The appserver.io runtime environment is delivered by the package runtime. This package provides a runtime that is system independent and encloses a thread-safe compiled PHP environment. Besides, the most recent PHP 5.5.x version the package comes with follows installed extensions:
Additionally, the PECL extensions XDebug and ev
are compiled as shared modules.
XDebug is necessary to render detailed code coverage reports when
running unit and integration tests.
ev will be used to integrate a timer service in one of the future