TYPO3 Dual-Version Development: v13 & v14

Strategy: Write code that works on both TYPO3 v13 and v14, with v14 as the preferred target. All patterns in this skill are designed for dual-version compatibility.

TYPO3 API First: Always use TYPO3’s built-in APIs, core features, and established conventions before creating custom implementations. Do not reinvent what TYPO3 already provides. Always verify that the APIs and methods you use exist and are not deprecated in your target TYPO3 version (v13 or v14) by checking the official TYPO3 documentation.

1. Version Strategy

Target: TYPO3 v13 and v14

Best Practice: Target both v13 and v14 for maximum compatibility. New projects should prefer v14.

Version Constraints

<?php
// ext_emconf.php - Dual version support
$EM_CONF[$_EXTKEY] = [
    'title' => 'My Extension',
    'version' => '2.0.0',
    'state' => 'stable',
    'constraints' => [
        'depends' => [
            'typo3' => '13.0.0-14.99.99',
            'php' => '8.2.0-8.4.99',
        ],
        'conflicts' => [],
        'suggests' => [],
    ],
];

// composer.json - Dual version support
{
    "name": "vendor/my-extension",
    "type": "typo3-cms-extension",
    "require": {
        "php": "^8.2",
        "typo3/cms-core": "^13.0 || ^14.0"
    },
    "extra": {
        "typo3/cms": {
            "extension-key": "my_extension"
        }
    }
}

2. PHP Requirements

Minimum PHP Version: 8.2

Both v13 and v14 require PHP 8.2+. Use modern PHP features:

<?php
declare(strict_types=1);

namespace Vendor\Extension\Service;

// ✅ Constructor property promotion (PHP 8.0+)
final class MyService
{
    public function __construct(
        private readonly SomeDependency $dependency,
        private readonly AnotherService $anotherService,
    ) {}
}

// ✅ Named arguments (PHP 8.0+)
$result = $this->doSomething(
    name: 'value',
    options: ['key' => 'value'],
);

// ✅ Match expressions (PHP 8.0+)
$type = match ($input) {
    'a' => 'Type A',
    'b' => 'Type B',
    default => 'Unknown',
};

// ✅ Enums (PHP 8.1+)
enum Status: string
{
    case Draft = 'draft';
    case Published = 'published';
}

3. Controller Patterns (v13/v14 Compatible)

Extbase Action Controller

<?php
declare(strict_types=1);

namespace Vendor\Extension\Controller;

use Psr\Http\Message\ResponseInterface;
use TYPO3\CMS\Extbase\Mvc\Controller\ActionController;
use Vendor\Extension\Domain\Repository\ItemRepository;

final class ItemController extends ActionController
{
    public function __construct(
        private readonly ItemRepository $itemRepository,
    ) {}

    // ✅ Must return ResponseInterface (required since v13)
    public function listAction(): ResponseInterface
    {
        $items = $this->itemRepository->findAll();
        $this->view->assign('items', $items);
        return $this->htmlResponse();
    }

    public function showAction(int $item): ResponseInterface
    {
        $item = $this->itemRepository->findByUid($item);
        $this->view->assign('item', $item);
        return $this->htmlResponse();
    }

    // ✅ JSON response
    public function apiAction(): ResponseInterface
    {
        $data = ['success' => true, 'items' => []];
        return $this->jsonResponse(json_encode($data));
    }

    // ✅ Redirect
    public function createAction(): ResponseInterface
    {
        // Process creation...
        $this->addFlashMessage('Item created');
        return $this->redirect('list');
    }
}

Backend Module Controller

<?php
declare(strict_types=1);

namespace Vendor\Extension\Controller;

use Psr\Http\Message\ResponseInterface;
use Psr\Http\Message\ServerRequestInterface;
use TYPO3\CMS\Backend\Attribute\AsController;
use TYPO3\CMS\Backend\Template\ModuleTemplateFactory;

#[AsController]
final class BackendModuleController
{
    public function __construct(
        private readonly ModuleTemplateFactory $moduleTemplateFactory,
    ) {}

    public function indexAction(ServerRequestInterface $request): ResponseInterface
    {
        $moduleTemplate = $this->moduleTemplateFactory->create($request);
        $moduleTemplate->assign('items', []);
        
        return $moduleTemplate->renderResponse('Backend/Index');
    }
}

4. View & Templating (v13/v14 Compatible)

ViewFactory (Preferred Pattern)

