This is the explicit plan already. I've recently merged #894 that goes in this direction, further pull requests that drop usages of defines are highly appreciated. Since P/Invoke is not a good fit for this approach, though (since the Mono method of using __Internal as the library name and pre-loading the library directly before use is not universally supported), we are looking into switching to delegates instead, see https://mail.python.org/pipermail/pythondotnet/2019-July/002067.html.

@lostmsu looked into this before, but wanted to implement some simple benchmarking to see how much this would regress performance.

To find out which Python version to use at runtime I'd like to make the version and library path explicit parameters to the Runtime.Initialize function.

Sounds great! I was not aware that it was explicitly planned.

The P/Invoke stuff would have to go, but I cannot imaging there would be any significant performance penalty using delegate, Marshal.GetDelegateForFunctionPointer and friends.

In any case having a benchmark would be good. Also enables profiling performance issues that might already be in the interface between CLR and Python.

@rmadsen-ks https://www.nuget.org/packages/Python.Runtime.UnofficialNetStandard/ currently does that. We are planning to upstream the necessary changes.

@lostmsu sounds great! Any way I can download the source?

@rmadsen-ks it is in this one: https://github.com/losttech/pythonnet , branch losttech/master . It is diverged a bit though.

@lostmsu, thanks, will check it out.

@lostmsu, I'm having trouble building the branch you linked. I'm working on a project with similar requirements as @rmadsen-ks. Are there any updates about the effort to remove compilation symbols from the build?

This have now been implemented in Python.NET 3.0 (preview available in master and on NuGet). One needs to set Runtime.PythonDLL before doing any other calls though, otherwise might get TypeInitializationException