http://docs.overviewer.org/en/latest/building/#id4
# Building with mingw-w64 and msys2


# commands
pacman -S git mingw-w64-x86_64-python3-numpy mingw-w64-x86_64-python3-Pillow mingw-w64-x86_64-python3 mingw-w64-x86_64-toolchain
git clone https://github.com/overviewer/Minecraft-Overviewer.git
cd Minecraft-Overviewer
python3 setup.py build


# build output
C:\msys64\mingw64\bin/x86_64-w64-mingw32-gcc.exe -Wno-unused-result -Wsign-compare -DNDEBUG -march=x86-64 -mtune=generic -O2 -pipe -fwrapv -D__USE_MINGW_ANSI_STDIO=1 -D_WIN32_WINNT=0x0601 -DNDEBUG -march=x86-64 -mtune=generic -O2 -pipe -fwrapv -D__USE_MINGW_ANSI_STDIO=1 -D_WIN32_WINNT=0x0601 -DNDEBUG -I. -IC:/msys64/mingw64/lib/python3.8/site-packages/numpy/core/include -IC:/msys64/mingw64/include/python3.8 -c overviewer_core/src/main.c -o build/temp.mingw-3.8/overviewer_core/src/main.o
In file included from overviewer_core/src/main.c:18:
overviewer_core/src/overviewer.h:40:10: fatal error: Imaging.h: No such file or directory
   40 | #include <Imaging.h>
      |          ^~~~~~~~~~~
compilation terminated.
Traceback (most recent call last):
  File "C:/msys64/mingw64/lib/python3.8/distutils/cygwinccompiler.py", line 192, in _compile
    self.spawn(self.compiler_so + cc_args + [src, '-o', obj] +
distutils.errors.DistutilsExecError: command 'C:\\msys64\\mingw64\\bin/x86_64-w64-mingw32-gcc.exe' failed with exit status 1


# fixed by copying the headers into the toplevel dir and running python3 setup.py build again
cp -pv /c/msys64/mingw64/include/python3.8m/Imaging.h .
cp -pv /c/msys64/mingw64/include/python3.8m/ImPlatform.h .
cp -pv /c/msys64/mingw64/include/python3.8m/ImagingUtils.h .