  Extensions to the C++ implementation of the QCD Data Parallel Interface are
provided enabling acceleration of expression evaluation on NVIDIA GPUs. Single
expressions are off-loaded to the device memory and execution domain leveraging
the Portable Expression Template Engine and using Just-in-Time compilation
techniques. Memory management is automated by a software implementation of a
cache controlling the GPU's memory. Interoperability with existing Krylov space
solvers is demonstrated and special attention is paid on 'Chroma readiness'.
Non-kernel routines in lattice QCD calculations typically not subject of
hand-tuned optimisations are accelerated which can reduce the effects otherwise
suffered from Amdahl's Law.
