> Not everything is a new cleanly constructed codebase. This is true, in lots of ways. Lots of code is rushed, corners cut, so was bad the moment it was writte

> Not everything is a new cleanly constructed codebase. This is true, in lots of ways. Lots of code is rushed, corners cut, so was bad the moment it was written. Other code is written in a particular style, and would need to be cleaned up to match a more modern style. One benefit of backwards compatibility within one language is that these pieces of code can be improved incrementally, without having to switch languages. So, a road to improvement, rather than a source of mistakes. The key is to make the new code better than the old code!