To get SPLTypes like SplEnum on Uberspace you have to follow their Wiki and install the PECL module for it:
uberspace-install-pecl SPL_Types
You will then get the message:
Error: make failed - please contact hallo@uberspace.de for help! We have left the build directory /tmp/tmp.G0COZLlxLp in place.
You have to contact the team at hello@uberspace.de and they will install it for your manually.