Custom domains

Every web deploy gets a free URL at https://<slug>.contrast.run, for example https://acme-store.contrast.run. It is live the moment your deploy finishes, and it is enough to share and test.

To serve the same app from a domain you own, such as www.example.com, attach a custom domain. Contrast points your domain at the deploy, provisions an SSL certificate, and keeps them attached across redeploys.

#What you need

• Active production hosting for the project. Hosting is $10/mo per live web project and includes one custom domain. Run usage is not currently charged. Attaching needs a billing role on the account: owner, admin, or billing.
• A live web deploy. Publish the app first (see Publish), then attach the domain.
• A domain you own, plus access to its DNS records at your registrar.

You attach one domain per project. Enter the exact hostname you want to serve, for example www.example.com or the root example.com.

#Attach a domain

1. Open Deploy pane → Web → Custom domain.
2. Type your domain in the field, for example www.example.com, and press Attach.
3. Contrast shows a single DNS record to add. The status starts at Pending DNS.

#Add the DNS record

Add one CNAME record at your registrar. Contrast gives you the exact target and a Copy button next to it.

Type:  CNAME
Name:  www          (or @ for a root domain)
Value: <slug>.domains.contrast.dev

For a slug of acme-store, the value is acme-store.domains.contrast.dev. Copy the target from the Custom domain panel rather than typing it, so the slug always matches your live deploy.

For a root or apex domain (example.com with no www), most registrars will not accept a plain CNAME at the root. Use your registrar’s CNAME flattening or ALIAS record type instead, pointing at the same target.

#Automatic SSL

Once your DNS record resolves, Contrast issues an SSL certificate for the domain automatically. You do not upload or renew anything. The status moves through Issuing cert while the certificate is provisioned, then to Active when the domain serves over HTTPS.

#Status states

The Custom domain panel shows a colored dot and a label. Press Refresh to re-check after you change DNS.

#If it stays pending

• Confirm the record. At your registrar, check the CNAME name and value match the panel exactly. A trailing dot or an extra www is enough to break it.
• Wait for propagation. DNS changes can take up to an hour, sometimes longer, to reach Contrast. Press Refresh to re-check rather than re-attaching.
• Check apex handling. If the domain is a root domain, confirm you used CNAME flattening or an ALIAS record, since a plain root CNAME is rejected by most registrars.
• Verify from a terminal. Run dig www.example.com CNAME +short. It should return <slug>.domains.contrast.dev.

#Remove a domain

1. Open Deploy pane → Web → Custom domain.
2. Press Remove and confirm.

Removing a domain stops it routing to your app right away. Production hosting continues on <slug>.contrast.run, and you can attach the domain again later.