A suite of dummy routines, compiled, tested, and deployed (to PyPI as wheels) for the whole build matrix: {Pythons 2.7, 3.4, 3.5, 3.6, 3.7} × {Windows 32-bit, Windows 64-bit, MacOS, manylinux1_i686, manylinux1_x86_64, manylinux2010_x86_64} × tested for {Numpy 1.13.1 or 1.14.5 (earliest available for a Python version) and latest}.
Eventually, Numba versions will be tested, though not as a whole matrix (earliest Numba with earliest Numpy, latest Numba with latest Numpy), so that adding Numba doesn't explode the size of the matrix.