Wow you copy an existing mod and upload it as yours without mentioning the original author.
You must be a really successful person /s

https://mods.factorio.com/mod/naked-rails

It's published under unlicense so you can't use simply MIT here.

I didn't even know that mod existed. I just made this in 10 minutes for my personal use because I didn't like the way vanilla rails looked against pavement, and I figured others may find it useful. The graphics in this mod (and the other too I presume) are generated simply by disabling one or two layers of the default ones.
If you actually looked more into the mod than just glancing over screenshots, you'd notice that the construction method is different than the one in Naked Rails, as well as a large portion of the code.
You're of course free to not use this mod.