On Full Stack Development: I consider myself a “Full Stack Developer” because I’ve had a great deal of front-end, middle-ware and back-end experience, but that doesn’t mean I’m proficient at all layers of the stack. I prefer C# over CSS. This quote restates is nicely: “Full-stack development is about exposing yourself to a broad range of ideas.”
Using a rules engine for a generic problem kinda looks and feels like a universal hammer that turns any problem unto a nail. One has to wonder, is a rules engine the best solution for a generic problem, or does the problem need to be redefined?
Whenever you approach a new legacy code base, the first thing you should do is get a high level overview of all the dependencies in that project. This lets you know what parts you need to refactor first and which ones need the most attention. Check Source Monitor, a free static analyzer.