JSMESS Achieves a Hero’s Death

If you just want something to manage your game library, you can use my project, Start9.io (http://start9.io). We currently support GB, GBC & GBA games, and I plan to add SNES support as soon as I can spare some time.

As for the emularity project, I can only advise you to use my Virtjs devices* in order to give modularity to your users at virtually no cost.

The Emscripten SDL implementation is nice, but not easy enough to interact with when it comes to an actual project rather than a proof of concept. Good luck!

* https://github.com/arcanis/virtjs