I migrated my 9-year-old newsletter with Claude Code and Codex and turning it into a SaaS -- could never have done it without vibecoding

I've run AI Weekly for five years now. Roughly 500 issues, three sends a week, a bit over 50,000 subscribers. For those years it lived on a hosted newsletter platform and I wrote copy into a text box. The main frustration was not being able to add features