diff --git a/docs/assets/nginx.conf b/docs/assets/nginx.conf
new file mode 100644
index 0000000..9a108d4
--- /dev/null
+++ b/docs/assets/nginx.conf
@@ -0,0 +1,619 @@
+user nginx;
+pid /var/run/nginx.pid;
+
+
+worker_processes auto;
+worker_rlimit_nofile 300000; # needs to be < ulimit -n
+
+error_log /data/nginx/logs/nginx-error.log warn;
+
+events {
+    worker_connections 40000;
+    multi_accept on;
+}
+
+http {
+    # aggressive caching for read-only sources
+    open_file_cache max=1000000 inactive=60m;
+    open_file_cache_valid 60m;
+    open_file_cache_min_uses 1;
+    open_file_cache_errors on;
+
+    server_tokens off;
+
+    include /etc/nginx/mime.types;
+    types {
+        application/x-protobuf pbf;
+    }
+    default_type application/octet-stream;
+
+    charset utf-8;
+
+    sendfile on;
+    tcp_nopush on;
+    tcp_nodelay on;
+
+    reset_timedout_connection on;
+    send_timeout 20;
+
+    max_ranges 0;
+
+    gzip on;
+    gzip_comp_level 1;
+    gzip_types application/json application/x-protobuf;
+
+    log_format access_json '{'
+
+    # general
+    '"time": "$time_iso8601", '
+    '"status": $status, '
+    #'"request_method": "$request_method", '
+    #'"uri": "$uri", '
+    #'"request": "$request", '
+    #'"request_time": $request_time, '
+    '"body_bytes_sent": $body_bytes_sent, '
+    '"http_referrer": "$http_referer", '
+    '"http_user_agent": "$http_user_agent", '
+    #'"scheme": "$scheme", '
+    #'"host": "$host", '
+    #'"http_host": "$http_host", '
+
+    # IP address related
+    # IP address logging is disabled
+    #'"remote_addr": "$remote_addr", '
+    #'"http_x_forwarded_for": "$http_x_forwarded_for", '
+
+    # CF related
+    #'"http_cf_ray": "$http_cf_ray", '
+    #'"http_cf_ipcountry": "$http_cf_ipcountry", '
+    #'"http_cf_connecting_ip": "$http_cf_connecting_ip", '
+
+    '"_": "_"' # helper for no trailing comma
+    '}';
+
+    access_log off;
+    #access_log /data/nginx/logs/nginx-access.log access_json buffer=128k;
+
+    include /data/nginx/config/*;
+    include /data/nginx/sites/*;
+}
+
+# configuration file /etc/nginx/mime.types:
+types {
+
+    # Data interchange
+
+    application/atom+xml atom;
+    application/json json map topojson;
+    application/ld+json jsonld;
+    application/rss+xml rss;
+    # Normalize to standard type.
+    # https://tools.ietf.org/html/rfc7946#section-12
+    application/geo+json geojson;
+    application/xml xml;
+    # Normalize to standard type.
+    # https://tools.ietf.org/html/rfc3870#section-2
+    application/rdf+xml rdf;
+
+
+    # JavaScript
+
+    # Servers should use text/javascript for JavaScript resources.
+    # https://html.spec.whatwg.org/multipage/scripting.html#scriptingLanguages
+    text/javascript js mjs;
+    application/wasm wasm;
+
+
+    # Manifest files
+
+    application/manifest+json webmanifest;
+    application/x-web-app-manifest+json webapp;
+    text/cache-manifest appcache;
+
+
+    # Media files
+
+    audio/midi mid midi kar;
+    audio/mp4 aac f4a f4b m4a;
+    audio/mpeg mp3;
+    audio/ogg oga ogg opus;
+    audio/x-realaudio ra;
+    audio/x-wav wav;
+    image/apng apng;
+    image/avif avif avifs;
+    image/bmp bmp;
+    image/gif gif;
+    image/jpeg jpeg jpg;
+    image/jxl jxl;
+    image/jxr jxr hdp wdp;
+    image/png png;
+    image/svg+xml svg svgz;
+    image/tiff tif tiff;
+    image/vnd.wap.wbmp wbmp;
+    image/webp webp;
+    image/x-jng jng;
+    video/3gpp 3gp 3gpp;
+    video/mp4 f4p f4v m4v mp4;
+    video/mpeg mpeg mpg;
+    video/ogg ogv;
+    video/quicktime mov;
+    video/webm webm;
+    video/x-flv flv;
+    video/x-mng mng;
+    video/x-ms-asf asf asx;
+    video/x-msvideo avi;
+
+    # Serving `.ico` image files with a different media type
+    # prevents Internet Explorer from displaying then as images:
+    # https://github.com/h5bp/html5-boilerplate/commit/37b5fec090d00f38de64b591bcddcb205aadf8ee
+
+    image/x-icon cur ico;
+
+
+    # Microsoft Office
+
+    application/msword doc;
+    application/vnd.ms-excel xls;
+    application/vnd.ms-powerpoint ppt;
