Phidl
Phidl is a parametric design library implemented in Python, which allows you to code your designs. This can be particularly useful in designs, that are meant to be parametrically extended in some way. Even if this is not the case, after you build the design, it is particularly easy to manipulate parameters, without having to do it manually.
More information can be found by reading the documentation and on the official python site, where you can also find out how to cite the package.
Oliver Liebe's designs and tutorials are another source of information. In these you will find the full code for a quantum dot chip fully implemented in Phidl. The design is of course specific, but the code is built up in a general way, such that reusing it and altering it should be manageable.
A first tutorial is currently being written, and is up on the repository as well. It will be expanded in the near future.