# Domains: your name, the same app

Attach a domain or several subdomains to an app you already own. The names
resolve to the same files, backend resources and app identity.

You need:

- The existing app's returned `appHost`.
- Its owner bearer, held in a trusted agent or server.
- Access to DNS settings, either through the user or an already-authorized tool.

JMPKit returns exact TXT and routing records. No registrar plugin or registrar
credentials are needed to prepare the instructions. Never guess an ingress IP.
Start with DNS-only A/AAAA or CNAME routing. After the binding is active with
trusted HTTPS, a proxy such as Cloudflare may sit in front. Keep the TXT proof;
use Full (strict) with Cloudflare. Wildcards and domain purchases are separate.

The account page also exposes **Your domains** under each app. Connecting a
domain does not extend a 30-day app. Browser cookies, storage and permissions
remain specific to each origin.

## Contents

- `protocol/custom-domains-v1.md`: API, records, states, errors and safety.
- `examples.md`: short command-line workflow.
- `samples/domain-flow.mjs`: Node 22+, no dependencies.
- `samples/domain_flow.py`: Python 3 standard library.
- `samples/domain-flow.sh`: curl plus Node for safe JSON construction.

Runtime implementation: Gateway. Knowledge package: Domains starter r2.
The canonical machine-readable catalog is `/docs/kits/catalog.json`.