Right, I didn't word that part very well indeed. You still have to retain the original license in any case but it only covers that particular bit of code. Any p

Right, I didn't word that part very well indeed. You still have to retain the original license in any case but it only covers that particular bit of code. Any product you create built on a MIT component can be licensed as you pleased. It depends what was meant by derivative and how this impacts the original code (encapsulated, modified, etc...). I was thinking more of when you use an MIT-licensed lib or 3rd party tool, or when you would reuse a code-snippet licensed as MIT and modify it. License and attributions remain, but only for that part of the code.