_tag.php
+++ b/Configuration/TCA/sys_tag.php
@@ -1,20 +1,21 @@
 <?php
+
 return [
     'ctrl' => [
         'title' => 'LLL:EXT:tag/Resources/Private/Language/locallang_tca.xlf:sys_tag',
         'label' => 'name',
         'tstamp' => 'updatedon',
         'crdate' => 'createdon',
-        'cruser_id' => 'createdby',
         'delete' => 'deleted',
         'default_sortby' => 'name',
         'rootLevel' => -1,
         'searchFields' => 'name',
         'typeicon_classes' => [
-            'default' => 'mimetypes-x-sys_category'
+            'default' => 'mimetypes-x-sys_category',
         ],
         'security' => [
             'ignoreRootLevelRestriction' => true,
+            'ignorePageTypeRestriction' => true,
         ],
     ],
     'types' => [
@@ -30,14 +31,14 @@
             'config' => [
                 'type' => 'input',
                 'width' => 200,
-                'eval' => 'trim,required'
-            ]
+                'eval' => 'trim',
+                'required' => true,
+            ],
         ],
         'items' => [
             'label' => 'LLL:EXT:tag/Resources/Private/Language/locallang_tca.xlf:sys_tag.items',
             'config' => [
                 'type' => 'group',
-                'internal_type' => 'db',
                 'allowed' => '*',
                 'MM' => 'sys_tag_mm',
                 'MM_oppositeUsage' => [],
diff --git a/Resources/Public/StyleSheets/tagsinput.css b/Resources/Public/StyleSheets/tagsinput.css
index 61aed11..87ae8ec 100644
--- a/Resources/Public/StyleSheets/tagsinput.css
+++ b/Resources/Public/StyleSheets/tagsinput.css
@@ -37,7 +37,7 @@
 }
 .bootstrap-tagsinput .tag {
     margin-right: 2px;
-    color: white;
+    color: #343434;
 }
 .bootstrap-tagsinput .tag [data-role="remove"] {
     margin-left: 8px;
@@ -52,4 +52,15 @@
 }
 .bootstrap-tagsinput .tag [data-role="remove"]:hover:active {
     box-shadow: inset 0 3px 5px rgba(0, 0, 0, 0.125);
-}
\ No newline at end of file
+}
+
+@media (prefers-color-scheme: dark) {
+    .bootstrap-tagsinput {
+        background: #000;
+        color: #fff;
+    }
+
+    .bootstrap-tagsinput .tag {
+        color: #fff;
+    }
+}
diff --git a/composer.json b/composer.json
index 489ff25..d5bc55a 100644
--- a/composer.json
+++ b/composer.json
@@ -3,14 +3,10 @@
 	"type": "typo3-cms-extension",
 	"description": "Manage tags in TYPO3 Core",
 	"license": "GPL-2.0-or-later",
-	"config": {
-		"vendor-dir": "build/vendor"
-	},
 	"require": {
 		"php": "^7.4 || ^8.0",
-		"doctrine/dbal": "^2.13 || ^3.0",
-		"typo3/cms-core": "^11.0 || ^12.0",
-		"typo3/cms-backend": "^11.0 || ^12.0"
+		"typo3/cms-core": "^12.0 || ^13.0",
+		"typo3/cms-backend": "^12.0 || ^13.0"
 	},
 	"extra": {
 		"typo3/cms": {
@@ -21,5 +17,17 @@
 		"psr-4": {
 			"B13\\Tag\\": "Classes/"
 		}
+	},
+	"require-dev": {
+		"friendsofphp/php-cs-fixer": "^3.68",
+		"phpstan/phpstan": "^1.12",
+		"saschaegerer/phpstan-typo3": "^1.10",
+		"typo3/coding-standards": "^0.8.0"
+	},
+	"config": {
+		"allow-plugins": {
+			"typo3/cms-composer-installers": true,
+			"typo3/class-alias-loader": true
+		}
 	}
 }
diff --git a/ext_emconf.php b/ext_emconf.php
deleted file mode 100755
index 6d03321..0000000
--- a/ext_emconf.php
+++ /dev/null
@@ -1,19 +0,0 @@
-<?php
-
-$EM_CONF[$_EXTKEY] = [
-    'title' => 'Tags and Keywords',
-    'description' => 'Builds a tag bundle package to allow tags to be handled and added.',
-    'category' => 'be',
-    'author' => 'b13 GmbH',
-    'author_email' => 'typo3@b13.com',
-    'state' => 'stable',
-    'author_company' => '',
-    'version' => '1.2.0',
-    'constraints' => [
-        'depends' => [
-            'typo3' => '11.0.0-12.4.99',
-        ],
-        'conflicts' => [],
-        'suggests' => [],
-    ],
-];
diff --git a/ext_localconf.php b/ext_localconf.php
index 42ab933..205accf 100644
--- a/ext_localconf.php
+++ b/ext_localconf.php
@@ -3,7 +3,7 @@
 
 $GLOBALS['TYPO3_CONF_VARS']['SYS']['formEngine']['nodeRegistry'][1433089350] = [
     'nodeName' => 'tagList',
-    'priority' => 60,
+    'priority' => 40,
     'class' => \B13\Tag\Form\TagListElement::class,
 ];
 $GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['t3lib/class.t3lib_tcemain.php']['processDatamapClass']['b13/tag'] = \B13\Tag\Persistence\PrepareTagItems::class;
diff --git a/ext_tables.sql b/ext_tables.sql
index 8c88c36..23d7211 100755
--- a/ext_tables.sql
+++ b/ext_tables.sql
@@ -4,7 +4,7 @@ CREATE TABLE sys_tag (
 );
 
 CREATE TABLE sys_tag_mm (
-    uid int(11) NOT NULL auto_increment,
+	uid int(11) NOT NULL auto_increment,
 	uid_local int(11) DEFAULT '0' NOT NULL,
 	uid_foreign int(11) DEFAULT '0' NOT NULL,
 	tablenames varchar(255) DEFAULT '' NOT NULL,
@@ -12,7 +12,7 @@ CREATE TABLE sys_tag_mm (
 	sorting int(11) DEFAULT '0' NOT NULL,
 	sorting_foreign int(11) DEFAULT '0' NOT NULL,
 
-    PRIMARY KEY (uid),
+	PRIMARY KEY (uid),
 	KEY uid_local_foreign (uid_local,uid_foreign),
 	KEY uid_foreign_tablefield (uid_foreign,tablenames(40),fieldname(3),sorting_foreign)
 );
diff --git a/phpstan.neon b/phpstan.neon
new file mode 100644
index 0000000..5ceba99
--- /dev/null
+++ b/phpstan.neon
@@ -0,0 +1,16 @@
+includes:
+    - vendor/phpstan/phpstan/conf/bleedingEdge.neon
+    - vendor/saschaegerer/phpstan-typo3/extension.neon
+
+parameters:
+  level: 5
+
+  paths:
+    - %currentWorkingDirectory%/
+
+  excludePaths:
+    analyseAndScan:
+      - */node_modules/*
+      - vendor/*
+      - public/*
+      - ./.php-cs-fixer.php