SumatraPDF is a multi-format (PDF, EPUB, MOBI, FB2, CHM, XPS, DjVu) reader for Windows under (A)GPLv3 license, with some code under BSD license (see AUTHORS).
To compile you need Visual Studio 2017. Free Community edition works. I tend to update to the latest release of Visual Studio. Lately C++ evolves quickly and Visual Studio constantly adds latest capabilities. If things don't compile, first make sure you're using the latest update of Visual Studio.
To get the code:
git clone firstname.lastname@example.org:sumatrapdfreader/sumatrapdf.git
vs2017/SumatraPDF.sln when using Visual Studio 2017