Serving llama-swap under a reverse proxy subpath

llama-swap serves everything from its own root (/ui, /v1, /api, ...) and has no base-path setting. To reach it at https://host/asubpath/llama-swap/, configure the proxy to strip the prefix before forwarding. The UI requests its assets and API endpoints relative to the page, so it follows the prefix automatically.

nginx

location /asubpath/llama-swap/ {
    proxy_pass http://127.0.0.1:8080/;   # trailing slash strips the prefix
    proxy_read_timeout 3600s;            # streams are long-lived
}

The trailing slash on proxy_pass is what does the rewrite; without it llama-swap receives /asubpath/llama-swap/... and answers 404.

Caddy

handle_path /asubpath/llama-swap/* {
    reverse_proxy localhost:8080
}

handle_path strips the matched prefix; plain handle does not.

What breaks without stripping

If the prefix is forwarded instead of stripped, llama-swap answers 404 for everything, because it only registers routes at its own root. Do not "fix" this by routing /ui and /api at the proxy root too; the prefix must be stripped on the way in and re-added by the browser on the way back, which is exactly what a strip rewrite does.

Also always include the trailing slash in client URLs (https://host/asubpath/llama-swap/, not .../llama-swap): redirects on server responses are emitted relative to that URL, and a missing slash lets the browser resolve them one directory up.