Melee

Super Smash Bros. Melee is a 2001 platform fighter game developed by HAL Laboratory and published by Nintendo.

Slippi

You can use the slippi-nixflake to declaratively install and configure Slippi with Nix, or get the AppImage directly from Slippi's website.

B0XX Emulation

B0XX controller emulation can be done via keyb0xx.A Nix package for keyb0xx can be found here.