Programmer Skyfloogle, has released Red Viper, an updated virtual-boy emulator for the 3DS.
GitHub - skyfloogle/red-viper: A Virtual Boy emulator for the 3DS
https://github.com/skyfloogle/red-viper
A Virtual Boy emulator for the 3DS. Contribute to skyfloogle/red-viper development by creating an account on GitHub.
From the github description: "A Virtual Boy emulator for the Nintendo 3DS continuing mrdanielps's work on r3Ddragon, which is itself based on Reality Boy / Red Dragon. It uses a dynamic recompiler with busywait detection and a hardware-accelerated renderer to achieve high performance on the 3DS's limited hardware."