How I built a production AI SaaS as a solo developer

I built Statementory to review UCAS personal statements with AI. Score out of 100, line-by-line annotations, rewrites, improvement plan. The kind of feedback a good teacher gives you, available at 2am the night before the deadline. Here's what I learned building it solo. Everything flows from one constraint: the AI takes 5 minutes Claude processing a full personal statement and generating structured feedback takes 5 to 10 minutes. Vercel serverless functions timeout at 10 to 60 seconds depending