Cloudflare Pages

"records": { "CNAME": "you-project.pages.dev" }

Replace you-project with your Pages project's own *.pages.dev subdomain, shown at the top of the project in the Cloudflare dashboard.

Two ways to apply this. The quickest is runs-at.dev/manage: sign in, pick the record type, paste the value, save. It writes the same commit to the registry and DNS follows within seconds. The steps below do it by pull request instead, which is what you want if you would rather review the change first. Either way handles subdomains entries.

1. Fork the registry and edit domains/you.json to the record above.
2. Open a pull request. Once merged, the CNAME is synced to DNS automatically.
3. In the Cloudflare dashboard: your Pages project → Custom domains → Set up a custom domain → you.runs-at.dev. Cloudflare issues the certificate once it can see the CNAME.

Custom domains shows "Active" for you.runs-at.dev once the certificate is issued. Visiting https://you.runs-at.dev should then serve the project.