<?php
declare(strict_types=1);

namespace Vendor\Extension\Service;

use Psr\Http\Message\ServerRequestInterface;
use TYPO3\CMS\Core\View\ViewFactoryData;
use TYPO3\CMS\Core\View\ViewFactoryInterface;

final class RenderingService
{
    public function __construct(
        private readonly ViewFactoryInterface $viewFactory,
    ) {}

    public function renderEmail(ServerRequestInterface $request, array $data): string
    {
        $viewFactoryData = new ViewFactoryData(
            templateRootPaths: ['EXT:my_extension/Resources/Private/Templates/Email'],
            partialRootPaths: ['EXT:my_extension/Resources/Private/Partials'],
            layoutRootPaths: ['EXT:my_extension/Resources/Private/Layouts'],
            request: $request,
        );
        
        $view = $this->viewFactory->create($viewFactoryData);
        $view->assignMultiple($data);
        
        return $view->render('Notification');
    }
}

Fluid Template Best Practices

<html xmlns:f="http://typo3.org/ns/TYPO3/CMS/Fluid/ViewHelpers"
      xmlns:core="http://typo3.org/ns/TYPO3/CMS/Core/ViewHelpers"
      data-namespace-typo3-fluid="true">

<f:layout name="Default" />

<f:section name="Main">
    <div class="content">
        <!-- ✅ Auto-escaped output -->
        <h1>{item.title}</h1>
        
        <!-- ✅ Explicit HTML (use with caution) -->
        <f:format.html>{item.bodytext}</f:format.html>
        
        <!-- ✅ Conditional rendering -->
        <f:if condition="{items}">
            <f:then>
                <f:for each="{items}" as="item">
                    <f:render partial="Item" arguments="{item: item}" />
                </f:for>
            </f:then>
            <f:else>
                <p>No items found.</p>
            </f:else>
        </f:if>
        
        <!-- ✅ Link building -->
        <f:link.action action="show" arguments="{item: item.uid}">
            View Details
        </f:link.action>
    </div>
</f:section>

</html>

5. Event System (v13/v14 Compatible)

PSR-14 Event Listeners

PSR-14 events are the standard in both v13 and v14. Always prefer events over hooks.

<?php
declare(strict_types=1);

namespace Vendor\Extension\EventListener;

use TYPO3\CMS\Core\Attribute\AsEventListener;
use TYPO3\CMS\Frontend\Event\ModifyCacheLifetimeForPageEvent;

#[AsEventListener(identifier: 'vendor-extension/modify-cache-lifetime')]
final class ModifyCacheLifetimeListener
{
    public function __invoke(ModifyCacheLifetimeForPageEvent $event): void
    {
        // Reduce cache lifetime for certain pages
        if ($event->getPageId() === 123) {
            $event->setCacheLifetime(300); // 5 minutes
        }
    }
}

Common Events (v13/v14)

Services.yaml Registration

# Configuration/Services.yaml
services:
  _defaults:
    autowire: true
    autoconfigure: true
    public: false

  Vendor\Extension\:
    resource: '../Classes/*'
    exclude:
      - '../Classes/Domain/Model/*'

  # Event listener (alternative to #[AsEventListener] attribute)
  Vendor\Extension\EventListener\MyListener:
    tags:
      - name: event.listener
        identifier: 'vendor-extension/my-listener'

6. Backend Module Registration (v13/v14)

Configuration/Backend/Modules.php

<?php
// Configuration/Backend/Modules.php
return [
    'web_myextension' => [
        'parent' => 'web',
        'position' => ['after' => 'web_info'],
        'access' => 'user,group',
        'iconIdentifier' => 'myextension-module',
        'path' => '/module/web/myextension',
        'labels' => 'LLL:EXT:my_extension/Resources/Private/Language/locallang_mod.xlf',
        'extensionName' => 'MyExtension',
        'controllerActions' => [
            \Vendor\MyExtension\Controller\BackendController::class => [
                'index',
                'list',
                'show',
            ],
        ],
    ],
];

Icon Registration

<?php
// Configuration/Icons.php
return [
    'myextension-module' => [
        'provider' => \TYPO3\CMS\Core\Imaging\IconProvider\SvgIconProvider::class,
        'source' => 'EXT:my_extension/Resources/Public/Icons/module.svg',
    ],
];

7. TCA Configuration (v13/v14 Compatible)

Static TCA Only

In v14, runtime TCA modifications are forbidden. Always use static files:

