Breaking: #98319 - New file location for LocalConfiguration.php and AdditionalConfiguration.php

See forge#98319


Every TYPO3 installation requires a mandatory file named typo3conf/LocalConfiguration.php.

This file contains system-wide configuration options such as database credentials, or paths to image processing details.

Historically, the very original name was typo3conf/localconf.php (this is also where the extension's file name ext_localconf.php comes from).

This file was renamed in TYPO3 v6.0 to LocalConfiguration.php and since then returns a PHP array with settings then available in $TYPO3_CONF_VARS.

Specific PHP code with additional logic (e.g. context-specific conditions) was available in typo3conf/AdditionalConfiguration.php.

With TYPO3 v12, the names for both files and their location have been changed.

The prefix "Local" in LocalConfiguration.php originates from the three-divided location of "System", "Global" and "Local" extensions - the latter is "specific to a TYPO3 installation" where as other extensions and configuration could be shared with multiple TYPO3 installations.

TYPO3 v12 has a strong support for Composer and TYPO3's own code base has progressed since 2012, when TYPO3 v6.0 was released. TYPO3 Core itself now only consists of extensions which are available as native Composer packages. The concept of global extensions has been phased out over the past versions.

Instead, TYPO3 installations now distinguish between "dependencies" such as custom extensions, TYPO3 Core extensions or extensions from or TYPO3 Extension Repository, and "project-specific" configuration. This project-specific configuration - as known from other PHP frameworks - is now placed in a settings configuration file and additional configuration file.

Newcomers or users from other PHP projects might understand the concept of a file with certain settings much better, so the file locations and the file names have been changed.

For non-Composer-based installations the file names are:

  • typo3conf/LocalConfiguration.php is now available in typo3conf/system/settings.php
  • typo3conf/AdditionalConfiguration.php is now available in typo3conf/system/additional.php

Composer-based TYPO3 projects by default have the possibility to place certain files from outside the document root, and using the document root such as public/ as a subfolder. This way, Composer-based TYPO3 projects can restrict direct public access to such files via the webserver.

TYPO3 in its Composer Mode already creates a folder named config/ on the project root level, where e.g. site configuration is stored. Within the config/ folder, the new location is placed.

  • typo3conf/LocalConfiguration.php is now available in config/system/settings.php
  • typo3conf/AdditionalConfiguration.php is now available in config/system/additional.php


TYPO3 automatically moves typo3conf/LocalConfiguration.php and typo3conf/AdditionalConfiguration.php to their respective new places on the first PHP request. The old file is not evaluated anymore, as soon as the file in the new location is available.

Affected installations

All TYPO3 installations prior to TYPO3 v12.


The configuration files are automatically moved with TYPO3 v12.0 to their new locations, so no manual process is needed.

Projects working with a version control system such as Git might need to adapt their .gitignore file or their deployment strategies.

In addition, TYPO3 projects relying on the file locations and their structures might need adaptions.