server {
    listen 80;
    server_name _;
    root /usr/share/nginx/html;
    index index.html;

    # go_router owns the URL, so any path that is not a real file has to come
    # back as index.html rather than a 404 — otherwise a reload on /permissions
    # or a shared link lands on nothing.
    location / {
        try_files $uri $uri/ /index.html;
    }

    # Build output is content-hashed, the shell is not: caching index.html or
    # the service worker would pin returning workers to the previous release.
    location = /index.html {
        add_header Cache-Control "no-cache, no-store, must-revalidate";
    }
    location = /flutter_service_worker.js {
        add_header Cache-Control "no-cache, no-store, must-revalidate";
    }

    gzip on;
    gzip_types text/plain text/css application/javascript application/json image/svg+xml application/wasm;
    gzip_min_length 1024;
}