If you’re figuring out how to set up a custom domain for Claude Code projects, the hard part usually isn’t the code. It’s the plumbing: DNS, SSL, redirects, and the small mistakes that make a site look broken even when the app itself is fine. For teams building on Linux, this is one of those tasks that’s easy to overcomplicate and even easier to skip until the last minute.
This guide walks through the practical version: what records to create, how to connect a domain to a Linux-hosted app, when to use a subdomain versus the apex domain, and how to avoid the common launch-day traps. If you’re using a hosted environment like Vibesies, the overall workflow is the same, but the container setup can remove some of the usual sysadmin friction.
Why custom domains matter for Claude Code projects
A custom domain does more than make a project look polished. It affects trust, email deliverability, analytics, SEO, and how easy it is to hand the project to someone else later. If your Claude Code app lives at a random subdomain or temporary host, you’ll eventually spend time fixing links, redoing redirects, or explaining to users why the URL changed again.
For AI-built sites, a custom domain also creates a clean boundary between the app and the infrastructure. That matters when you’re iterating fast. You can refactor the code, swap hosting, or update the reverse proxy without changing the public URL.
How to set up a custom domain for Claude Code projects
The exact steps depend on where your site is hosted, but the pattern is always the same:
- Buy or use an existing domain from a registrar.
- Point DNS records at your hosting server or load balancer.
- Configure your web server or platform to recognize the domain.
- Issue SSL certificates.
- Test redirects, apex behavior, and www behavior.
If you’ve never done this before, the DNS step tends to be the confusing one. The good news is that you usually only need a couple of records, not a full DNS architecture.
1) Decide whether you want the apex domain or www
First choose which version should be canonical:
- Apex domain:
example.com - WWW subdomain:
www.example.com
Either can work. The important thing is to pick one and redirect the other to it. For many sites, www is simpler because it gives you more flexibility with DNS providers and CDNs. For others, especially brand sites, the bare domain looks cleaner.
Don’t leave both live as separate versions. That can create duplicate content, split analytics, and confuse search engines.
2) Add the right DNS records
Most custom domain setups use one of these patterns:
- A record for the apex domain, pointing to your server IP
- CNAME record for
www, pointing to the canonical host
Example:
@→ A →203.0.113.10www→ CNAME →example.com
Or the reverse, depending on your preferred canonical domain.
If your platform supports it, you may also need a verification record, often a TXT record, to prove ownership before SSL or routing is enabled.
Useful rule: DNS changes can take minutes or hours to propagate. Don’t assume the setup is broken after two minutes.
3) Configure your Linux app or reverse proxy
On Linux hosting, your web server needs to accept requests for the new host name. If you’re using nginx, that means updating the server_name directive. If you’re using Apache, it means setting the right ServerName and ServerAlias. If you’re behind a proxy or managed container platform, there’s usually a domain mapping step in the control plane.
At a minimum, your app should know that both of these hosts may hit the same backend:
example.comwww.example.com
Then add a redirect from the non-canonical version to the canonical one.
4) Issue SSL early, not after launch
Once the DNS is pointing correctly, enable HTTPS before you share the link publicly. Let’s Encrypt is the common choice on Linux servers, and many managed environments automate it.
Check these things:
- The certificate covers the exact domain you’re using
- The redirect goes from HTTP to HTTPS
- The certificate renews automatically
A very common launch bug is this: the site loads over HTTPS, but one image, script, or API endpoint still points to HTTP. Browsers block mixed content, and the page looks partially broken.
Common mistakes when pointing a domain at an AI-built site
Most domain problems are not “AI problems.” They’re just infrastructure issues that show up right after an app is deployed. Here are the ones I see most often.
Using the wrong DNS record type
People often try to use a CNAME at the apex domain, which many DNS providers don’t allow. If your registrar says the record is invalid, that’s usually why.
Forgetting the redirect
If both www and non-www versions load independently, search engines may treat them as separate sites. Set one canonical version and redirect the other.
Not updating app-level allowed hosts
Frameworks like Django and some other web apps require explicit allowed host settings. If the new domain isn’t whitelisted, you may get a 400 or a blank error page even though DNS is correct.
Hardcoding old URLs
After a domain change, hardcoded asset links, callback URLs, and canonical tags can keep pointing to the temporary host. Search the codebase for the old domain name before launch.
Ignoring email and verification workflows
If the site sends password resets, magic links, or webhook callbacks, those flows often depend on the base URL being correct. A broken domain can look fine in the browser while quietly breaking sign-in or notifications.
Step-by-step checklist for launch day
Here’s a practical checklist you can run through before announcing the site:
- Confirm the domain is registered and unlocked.
- Set the canonical version: apex or
www. - Add DNS records with the registrar or DNS provider.
- Wait for propagation and verify with
digornslookup. - Update the web server or platform domain mapping.
- Install or renew SSL certificates.
- Test
http://and ensure it redirects tohttps://. - Test both domain variants and confirm one redirects correctly.
- Check browser console for mixed-content warnings.
- Update any hardcoded callbacks, webhooks, and canonical tags.
If you’re the kind of person who likes to automate this, put the checklist in your repo. Claude Code can help turn it into a repeatable script or deployment note so you don’t rely on memory during future launches.
How Vibesies fits into this workflow
If you’re hosting your project in a sandboxed Linux environment, domain setup becomes much easier when the app, web server, and SSL configuration live together in one place. That’s one reason some builders use Vibesies for AI-hosted projects: the container has the operating system access you need without making you stitch together a separate app host, server login, and deployment target.
That matters most when you’re iterating on domain changes. You can update config, test redirects, and verify HTTPS behavior in the same environment where the site runs, instead of bouncing between half a dozen dashboards.
Troubleshooting: what to check when the domain still does not work
If your custom domain is still failing after the obvious steps, work through these in order:
- DNS resolution: does the domain resolve to the expected IP or host?
- Server config: does the web server recognize the host header?
- Firewall/security groups: are ports 80 and 443 open?
- SSL status: is the cert valid and not expired?
- Redirect logic: are you creating a loop between www and non-www?
- Application config: are allowed hosts, base URLs, and callback URLs updated?
If the browser shows a certificate mismatch, the domain may be pointing at the right machine but the wrong virtual host. If the browser shows a 404, the request is reaching the server but not the app route you expected. Those are different problems, and the error page usually tells you which layer is failing.
Recommended structure for long-term maintainability
If you expect to keep building on the project, keep the domain setup boring and documented. A good setup usually includes:
- One canonical public URL
- Automatic HTTP-to-HTTPS redirects
- A single source of truth for base URL settings
- Readable deployment notes in the repo
- Renewal automation for SSL
This saves time when you add a staging environment, switch servers, or hand the project to another engineer. It also makes future AI-assisted maintenance much less fragile.
Conclusion
How to set up a custom domain for Claude Code projects is mostly a matter of getting DNS, server config, and SSL to agree with each other. Once those pieces are aligned, the rest is straightforward: choose a canonical domain, redirect the alternative, verify HTTPS, and remove hardcoded URLs that still point to the old host.
That may not be the most glamorous part of shipping an AI-built site, but it’s one of the most important. A clean domain setup makes your Claude Code project look stable, keeps redirects sane, and gives you a foundation you can keep building on without constantly reworking the URL layer.