+    application/vnd.openxmlformats-officedocument.wordprocessingml.document docx;
+    application/vnd.openxmlformats-officedocument.spreadsheetml.sheet xlsx;
+    application/vnd.openxmlformats-officedocument.presentationml.presentation pptx;
+
+
+    # Web fonts
+
+    font/woff woff;
+    font/woff2 woff2;
+    application/vnd.ms-fontobject eot;
+    font/ttf ttf;
+    font/collection ttc;
+    font/otf otf;
+
+
+    # Other
+
+    application/java-archive ear jar war;
+    application/mac-binhex40 hqx;
+    application/octet-stream bin deb dll dmg exe img iso msi msm msp safariextz;
+    application/pdf pdf;
+    application/postscript ai eps ps;
+    application/rtf rtf;
+    application/vnd.google-earth.kml+xml kml;
+    application/vnd.google-earth.kmz kmz;
+    application/vnd.wap.wmlc wmlc;
+    application/x-7z-compressed 7z;
+    application/x-bb-appworld bbaw;
+    application/x-bittorrent torrent;
+    application/x-chrome-extension crx;
+    application/x-cocoa cco;
+    application/x-java-archive-diff jardiff;
+    application/x-java-jnlp-file jnlp;
+    application/x-makeself run;
+    application/x-opera-extension oex;
+    application/x-perl pl pm;
+    application/x-pilot pdb prc;
+    application/x-rar-compressed rar;
+    application/x-redhat-package-manager rpm;
+    application/x-sea sea;
+    application/x-shockwave-flash swf;
+    application/x-stuffit sit;
+    application/x-tcl tcl tk;
+    application/x-x509-ca-cert crt der pem;
+    application/x-xpinstall xpi;
+    application/xhtml+xml xhtml;
+    application/xslt+xml xsl;
+    application/zip zip;
+    text/calendar ics;
+    text/css css;
+    text/csv csv;
+    text/html htm html shtml;
+    text/markdown md markdown;
+    text/mathml mml;
+    text/plain txt;
+    text/vcard vcard vcf;
+    text/vnd.rim.location.xloc xloc;
+    text/vnd.sun.j2me.app-descriptor jad;
+    text/vnd.wap.wml wml;
+    text/vtt vtt;
+    text/x-component htc;
+
+}
+
+# configuration file /data/nginx/sites/default_disable.conf:
+map "" $empty {
+    default "";
+}
+
+server {
+    listen 80 default_server;
+    listen [::]:80 default_server;
+
+    listen 443 ssl default_server;
+    listen [::]:443 ssl default_server;
+    http2 on;
+
+    server_name _;
+
+    ssl_ciphers aNULL;
+    ssl_certificate /etc/nginx/ssl/dummy.crt;
+    ssl_certificate_key /etc/nginx/ssl/dummy.key;
+
+    return 444;
+}
+
+# configuration file /data/nginx/sites/ofm_roundrobin.conf:
+server {
+    server_name ofm_roundrobin tiles.openfreemap.org;
+
+    # ssl: https://ssl-config.mozilla.org / intermediate config
+
+    listen 80;
+    listen 443 ssl;
+    listen [::]:443 ssl;
+    http2 on;
+
+    ssl_certificate /data/nginx/certs/ofm_roundrobin.cert;
+    ssl_certificate_key /data/nginx/certs/ofm_roundrobin.key;
+
+    ssl_session_timeout 1d;
+    ssl_session_cache shared:MozSSL:10m; # about 40000 sessions
+    ssl_session_tickets off;
+
+    ssl_dhparam /etc/nginx/ffdhe2048.txt;
+
+    # intermediate configuration
+    ssl_protocols TLSv1.2 TLSv1.3;
+    ssl_ciphers ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:DHE-RSA-CHACHA20-POLY1305;
+    ssl_prefer_server_ciphers off;
+
+    # access log doesn't contain IP address
+    access_log off;
+    #access_log /data/ofm/http_host/logs_nginx/roundrobin-access.jsonl access_json buffer=128k;
+
+    error_log /data/ofm/http_host/logs_nginx/roundrobin-error.log;
+
+    add_header X-Robots-Tag "noindex, nofollow" always;
+
+
+    # specific JSON monaco 20250806_231001_pt
+    location = /monaco/20250806_231001_pt {
+        # no trailing slash
+        alias /data/ofm/http_host/runs/monaco/20250806_231001_pt/tilejson-ofm_roundrobin.json; # no trailing slash
+
+        expires 1w;
+        default_type application/json;
+
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header Cache-Control public;
+        add_header X-Robots-Tag "noindex, nofollow" always;
+
+        add_header x-ofm-debug 'specific JSON monaco 20250806_231001_pt';
+    }
+
+    # specific PBF monaco 20250806_231001_pt
+    location ^~ /monaco/20250806_231001_pt/ {
