If you're looking for help fixing the mess you are dealing with, find the book Working Effectively with Legacy Code - https://www.amazon.com/Working-Effectively

If you're looking for help fixing the mess you are dealing with, find the book Working Effectively with Legacy Code - https://www.amazon.com/Working-Effectively-Legacy-Michael-Feathers/dp/0131177052/ref=sr_1_1?dchild=1&keywords=working+with+legacy+code&qid=1600701564&s=books&sr=1-1 https://www.amazon.com/Working-Effectively-Legacy-Michael-Fe.... You might also want to read Refactoring to Patterns, but the legacy book is more important to start with.