[eesmith]

The thing is, I don't think I have an option to use anything other than setup.py. For example, I read:

> and as part of the deprecation of distutils, having setuptools installed at all even when you don't import it can change the behavior of import distutils.

How am I supposed to replace the following (a modified version of https://stackoverflow.com/questions/724664/python-distutils-... ):

  from setuptools import Extension, setup
  from distutils.command.build_ext import build_ext

  copt =  {'msvc': ['/openmp', '/Ox', '/fp:fast','/favor:INTEL64','/Og']  ,
     'mingw32' : ['-fopenmp','-O3','-ffast-math','-march=native']       }
  lopt =  {'mingw32' : ['-fopenmp'] }

  class build_ext_subclass( build_ext ):
      def build_extensions(self):
          c = self.compiler.compiler_type
          if copt.has_key(c):
             for e in self.extensions:
                 e.extra_compile_args = copt[ c ]
          if lopt.has_key(c):
              for e in self.extensions:
                  e.extra_link_args = lopt[ c ]
          build_ext.build_extensions(self)

If distutils is deprecated, and setuptools causes problems ... what should I do?

I know setuptools is a "hot mess". It took hours of puzzling to figure out how to compile things correctly, and includes input from other people who spent hours puzzling things out.

So I am ... sad isn't quite right. Depressed? Down? Feeling like and outsider? .. every time I am reminded that I am not one of the "most people" in "works for most people".

While I (and you) are here, is some way to distinguish between "developer" build environments and "deployment" build environments?

I was looking more at the general topic, trying to figure out how to migrate. I saw this example:

  [build-system]
  requires = ["setuptools >= 40.6.0", "wheel"]
  build-backend = "setuptools.build_meta"

I have two build environments. A development build environment requires Cython (I have hand-written Python/C extensions and Cython extensions). On the other hand, source distributions include the "cythonized" C code from Cython, so people who install and deploy from source don't need Cython. [1]

In my setup.py I say:

  try:
    from Cython.Build import cythonize
  except ImportError:
    def cythonize(x):
        return x
    def rename(filename):
        return filename.replace(".pyx", ".c")

  else:
    def rename(filename):
        return filename
   ...
     = cythonize([Extension("spam", sources = [rename("foo.pyx"), "bar.c"])])

Is there a way to distinguish these two environments in pyproject.toml?

[1] Other than 'setuptools' and the need for a C compiler, my package has no dependencies when building from a source distribution.

EDIT: P.S. A reason to stick with "python setup.py develop" instead of "pip install -e ." is to avoid that frequent nag to "consider upgrading" pip. ;)