Libretro is a simple but powerful development interface that allows for
the easy creation of emulators, games and multimedia applications that
can plug straight into any libretro-compatible frontend. This development
interface is open to others so that they can run these pluggable emulator
and game cores also in their own programs or devices.

Snes9x is an emulator for the Super Nintendo Entertainment System / Super
Famicom.  This package is derived from the master repository of Snes9x. It
has greater accuracy and worse performance than Snes9x 2005/2010. It has
a less strict approach to accuracy than bsnes and therefore doesn't run
problematic games like bsnes, but has much better performance.

This is the most up-to-date libretro snes9x core available, and is
recommended for netplay.

Homepage:
https://docs.libretro.com/library/snes9x/
