How we run Vercel's CDN in front of Discourse

This post details how Vercel's CDN can be used as a proxy for external applications like Discourse, providing security (Firewall, Bot Management) and observability (Web Analytics) without requiring a full migration. It introduces the use of `vercel.ts` for rewrites to proxy traffic to an inner host with a `x-proxy-secret` header for validation. It also expands on the microfrontend approach by using `microfrontends.json` to mount separate Vercel projects to specific routes (e.g., `/live/:path*`, `/.well-known/workflow/:path*`) for better isolation, independent environment variables, and organization, enabling incremental modernization of parts of the application.