Most of the time it’s better to adapt existing code than light a match and start again. For example, I’ve seen and participated in the transition of a complete

Most of the time it’s better to adapt existing code than light a match and start again. For example, I’ve seen and participated in the transition of a completely undocumented custom web framework (with an entirely Redis based ORM) to an industry standard web framework with a MySQL backed ORM. All of this happened without any customers noticing, no feature development pause, no huge “rewrite” branch requiring regular rebasing, and without the original development team responsible for the mess. That was truly a work of art.