Depending on your time zone, PHP 7 was finally released on 3rd/4th of December 2015. Even though the general recommendation for production servers is to wait for a little bit and gather some experiences before upgrading, some of us want to jump right on and upgrade to PHP 7.
In your WordPress site, there are directories that include PHP files that visitors should never be able to access directly. They are only there for WordPress to function as an application that runs on your server. But because of WordPress’ directory and file structure, they are kind of accessible to the public. All of them are meant to be part of a larger application – WordPress, that is – and should not cause any harm if called directly – that we know. Some of the files execute some code even when ran standalone. An attacker might know of a clever way to make that code run in an unexpected manner, causing harm. To be on the safe side, we should deny access to all these PHP files from the outside world. Since we block access to them in our Nginx configuration, PHP will still run them as usual and WordPress will work just fine.
WordPress requires write access to one directory, and that one directory only: the directory returned by wp_upload_dir(). By default, this is /wp-content/upload, but it can be configured to anything that is beneath your document root, like /media, if you want to.
As I’m writing this, the calendar shows April 14 2015. According to the PHP 7.0 timeline, it has a projected release date of November 2015. But if you want to try it out (to check out the speed), you can already do so.
HHVM can really speed up your PHP-based web site. Most reports are somewhere in the range of 2–4x faster. Unfortunately, HHVM isn’t very stable and will suddenly die, just of the blue, from time to another. Fortunately, if you’re running Nginx it’s really easy to set up PHP-FPM as a fallback.
Since version 3.9, WordPress have been 100% compatible with HHVM and I have begun replacing PHP with it on a few of my servers to experiment.
I always run the latest LTS version of Ubuntu on all my servers. Currently the latest LTS is 14.04 which comes with PHP version 5.5, but as of November 2014, the latest stable version is 5.6. So how do you get an updated, current version of PHP without resorting to having to maintain the packages yourself? The answer is in PPA.