Run emulators in Minecraft!
First, you need Forge for Minecraft 1.12.2. (Download the recommended version)
Then you need to put the .jar into your mods folder. After opening the game with the mod installed once, you will see a new folder in your minecraft folder called "roms". Go into "roms" and put your NES roms into the "nes" folder. After you restart the game, you will see the roms as cartridges in the "MCEmu: NES" creative category.
To build, run ./gradlew build in the root directory of the project.
To build, run gradlew.bat build using cmd in the root directory of the project.