<?php
// Configuration/TCA/tx_myext_domain_model_item.php
return [
    'ctrl' => [
        'title' => 'LLL:EXT:my_extension/Resources/Private/Language/locallang_db.xlf:tx_myext_domain_model_item',
        'label' => 'title',
        'tstamp' => 'tstamp',
        'crdate' => 'crdate',
        'delete' => 'deleted',
        'enablecolumns' => [
            'disabled' => 'hidden',
            'starttime' => 'starttime',
            'endtime' => 'endtime',
        ],
        'searchFields' => 'title,description',
        'iconIdentifier' => 'myextension-item',
    ],
    'types' => [
        '1' => [
            'showitem' => '
                --div--;LLL:EXT:core/Resources/Private/Language/Form/locallang_tabs.xlf:general,
                    title, description,
                --div--;LLL:EXT:core/Resources/Private/Language/Form/locallang_tabs.xlf:access,
                    hidden, starttime, endtime,
            ',
        ],
    ],
    'columns' => [
        'title' => [
            'label' => 'LLL:EXT:my_extension/Resources/Private/Language/locallang_db.xlf:tx_myext_domain_model_item.title',
            'config' => [
                'type' => 'input',
                'size' => 50,
                'max' => 255,
                'required' => true,
            ],
        ],
        'description' => [
            'label' => 'LLL:EXT:my_extension/Resources/Private/Language/locallang_db.xlf:tx_myext_domain_model_item.description',
            'config' => [
                'type' => 'text',
                'cols' => 40,
                'rows' => 5,
                'enableRichtext' => true,
            ],
        ],
    ],
];

TCA Overrides

<?php
// Configuration/TCA/Overrides/tt_content.php
defined('TYPO3') or die();

\TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addTcaSelectItem(
    'tt_content',
    'CType',
    [
        'label' => 'LLL:EXT:my_extension/Resources/Private/Language/locallang.xlf:ctype.title',
        'value' => 'myextension_element',
        'icon' => 'content-text',
        'group' => 'default',
    ]
);

$GLOBALS['TCA']['tt_content']['types']['myextension_element'] = [
    'showitem' => '
        --div--;LLL:EXT:core/Resources/Private/Language/Form/locallang_tabs.xlf:general,
            --palette--;;general,
            header,
            bodytext,
        --div--;LLL:EXT:core/Resources/Private/Language/Form/locallang_tabs.xlf:access,
            --palette--;;hidden,
    ',
];

8. Database Operations (v13/v14 Compatible)

QueryBuilder

<?php
declare(strict_types=1);

namespace Vendor\Extension\Repository;

use TYPO3\CMS\Core\Database\Connection;
use TYPO3\CMS\Core\Database\ConnectionPool;
use TYPO3\CMS\Core\Database\Query\QueryBuilder;

final class CustomRepository
{
    public function __construct(
        private readonly ConnectionPool $connectionPool,
    ) {}

    public function findByStatus(string $status): array
    {
        $queryBuilder = $this->connectionPool->getQueryBuilderForTable('tx_myext_items');
        
        return $queryBuilder
            ->select('*')
            ->from('tx_myext_items')
            ->where(
                $queryBuilder->expr()->eq(
                    'status',
                    $queryBuilder->createNamedParameter($status)
                )
            )
            ->orderBy('title', 'ASC')
            ->executeQuery()
            ->fetchAllAssociative();
    }

    public function countByPid(int $pid): int
    {
        $queryBuilder = $this->connectionPool->getQueryBuilderForTable('tx_myext_items');
        
        return (int)$queryBuilder
            ->count('uid')
            ->from('tx_myext_items')
            ->where(
                $queryBuilder->expr()->eq(
                    'pid',
                    $queryBuilder->createNamedParameter($pid, Connection::PARAM_INT)
                )
            )
            ->executeQuery()
            ->fetchOne();
    }
}

