In theory yes, you're supposed to migrate away from the legacy codebase. In practice I've never, ever, ever seen that happen: it's too much upfront cost to sta

In theory yes, you're supposed to migrate away from the legacy codebase. In practice I've never, ever, ever seen that happen: it's too much upfront cost to start over, especially when you have real customers and real data on top of it and you need to keep pumping out new features.