The patcher for Rocket Slime 3DS - based off of DGS's implementation. This is a standalone build of GodMode9 which boots straight to \data\autorun.gm9.
Build RS3DS-Patcher.firm via make FLAVOR=RS3DS-Patcher SCRIPT_RUNNER=1 FIXED_BRIGHTNESS=15.
This requires firmtool, Python 3.5+ and devkitARM installed.