5.0 Upgrade Guide

First, check that your application is running on latest CakePHP 4.x version.

Fix Deprecation Warnings

Once your application is running on latest CakePHP 4.x, enable deprecation warnings in config/app.php:

'Error' => [
    'errorLevel' => E_ALL,

Now that you can see all the warnings, make sure these are fixed before proceeding with the upgrade.

Some potentially impactful deprecations you should make sure you have addressed are:

  • Table::query() was deprecated in 4.5.0. Use selectQuery(), updateQuery(), insertQuery() and deleteQuery() instead.

Upgrade to PHP 8.1

If you are not running on PHP 8.1 or higher, you will need to upgrade PHP before updating CakePHP.


CakePHP 5.0 requires a minimum of PHP 8.1.

Use the Upgrade Tool


The upgrade tool only works on applications running on latest CakePHP 4.x. You cannot run the upgrade tool after updating to CakePHP 5.0.

Because CakePHP 5 leverages union types and mixed, there are many backwards incompatible changes concerning method signatures and file renames. To help expedite fixing these tedious changes there is an upgrade CLI tool:

# Install the upgrade tool
git clone https://github.com/cakephp/upgrade
cd upgrade
git checkout 5.x
composer install --no-dev

With the upgrade tool installed you can now run it on your application or plugin:

bin/cake upgrade rector --rules cakephp50 <path/to/app/src>
bin/cake upgrade rector --rules chronos3 <path/to/app/src>

Update CakePHP Dependency

After applying rector refactorings you need to upgrade CakePHP, its plugins, PHPUnit and maybe other dependencies in your composer.json. This process heavily depends on your application so we recommend you compare your composer.json with what is present in cakephp/app.

After the version strings are adjusted in your composer.json execute composer update -W and check its output.

Update app files based upon latest app template

Next, ensure the rest of your application has been updated to be based upon the latest version of cakephp/app.