Every time I’ve installed a new installation of WordPress, I would install the latest version. Naturally. And 99% of the time, why wouldn’t you?

Today, however, I explicitly needed to test a release against an older version of WordPress Core. In doing so, I learned a couple of useful things.

1. WP CLI Version Flag

This is more of a side-note but you can pass a --version flag to the wp core download sub-command in WP CLI to specify a version. I kind of assumed this was possible when going into the task but, having never needed this before, it was nice to confirm it was there. If you need to download WordPress Core at version 5.9, for example, you can run the following command in your Terminal application:

wp core download --version=5.9

Check out the docs for a full list of options.

Of course, it isn’t super useful when you download a specific version only to have it automatically updated when you get to the installation step. But I’ll cover that in the next section – which is the main purpose of this post!

2. Core Auto-Updates

As of WordPress version 5.6, new installations will auto-update to the latest version by default. I happened to have been trying to install version 5.9.5. After being tripped up by a couple attempts that resulted in the automatic version bump during the install, I realized what was going on and dug in a bit more.

Fortunately, there is a handy constant to disable this behavior:

In your wp-config.php file, right before the “stop editing” line, set the following before running the installation:

define( 'WP_AUTO_UPDATE_CORE', false );

With this in place, you can safely run the installation without worrying about Core updating to the latest version.

Again, there probably aren’t too many scenarios where you wouldn’t want to install the latest version (for a variety of reasons). However, this is useful if you’re building something and need to test backward-compatibility!