Caddy Routing Test Results

Nested subdomains resolve correctly:

$ ping brain.ui.localhost
PING localhost (127.0.0.1)

macOS resolves *.localhost including nested subdomains to 127.0.0.1 (RFC 6761).

Nested subdomain:

brain.ui.localhost {
    reverse_proxy localhost:7805
    tls internal
}

Path-based:

test.localhost {
    tls internal
    handle_path /brain/* {
        reverse_proxy localhost:7805
    }
    handle_path /static/* {
        reverse_proxy localhost:7940
    }
}

Gradio uses relative paths: src="./assets/index-xxx.js"

Method	Browser resolves to	Result
Nested	/assets/index-xxx.js	200 OK
Path-based	/brain/assets/index-xxx.js	200 OK (handle_path catches it)

Both methods work. Choose based on preference:

If you want...	Use
Clean URLs, easy bookmarking	brain.ui.localhost (nested)
Fewer DNS entries, grouped services	ui.localhost/brain/ (path-based)
Current setup (works fine)	brain.localhost (flat)