# Typo3 Simplify

> Simplify and refine TYPO3 extension code for clarity, consistency, and maintainability while preserving functionality. Reviews PHP classes, Fluid templates, TCA, Services.yaml, and ext_localconf/ext_tables for TYPO3 v14 best practices. Run after implementing a feature or before merging a PR. Use when working with simplify, clean up, refine, code quality, reduce complexity, readability, maintainability, review code, polish, TYPO3 code review.

- Skill: `dirnbauer/typo3-simplify` (Agent Skill)
- Install (CLI): `npx skillmds@latest add dirnbauer/typo3-simplify`
- Raw SKILL.md: https://api.skillmd.com/api/skills/dirnbauer/typo3-simplify/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- License: Apache-2.0 OR CC-BY-SA-4.0
- Author: dirnbauer (https://skillmd.com/u/dirnbauer)
- Updated: 2026-09-10
- Page: https://skillmd.com/skills/dirnbauer/typo3-simplify

---


# TYPO3 Code Simplifier

> Adapted from Boris Cherny's (Anthropic) code-simplifier agent for TYPO3 contexts.
> **Target:** TYPO3 v14.x only.

Simplify and refine recently changed TYPO3 code. Preserve all functionality. Focus on
clarity over cleverness, TYPO3 API usage over custom implementations, and v14 patterns
over deprecated approaches.

## Process

1. Identify recently modified files (use `git diff --name-only HEAD~1` or staged changes)
2. Run three parallel review passes: **Reuse**, **Quality**, **Efficiency**
3. Aggregate findings, deduplicate, sort by impact
4. Apply fixes, verify no behavior change

## Pass 1: TYPO3 API Reuse

Find custom implementations that duplicate what TYPO3 already provides.

### Replace Custom Code with Core APIs

| Custom Pattern | TYPO3 API Replacement |
|---|---|
| Manual DB queries (`$connection->executeQuery(...)`) | `QueryBuilder` with named parameters |
| `$GLOBALS['TYPO3_REQUEST']` | Inject `ServerRequestInterface` via middleware/controller |
| `new FlashMessage(...)` + manual queue | `FlashMessageService` via DI |
| Manual JSON response construction | `JsonResponse` from PSR-7 |
| `GeneralUtility::makeInstance()` | Constructor injection via `Services.yaml` |
| `$GLOBALS['TSFE']->id` | `$request->getAttribute('frontend.page.information')?->getId()` (canonical on v14; `routing` page id also works) |
| `$GLOBALS['BE_USER']` | Inject `Context` or `BackendUserAuthentication` |
| `ObjectManager::get()` | Constructor DI |
| Manual file path resolution | `PathUtility`, `Environment::getPublicPath()` |
| Custom caching with globals | `CacheManager` via DI with cache configuration |
| `BackendUtility::getRecord()` for single field | `QueryBuilder` selecting only needed columns |
| Manual page tree traversal | `RootlineUtility` or `PageRepository` |
| `GeneralUtility::_GP()` / `_POST()` / `_GET()` | `$request->getQueryParams()` / `getParsedBody()` |
| `$GLOBALS['TYPO3_CONF_VARS']['EXTCONF']` writes | PSR-14 events or `ExtensionConfiguration` |
| Manual link generation | `UriBuilder` (backend) or `ContentObjectRenderer::typoLink()` |

### Replace Deprecated Patterns (v14)

| Deprecated | v14 Replacement |
|---|---|
| `ext_localconf.php` hook arrays | `#[AsEventListener]` on PSR-14 events |
| `$GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']` hooks | PSR-14 events |
| `ext_tables.php` module registration | `Configuration/Backend/Modules.php` |
| `XCLASS` | PSR-14 events or DI decoration |
| TCA `eval` for `required`, `null` | Dedicated TCA keys: `required`, `nullable` |
| TCA `eval` for `trim` | Still valid in v14 — no dedicated TCA replacement; keep `trim` in `eval` when you need it |
| `renderType => 'inputDateTime'` | `'type' => 'datetime'` |
| `'type' => 'input', 'eval' => 'int'` | `'type' => 'number'` |
| `items` with numeric array keys | `items` with `label`/`value` keys |

### Historical removals (pre–v14 code you may still read)

| Removed / legacy | When | Modern approach |
|---|---|---|
| `switchableControllerActions` | Deprecated in **v10.3** ([#89463](https://docs.typo3.org/c/typo3/cms-core/main/en-us/Changelog/10.3/Deprecation-89463-SwitchableControllerActions.html)), removed in **v12.0** | Separate plugin registrations |
| Signal/Slot `Dispatcher` | Removed in **v12** | PSR-14 events |
| `AbstractPlugin` (pi_base) | Made `@internal` **v12.0** (#98281), deprecated **v12.4** (#100639), removed **v13.0** | Extbase or middleware |

