To install a specific version of a Atatus PHP agent, you can follow the below steps.

Using package managers

On Debian-based systems (such as Ubuntu or Debian), you can refer here.

On Red Hat-based systems (such as Fedora or CentOS), you can refer here.

Using tarball

When installing agent from a tarball (a .tar.gz archive file), the version number is included in the file name. For example, the agent file name will look like atatus-php-1.17.0-x64-debian.tar.gz.

If you want to install a different version of the agent, you'll need to download the appropriate tarball file with the desired version number in the file name. Then, you can extract the contents of the tarball and follow the installation steps from here

Lets say you want to install 1.15.2, then tar ball for the Debian is atatus-php-1.15.2-x64-debian.tar.gz

You can see the list of PHP agent versions in the release notes.