Earlier this year I migrated the analytics backend behind this site from a long-running Express server on Railway to a set of Vercel Functions. The frontend never noticed. Cost dropped from a small monthly Railway bill to $0/month on Vercel's hobby tier.
Source: [Dev.to](https://dev.to/gabbs279/migrating-an-express-backend-to-vercel-functions-without-downtime-3kal)