Packages of PHP 5.5 are available in my repository. Note that these are debug builds and might require the use of the [testing] repository.
[php] Server = https://repo.pierre-schmitz.com/$repo/os/$arch
Only try this at home. APC gets replaced by APCu for user data caching. Use the new opcache module to cache the PHP scripts. XCache is also available as a development snapshot.
Let me know of any issues but also successes. More will follow up soon.