Support

This is not possible in WordPress. Since you come from Joomla, let me explain why – some of that information you might already know.

WordPress' Roles are equivalent to Joomla's User Groups. Likewise, WordPress' Capabilities are equivalent to Joomla's Permissions.

While WordPress does allow a plugin to define custom capabilities, there is no provision in the WordPress core to manage Roles and which Capabilities each Role provides. As a result, there is no way for the site's owner to manage which group can do what for each plugin.

For this reason, the mapping of roles to Akeeba Backup's internal permissions is hard-coded in the wp-content/plugins/akeebabackupwp/helpers/Solo/Application/WordPressUserPrivileges.php file. In there, you will see that we are only allowing Administrators (single site installations) or the Super Administrator (multi-site installations) to access Akeeba Backup and take any action. This is intentional; even taking a backup can be a security-sensitive action, e.g. a malicious author could run backups continuously to waste CPU and disk resources.

Can you please explain your use case to me? I am not happy with our current approach, but doing anything different requires having a good understanding of how people intend to use whatever new system we create. Explaining your use case to me will help a lot.