How you migrate is everything

Production systems are perpetually mid-migration as requirements, best practices, and teams evolve. Good software barely works for its current purpose, and engineering is about adapting systems over time rather than achieving perfection. Successful migrations require incremental changes that keep software functional, visible wins to maintain buy-in, team collaboration, and supporting old and new systems in parallel. The hardest challenges involve building new abstractions and managing data migrations while maintaining backward compatibility for legacy edge cases.