Multi-OS build with Appveyor and Travis CI

And it also allows C compiling to binary, as long as you can get the right setup.

I use this with Node better-sqlite3, where prebuilt binary for Windows is not working (with Electron), and I am running development on MacOS.

.travis.yml

appveyor.yml

This is also a possibility with Python PyInstaller / py2exe / py2app, and Golang with cgo.

Not yet sure about packaging Java...