This is LegacyReader, which is an app the displays music using logic (I need to implement it)!
Any contribution, beside a malicious one, is a good one. I will generally prefer multi-line changes, rather than small ones, but I'll take them anyway. I'll use your contributions to help with this project.
Head over to the projects page to see what you want to help out with.
Also, make sure to open an issue when you want something.
Find me at X (formerly Twitter) here.