Domains & subdomains

#Wildcard subdomains

Every site answers on its subdomains automatically, up to four levels deep. If acme.test is a site, all of these reach it:

tenant1.acme.test
api.acme.test
eu.tenant1.acme.test

This works for multi-tenant apps and subdomain routing without any configuration, on every platform.

On Windows, a group policy or a VPN can override the rule that sends *.test to Flock. Then only the site names and the extra domains you add (below) resolve, through the hosts file, and Flock tells you so. Linux has no such fallback: if a VPN or another resolver takes over .test lookups, sites don't open until it's fixed, and Flock tells you that too.

#Extra domains and aliases

Give a site additional domains. A name without a dot is treated as a subdomain of the site, and a full name ending in your TLD is added as an alias.

AppCLI

In Settings → Sites, select the site and click Add Domain… under Domains in its Site section. Enter tenant1 for tenant1.acme.test, or a full name like acme-admin.test for a separate alias, and click Add.

Extra domains are listed under Domains, with aliases marked (alias). To remove one, click the minus button next to it and confirm with Remove.

# Run inside the project, or pass the site name as the second argument
flock domain add tenant1          # tenant1.acme.test
flock domain add acme-admin.test  # a completely separate alias
flock domain list
flock domain remove acme-admin.test

An alias can also sit under another site's domain. If another project has the alias accounts.acme.test, that name and its subdomains reach that project, and the rest of *.acme.test still reaches acme.

#How .test resolution works

Flock runs its own small DNS server, so new sites resolve instantly without changing your hosts file:

• macOS: /etc/resolver/test sends .test lookups to Flock's DNS server on port 53535. Because the port is unprivileged, the DNS server doesn't need root.
• Windows: a name-resolution policy rule sends *.test to Flock. A small helper service also writes your sites into a # BEGIN Flock block in the hosts file as a fallback.
• Linux: a systemd-resolved drop-in, /etc/systemd/resolved.conf.d/flock.conf, sends only .test lookups to Flock's DNS server on port 53535.