pjenvey

3.6's order-preserving dict was first implemented by PyPy (so it's already had it for years, even in pypy2) and f-strings were back ported to pypy3 too.

Come by the PyPy IRC channel and ask

pypy3 has always supported the u'' prefix despite it otherwise being limited to 3.2 support.

Since this is pure Python performance you might want to give the different algorithms a try on PyPy

All of the stackless/continuation related features included in Python 2 pypy should be supported on PyPy3 or it's a bug.

Implementing Python 3.3's yield from in RPython should actually be fairly easy. One of the PyPy GSoC students may get around to doing it this summer

Use SQLAlchemy.

Not via ctypes, via CPyExt, a layer emulating the CPython C extension API (it actually implements a reference counting GC and everything)