Perhaps you could try python, numpy, twisted, inline callbacks and one of the python opencl packages.
Inline callbacks are syntactic sugar included recent versions of twisted that make your code look synchronous while still running on the event loop.
With python, you get to use a wealth of libraries, but you need to still be mindful of what is blocking.
Wnen something you need to call is blocking, you can try deferToThread.
Don't worry, you won't need to think too much about race conditions and other concurrency issues with threading since there is the GIL in python. Also, Twisted makes it a cinch.
Inline callbacks are syntactic sugar included recent versions of twisted that make your code look synchronous while still running on the event loop.
With python, you get to use a wealth of libraries, but you need to still be mindful of what is blocking.
Wnen something you need to call is blocking, you can try deferToThread.
Don't worry, you won't need to think too much about race conditions and other concurrency issues with threading since there is the GIL in python. Also, Twisted makes it a cinch.
Good luck!