### Code quality (not deprecations)

| Topic | Guidance |
|---|---|
| `$querySettings->setRespectStoragePage(false)` | Valid Extbase API — prefer setting **query settings in the repository factory or controller**, not scattered in repositories, for clarity |

## Pass 2: Code Quality

### PHP Classes

- [ ] One class per file, PSR-4 autoloading
- [ ] `declare(strict_types=1)` on every PHP file
- [ ] `final` on classes not designed for inheritance
- [ ] `readonly` on immutable properties
- [ ] Constructor promotion for DI dependencies
- [ ] Explicit return types on all methods
- [ ] No unused `use` imports
- [ ] No suppressed errors (`@`)
- [ ] Guard clauses over deep nesting (early returns)
- [ ] No mixed types where specific types exist
- [ ] Replace `array` typehints with typed arrays or DTOs

```php
// Before
class MyService
{
    private ConnectionPool $connectionPool;
    private Context $context;

    public function __construct(ConnectionPool $connectionPool, Context $context)
    {
        $this->connectionPool = $connectionPool;
        $this->context = $context;
    }

    public function getData($id)
    {
        // ...
    }
}

// After
final class MyService
{
    public function __construct(
        private readonly ConnectionPool $connectionPool,
        private readonly Context $context,
    ) {}

    public function getData(int $id): array
    {
        // ...
    }
}
```

### Fluid Templates

- [ ] No inline PHP or complex ViewHelper chains
- [ ] Use `<f:translate>` instead of hardcoded strings
- [ ] Use `<f:link.page>` / `<f:link.typolink>` instead of manual `<a href>`
- [ ] Use `<f:image>` instead of manual `<img>` tags
- [ ] Partials for repeated markup (DRY)
- [ ] Sections for layout slots, not for reuse (use Partials)
- [ ] No `{variable -> f:format.raw()}` unless absolutely necessary (XSS risk)
- [ ] Variables use camelCase
- [ ] Remove empty `<f:section>` blocks
- [ ] Simplify nested `<f:if>` to `<f:switch>` or ternary where clearer

### TCA

- [ ] Use v14 `items` format with `label`/`value` keys
- [ ] Remove redundant `'exclude' => true` on fields already restricted
- [ ] Use dedicated types: `'type' => 'email'`, `'type' => 'datetime'`, `'type' => 'number'`, `'type' => 'link'`, `'type' => 'color'`, `'type' => 'json'`
- [ ] Use `'required' => true` instead of `'eval' => 'required'`
- [ ] Use `'nullable' => true` instead of `'eval' => 'null'`
- [ ] `eval` => `trim` remains supported — do not remove unless you replace trimming in another layer
- [ ] Remove `'default' => ''` on string fields (already default)
- [ ] Consolidate palette definitions (remove single-field palettes)
- [ ] Remove boilerplate `columns` definitions auto-created from `ctrl` on TYPO3 v14: `hidden`, `starttime`, `endtime`, `fe_group`, `sys_language_uid`, `l10n_parent`, `l10n_diffsource`
- [ ] Use palettes for enablecolumns: Core uses palette key **`hidden`** for `hidden`, **`access`** for `starttime`, `endtime`, `fe_group` (verify keys in your table’s `types` `showitem`)
- [ ] Remove **standard ctrl columns** from `ext_tables.sql` when `ctrl` enables them (`hidden`, `starttime`, `endtime`, `fe_group`, `sys_language_uid`, `l10n_parent`, `l10n_source`, `sorting`, `deleted`, `crdate`, `tstamp`) — only if they are auto-managed for that table
- [ ] Remove unused `showitem` fields from types

### Services.yaml

- [ ] Use autowiring (remove explicit argument definitions when type-hintable)
- [ ] Use `_defaults: autowire: true, autoconfigure: true, public: false`
- [ ] Remove manual service definitions for classes that autowiring handles
- [ ] Remove `factory:` blocks when autowiring handles construction; keep `factory:` for non-trivial construction that autowiring cannot resolve. `#[Autoconfigure]` tags/configures services but does **not** replace `factory:` construction
- [ ] Remove `public: true` unless needed for `GeneralUtility::makeInstance()`

### ext_localconf.php / ext_tables.php

- [ ] Minimize code — move to `Configuration/` files where possible
- [ ] Plugin registration only (no business logic)
- [ ] Frontend plugins: `ExtensionUtility::configurePlugin()` in `ext_localconf.php` **and** `ExtensionUtility::registerPlugin()` (or TCA `items`) in `Configuration/TCA/Overrides/tt_content.php` — both are required for a complete registration
- [ ] No `addPageTSConfig` — use `Configuration/page.tsconfig`
- [ ] No `addUserTSConfig` — use `Configuration/user.tsconfig`
- [ ] No `addTypoScript` — use `Configuration/TypoScript/setup.typoscript`

