Eints Is a Newgrf Translation Service. Though now it is also used for Game Scripts and OpenTTD itself.
Eints is written in Python 3.
You can find more details in docs/manual.
Eints software uses the GPL V2. For stand-alone use (which is useful for development and testing), no other software is needed.
Internally, it uses:
The Eints repository includes files of the above projects for your convenience. They are however not part of Eints.