DevCatz checks most of these itself and shows a warning where the problem is — a dot on the rail, a badge in
Settings. The logs are one click away: Settings → Open logs folder (~/Library/Application Support/DevCatz/logs).
The browser says the certificate is not trusted
The rail shows a warning dot, HTTPS certificate not trusted. Go to Settings → Project → Trust certificate authority… and confirm with your password or Touch ID. Restart the browser if it still complains.
Firefox does not use the macOS Keychain by default: import ca.crt from Settings, or set
security.enterprise_roots.enabled to true in about:config.
“Could not listen on …” (the proxy is down)
Something else already listens on DevCatz’s proxy ports (8443 / 8180 by default). Find it with
lsof -nP -iTCP:8443 -sTCP:LISTEN, stop it, or change the ports in Settings → Project.
“Port N is already in use by …”
A site’s dev server cannot start because another process holds its port. Stop that process (its name is in the message), or let DevCatz assign ports for that site.
URLs without a port stopped working
Settings says The forwarder is installed but not answering. Use Disable, then Enable clean URLs… again. If it says 127.0.0.1:443 is free now, another tool (for example Laravel Herd) released that port: disable and enable again so DevCatz covers 127.0.0.1 too.
“*.yourtld does not resolve yet”
Only for a custom domain instead of .localhost. Install the resolver: Settings → General → Install resolver for
.yourtld…. If Settings says the resolver belongs to another tool, remove that tool’s file in /etc/resolver/
first — DevCatz never overwrites a resolver it did not write. .localhost itself needs no resolver.
“DNS: … on 127.0.0.1:53531”
DevCatz’s small DNS server for custom domains could not start, usually because another copy is running. Quit DevCatz completely (menu bar → Quit) and start it again.
The Docker tab says no container engine is running
Install or start one: OrbStack, Docker Desktop, Colima, Rancher Desktop, Podman or Finch. DevCatz finds whichever is running.
A version list does not load
Runtime and database versions come from their official sources (nodejs.org, go.dev, GitHub…). Rate limit, try again later means GitHub’s hourly limit for your network was reached; it resets within the hour.
DBCatz cannot connect
The connection dialog shows each step — Vault → AWS → SSH → reach → sign in — and stops at the one that failed, with a readable error. Reach failing means the host or port is wrong or blocked; sign in failing means the user, password or database.
Still stuck?
Open an issue on GitHub with what you see, your macOS version and the last lines of main.log. Remove passwords and
tokens from the log before you paste it.
Last updated 2026-10-25