I'd call that a continuous rewrite, which is also the strategy that worked best for me. If you're not willing to make these investments as you go, you may well

I'd call that a continuous rewrite, which is also the strategy that worked best for me. If you're not willing to make these investments as you go, you may well end up in a full-rewrite-or-die situation, I suppose. Comes down to how aggressively management prioritises short term results. I personally have never worked on a code base that far gone, but I can imagine they're out there.