This is the Steve's Carts 2 mod for Minecraft - It has not been updated for a while.
Per the following tweet, anyone is free to clone this code, and create a version of the mod.
In possession of the source of my mc mods? You're allowed to distribute it, update it, tweak it and release it. Just credit me for my work.
— Vswe (@Steves_Carts) November 6, 2016
As this version of the mod is not currently under development, we recommend checking out some of the excellent community forks.