server {
    listen 80;
    root /usr/share/nginx/html;

    # Nginx's bundled mime.types does not name the APK type on every build, and
    # a wrong Content-Type is enough for a download manager to save an HTML
    # error page under the right filename. Say it explicitly.
    types {
        application/json                          json;
        application/vnd.android.package-archive   apk;
    }
    default_type application/octet-stream;

    # The manifest changes every release; the APKs never do, because a new
    # release is a new filename. Cache accordingly.
    location = /manifest.json {
        add_header Cache-Control "no-cache";
    }
    location ~ \.apk$ {
        add_header Cache-Control "public, max-age=31536000, immutable";
    }

    # Nothing here is a secret, but nothing here is a directory listing either.
    autoindex off;

    location / {
        try_files $uri =404;
    }
}