composer require --dev ssch/typo3-rector
# or with DDEV:
ddev composer require --dev ssch/typo3-rector

<?php
declare(strict_types=1);

use Rector\Config\RectorConfig;
use Rector\Set\ValueObject\LevelSetList;
use Rector\ValueObject\PhpVersion;
use Ssch\TYPO3Rector\Set\Typo3LevelSetList;

return RectorConfig::configure()
    ->withPaths([
        __DIR__ . '/packages',
        __DIR__ . '/public/typo3conf/ext',
    ])
    ->withSkip([
        __DIR__ . '/public/typo3conf/ext/*/Resources/',
        __DIR__ . '/public/typo3conf/ext/*/Tests/',
    ])
    ->withPhpVersion(PhpVersion::PHP_82)
    ->withSets([
        LevelSetList::UP_TO_PHP_82,
        Typo3LevelSetList::UP_TO_TYPO3_14,
    ])
    ->withImportNames();

# Show what would be changed
ddev exec vendor/bin/rector process --dry-run

# For specific extension
ddev exec vendor/bin/rector process packages/my_extension --dry-run

# Apply all changes
ddev exec vendor/bin/rector process

# Apply to specific path
ddev exec vendor/bin/rector process packages/my_extension

ddev typo3 cache:flush
ddev composer dump-autoload

<?php
// ext_emconf.php
$EM_CONF[$_EXTKEY] = [
    'title' => 'My Extension',
    'version' => '2.0.0',
    'state' => 'stable',
    'constraints' => [
        'depends' => [
            'typo3' => '14.0.0-14.99.99',
            'php' => '8.2.0-8.4.99',
        ],
        'conflicts' => [],
        'suggests' => [],
    ],
];

// composer.json
{
    "require": {
        "php": "^8.2",
        "typo3/cms-core": "^14.0"
    }
}

<?php
declare(strict_types=1);

use Rector\Config\RectorConfig;
use Ssch\TYPO3Rector\Set\Typo3SetList;

return RectorConfig::configure()
    ->withPaths([__DIR__ . '/packages'])
    ->withSets([
        Typo3SetList::TYPO3_14,
    ]);

<?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 render(ServerRequestInterface $request): string
    {
        $viewFactoryData = new ViewFactoryData(
            templateRootPaths: ['EXT:my_extension/Resources/Private/Templates'],
            partialRootPaths: ['EXT:my_extension/Resources/Private/Partials'],
            layoutRootPaths: ['EXT:my_extension/Resources/Private/Layouts'],
            request: $request,
        );
        
        $view = $this->viewFactory->create($viewFactoryData);
        $view->assign('data', ['key' => 'value']);
        $view->assignMultiple([
            'items' => [],
            'settings' => [],
        ]);
        
        return $view->render('MyTemplate');
    }
}

<?php
declare(strict_types=1);

namespace Vendor\Extension\Controller;

use Psr\Http\Message\ResponseInterface;
use TYPO3\CMS\Extbase\Mvc\Controller\ActionController;

final class ItemController extends ActionController
{
    // ✅ Correct: Return ResponseInterface (required in TYPO3 v14)
    public function listAction(): ResponseInterface
    {
        $items = $this->itemRepository->findAll();
        $this->view->assign('items', $items);
        return $this->htmlResponse();
    }

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

    // ✅ Correct: Redirect
    public function createAction(Item $item): ResponseInterface
    {
        $this->itemRepository->add($item);
        return $this->redirect('list');
    }
}

<?php
declare(strict_types=1);

namespace Vendor\Extension\EventListener;

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

#[AsEventListener(identifier: 'vendor-extension/modify-pagelink')]
final class ModifyPageLinkListener
{
    public function __invoke(ModifyPageLinkConfigurationEvent $event): void
    {
        $configuration = $event->getConfiguration();
        // Modify link configuration
        $event->setConfiguration($configuration);
    }
}

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

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

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

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

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

$GLOBALS['TCA']['tt_content']['types']['myextension_mytype'] = [
    'showitem' => '
        --div--;LLL:EXT:core/Resources/Private/Language/Form/locallang_tabs.xlf:general,
            --palette--;;general,
            header;LLL:EXT:frontend/Resources/Private/Language/locallang_ttc.xlf:header_formlabel,
            bodytext,
        --div--;LLL:EXT:core/Resources/Private/Language/Form/locallang_tabs.xlf:access,
            --palette--;;hidden,
            --palette--;;access,
    ',
    'columnsOverrides' => [
        'bodytext' => [
            'config' => [
                'enableRichtext' => true,
            ],
        ],
    ],
];

# Create backup
ddev snapshot --name=before-migration

# Ensure tests pass
ddev exec vendor/bin/phpunit -c packages/my_extension/Tests/phpunit.xml

# Check deprecation log
tail -f var/log/typo3_deprecations_*.log

<?php
declare(strict_types=1);

use Rector\Config\RectorConfig;
use Ssch\TYPO3Rector\Set\Typo3LevelSetList;

return RectorConfig::configure()
    ->withPaths([__DIR__ . '/packages/my_extension/Classes'])
    ->withSets([
        Typo3LevelSetList::UP_TO_TYPO3_14,
    ]);

# Dry run first
ddev exec vendor/bin/rector process --dry-run

# Apply changes
ddev exec vendor/bin/rector process

# Review changes
git diff

ddev composer require "typo3/cms-core:^14.0" --no-update
ddev composer update
ddev typo3 cache:flush
ddev exec vendor/bin/phpunit

git add -A
git commit -m "feat: Apply Rector migrations for TYPO3 v14"

# Clear Rector cache
rm -rf .rector_cache/

# Run with verbose output
ddev exec vendor/bin/rector process --dry-run -vvv

ddev composer outdated
ddev composer show -l

# Core CLI: extension setup / schema alignment
ddev typo3 extension:setup --extension=my_extension

# `database:updateschema` is provided by helhum/typo3-console, not plain Core — only if installed:
#   ddev typo3 list | rg database
# ddev typo3 database:updateschema --verbose

<?php
// ❌ Old (deprecated)
GeneralUtility::getIndpEnv('TYPO3_REQUEST_HOST');

// ✅ New (TYPO3 v14)
$request = $GLOBALS['TYPO3_REQUEST'];
$normalizedParams = $request->getAttribute('normalizedParams');
$host = $normalizedParams->getRequestHost();

<?php
// ❌ Old (removed in TYPO3 v14 migration path)
$objectManager = GeneralUtility::makeInstance(ObjectManager::class);
$service = $objectManager->get(MyService::class);

// ✅ New (Dependency Injection)
public function __construct(
    private readonly MyService $myService,
) {}