## Pass 3: Efficiency

- [ ] QueryBuilder: select only needed columns, not `*`
- [ ] QueryBuilder: add `setMaxResults()` when expecting single row
- [ ] Use `count()` queries instead of fetching all rows to count
- [ ] Cache expensive operations with TYPO3 Caching Framework
- [ ] Avoid N+1 queries in Extbase repositories (use `JOIN` or batch loading)
- [ ] Use `TYPO3\CMS\Core\Resource\ProcessedFileRepository` not re-processing on every request
- [ ] Remove `findAll()` calls without pagination
- [ ] Lazy-load file references with `#[\TYPO3\CMS\Extbase\Attribute\ORM\Lazy]` (replace legacy `@Lazy` annotation)
- [ ] Replace `foreach` + manual `in_array()` filtering with QueryBuilder `WHERE IN`
- [ ] Remove redundant `cache:flush` calls in CLI commands

## Output Format

After analysis, report findings grouped by file:

```text
## Classes/Controller/MyController.php

:42 — replace GeneralUtility::makeInstance(MyService::class) → constructor injection
:18 — add return type `: ResponseInterface`
:55 — deprecated: $GLOBALS['TSFE']->id → $request routing attribute
:67 — guard clause: invert condition, return early, reduce nesting

## Resources/Private/Templates/List.html

:12 — hardcoded string "No items found" → f:translate
:34 — manual <a href> → f:link.page

## Configuration/TCA/Overrides/tt_content.php

:8 — legacy items format `['Label', 'value']` → `['label' => 'Label', 'value' => 'value']`

Applied 7 fixes. No behavior changes. Run tests to verify.
```

## Version fallbacks

When the **same codebase** must run on **TYPO3 v13 and v14** (dual-version extensions), you may temporarily keep transitional patterns:
- Register PSR-15 middleware in `Configuration/RequestMiddlewares.php` (Core-supported pattern)
- Keep `Services.yaml` event listener config alongside `#[AsEventListener]`
- Keep numeric TCA `items` arrays alongside `label`/`value` format
- Prefer `Services.yaml` `_defaults` (`autowire` / `autoconfigure`) plus Core registration attributes (`#[AsCommand]`, `#[AsEventListener]`, …) over ad-hoc `factory:` blocks

## v14-Only Simplification Targets

> The following simplification opportunities are **v14-specific**.

### v14 Simplification Patterns **[v14 only]**

| Pattern | Simplification |
|---------|---------------|
| `$GLOBALS['TSFE']` access | **Fatal error in v14** (Breaking #107831) — replace with `$request->getAttribute('frontend.page.information')` |
| Extbase annotations (`@validate`) | Replace with `#[\TYPO3\CMS\Extbase\Attribute\Validate]` |
| `MailMessage->send()` | Inject `TYPO3\CMS\Core\Mail\MailerInterface` and call `$this->mailer->send($email)` |
| `FlexFormService` usage | Prefer `FlexFormTools`; `FlexFormService` remains as a BC alias in v14 but should not be used in new code |
| Bootstrap Modal JS | **Frontend:** native `<dialog>` where appropriate. **Backend:** use `@typo3/backend/modal` — it wraps **native `<dialog>`** in v14 (Breaking #107443); do not use raw Bootstrap modal JS |
| TCA `ctrl.searchFields` (removed in v14) | TYPO3 v14 derives backend search fields automatically; tune inclusion per column with `'searchable' => true/false` (supported field types: `input`, `text`, `email`, `link`, `slug`, `color`, `datetime` (without custom `dbType`), `flex`, `json`, `uuid`) where supported |
| Custom localization parsers | Superseded by Symfony Translation Component integration ([Feature #107436](https://docs.typo3.org/c/typo3/cms-core/main/en-us/Changelog/14.0/Feature-107436-SymfonyTranslationIntegration.html)); BC maintained in v14 — prefer the new Symfony Translation API in new code |
| `GeneralUtility::createVersionNumberedFilename()` | Replace with `SystemResourceFactory` / `SystemResourcePublisherInterface` (System Resource API, [Feature #107537](https://docs.typo3.org/c/typo3/cms-core/main/en-us/Changelog/14.0/Feature-107537-SystemResourceAPIForSystemFileAccessAndPublicUriGeneration.html)) |

---

## Credits & Attribution

This skill is based on the excellent work by
**[Anthropic](https://github.com/anthropics/claude-plugins-official/tree/main/plugins/code-simplifier)**.

Original repository: https://github.com/anthropics/claude-plugins-official/tree/main/plugins/code-simplifier

Special thanks to [Anthropic](https://github.com/anthropics/claude-plugins-official/tree/main/plugins/code-simplifier) for their generous open-source contributions, which helped shape this skill collection.
Adapted by webconsulting.at for this skill collection