CoreRT is the native runtime for the compilation of .NET natively ahead of time and it is a part of the new .NET Native (as announced in April 2014).
It is not a virtual machine and it does not have the facility of generating and running the code on the FLY as it doesn’t INCLUDE a JIT. It has the ability for RTTI(run-time type identification) and reflection, along with that it has GC(Garbage Collector).
The type system of the CoreRT is designed in such a way that metadata for reflection is not at all required. This feature enables to have an AOT toolchain that can link AWAY unused metadata and can identify unused APPLICATION code.