The backend rewrite of Leverage OJ was already underway — clean architecture, proper migrations, real auth — but the frontend was still the original codebase: a Vue 2 app with scattered API calls, no type safety, and a build pipeline that took creativity to coax into working. If you're going to fix the foundation, you might as well fix the roof too.

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Some projects accumulate debt quietly. Leverage OJ was not one of them — it accumulated it loudly, in the form of a ranking system that froze mid-competition, an auth system that broke under PM2 clustering, a leaderboard that scanned the entire submissions table on every request, and a password hashing scheme that was one config leak away from a full credential dump.