Extbase Repository

<?php
declare(strict_types=1);

namespace Vendor\Extension\Domain\Repository;

use TYPO3\CMS\Extbase\Persistence\QueryInterface;
use TYPO3\CMS\Extbase\Persistence\Repository;

final class ItemRepository extends Repository
{
    protected $defaultOrderings = [
        'sorting' => QueryInterface::ORDER_ASCENDING,
    ];

    public function findPublished(): array
    {
        $query = $this->createQuery();
        $query->matching(
            $query->logicalAnd(
                $query->equals('hidden', false),
                $query->lessThanOrEqual('starttime', time()),
                $query->logicalOr(
                    $query->equals('endtime', 0),
                    $query->greaterThan('endtime', time())
                )
            )
        );
        
        return $query->execute()->toArray();
    }
}

9. CLI Commands (v13/v14 Compatible)

<?php
declare(strict_types=1);

namespace Vendor\Extension\Command;

use Symfony\Component\Console\Attribute\AsCommand;
use Symfony\Component\Console\Command\Command;
use Symfony\Component\Console\Input\InputArgument;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Input\InputOption;
use Symfony\Component\Console\Output\OutputInterface;
use Symfony\Component\Console\Style\SymfonyStyle;
use TYPO3\CMS\Core\Core\Bootstrap;

#[AsCommand(
    name: 'myext:process',
    description: 'Process items in the extension',
)]
final class ProcessCommand extends Command
{
    protected function configure(): void
    {
        $this
            ->addArgument('type', InputArgument::REQUIRED, 'The type to process')
            ->addOption('force', 'f', InputOption::VALUE_NONE, 'Force processing');
    }

    protected function execute(InputInterface $input, OutputInterface $output): int
    {
        $io = new SymfonyStyle($input, $output);
        
        // Initialize backend for DataHandler operations
        Bootstrap::initializeBackendAuthentication();
        
        $type = $input->getArgument('type');
        $force = $input->getOption('force');
        
        $io->title('Processing: ' . $type);
        
        // Your logic here...
        
        $io->success('Processing completed successfully');
        
        return Command::SUCCESS;
    }
}

Command Registration

# Configuration/Services.yaml
services:
  Vendor\Extension\Command\ProcessCommand:
    tags:
      - name: console.command

10. Testing for Dual-Version Compatibility

PHPUnit Setup

<!-- phpunit.xml -->
<?xml version="1.0" encoding="UTF-8"?>
<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:noNamespaceSchemaLocation="vendor/phpunit/phpunit/phpunit.xsd"
         bootstrap="vendor/typo3/testing-framework/Resources/Core/Build/UnitTestsBootstrap.php"
         colors="true">
    <testsuites>
        <testsuite name="Unit">
            <directory>Tests/Unit</directory>
        </testsuite>
        <testsuite name="Functional">
            <directory>Tests/Functional</directory>
        </testsuite>
    </testsuites>
</phpunit>

Test Both Versions in CI

# .github/workflows/ci.yaml
name: CI

on: [push, pull_request]

jobs:
  test:
    runs-on: ubuntu-latest
    strategy:
      matrix:
        typo3: ['^13.0', '^14.0']
        php: ['8.2', '8.3']
    
    steps:
      - uses: actions/checkout@v4
      
      - name: Setup PHP
        uses: shivammathur/setup-php@v2
        with:
          php-version: ${{ matrix.php }}
          extensions: intl, pdo_mysql
      
      - name: Install dependencies
        run: |
          composer require typo3/cms-core:${{ matrix.typo3 }} --no-update
          composer install --prefer-dist --no-progress
      
      - name: Run tests
        run: vendor/bin/phpunit

11. Upgrade Process

From v12 to v13/v14

# 1. Create backup
ddev snapshot --name=before-upgrade

# 2. Update composer constraints
ddev composer require "typo3/cms-core:^13.0 || ^14.0" --no-update
ddev composer update "typo3/*" --with-all-dependencies

# 3. Run upgrade wizards
ddev typo3 upgrade:list
ddev typo3 upgrade:run

# 4. Clear caches
ddev typo3 cache:flush

# 5. Update database schema
ddev typo3 database:updateschema

# 6. Test thoroughly

12. Resources

• v13 Documentation: https://docs.typo3.org/m/typo3/reference-coreapi/13.4/en-us/
• v14 Documentation: https://docs.typo3.org/m/typo3/reference-coreapi/main/en-us/
• v13 Changelog: https://docs.typo3.org/c/typo3/cms-core/main/en-us/Changelog-13/Index.html
• v14 Changelog: https://docs.typo3.org/c/typo3/cms-core/main/en-us/Changelog-14/Index.html
• TYPO3 Rector: https://github.com/sabbelasichon/typo3-rector

Credits & Attribution

Thanks to Netresearch DTT GmbH for their contributions to the TYPO3 community.