It would be good if we can make Gini compatible with Python3, since support for version 2 will be dropped soon. Also, since the structure is quite complicated, we should improve the quality in terms of code commenting, modularization, following style guides, etc.

• Modularize the software: This is related to Generalize the router interface in GINI #40 and Generalize the machine #41. One idea is provide abstract classes for each network component so that it's easier to add different concrete implementation.
• Add code commenting: This helps us understand how the GUI components interact and how front-end - back-end communicate. This makes debugging and improving routing/compiling algorithm possible.
• Follow style guides: https://www.python.org/dev/peps/pep-0008/
• Add tests and travis integration: There used to be TravisCI for Gini3: https://github.com/anrl/gini3. We can adapt from the old test suite and add more cases