+        # trailing slash
+        alias /mnt/ofm/monaco-20250806_231001_pt/tiles/; # trailing slash
+        try_files $uri @empty_tile;
+        add_header Content-Encoding gzip;
+
+        expires 10y;
+
+        types {
+            application/vnd.mapbox-vector-tile pbf;
+        }
+
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header Cache-Control public;
+        add_header X-Robots-Tag "noindex, nofollow" always;
+
+        add_header x-ofm-debug 'specific PBF monaco 20250806_231001_pt';
+    }
+
+    # specific JSON planet 20250806_001001_pt
+    location = /planet/20250806_001001_pt {
+        # no trailing slash
+        alias /data/ofm/http_host/runs/planet/20250806_001001_pt/tilejson-ofm_roundrobin.json; # no trailing slash
+
+        expires 1w;
+        default_type application/json;
+
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header Cache-Control public;
+        add_header X-Robots-Tag "noindex, nofollow" always;
+
+        add_header x-ofm-debug 'specific JSON planet 20250806_001001_pt';
+    }
+
+    # specific PBF planet 20250806_001001_pt
+    location ^~ /planet/20250806_001001_pt/ {
+        # trailing slash
+        alias /mnt/ofm/planet-20250806_001001_pt/tiles/; # trailing slash
+        try_files $uri @empty_tile;
+        add_header Content-Encoding gzip;
+
+        expires 10y;
+
+        types {
+            application/vnd.mapbox-vector-tile pbf;
+        }
+
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header Cache-Control public;
+        add_header X-Robots-Tag "noindex, nofollow" always;
+
+        add_header x-ofm-debug 'specific PBF planet 20250806_001001_pt';
+    }
+
+    # specific JSON monaco 20250805_231001_pt
+    location = /monaco/20250805_231001_pt {
+        # no trailing slash
+        alias /data/ofm/http_host/runs/monaco/20250805_231001_pt/tilejson-ofm_roundrobin.json; # no trailing slash
+
+        expires 1w;
+        default_type application/json;
+
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header Cache-Control public;
+        add_header X-Robots-Tag "noindex, nofollow" always;
+
+        add_header x-ofm-debug 'specific JSON monaco 20250805_231001_pt';
+    }
+
+    # specific PBF monaco 20250805_231001_pt
+    location ^~ /monaco/20250805_231001_pt/ {
+        # trailing slash
+        alias /mnt/ofm/monaco-20250805_231001_pt/tiles/; # trailing slash
+        try_files $uri @empty_tile;
+        add_header Content-Encoding gzip;
+
+        expires 10y;
+
+        types {
+            application/vnd.mapbox-vector-tile pbf;
+        }
+
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header Cache-Control public;
+        add_header X-Robots-Tag "noindex, nofollow" always;
+
+        add_header x-ofm-debug 'specific PBF monaco 20250805_231001_pt';
+    }
+
+    # specific JSON planet 20250730_001001_pt
+    location = /planet/20250730_001001_pt {
+        # no trailing slash
+        alias /data/ofm/http_host/runs/planet/20250730_001001_pt/tilejson-ofm_roundrobin.json; # no trailing slash
+
+        expires 1w;
+        default_type application/json;
+
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header Cache-Control public;
+        add_header X-Robots-Tag "noindex, nofollow" always;
+
+        add_header x-ofm-debug 'specific JSON planet 20250730_001001_pt';
+    }
+
+    # specific PBF planet 20250730_001001_pt
+    location ^~ /planet/20250730_001001_pt/ {
+        # trailing slash
+        alias /mnt/ofm/planet-20250730_001001_pt/tiles/; # trailing slash
+        try_files $uri @empty_tile;
+        add_header Content-Encoding gzip;
+
+        expires 10y;
+
+        types {
+            application/vnd.mapbox-vector-tile pbf;
+        }
+
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header Cache-Control public;
+        add_header X-Robots-Tag "noindex, nofollow" always;
+
+        add_header x-ofm-debug 'specific PBF planet 20250730_001001_pt';
+    }
+
+
+    # latest JSON monaco
+    location = /monaco {
+        # no trailing slash
+        alias /data/ofm/http_host/runs/monaco/20250806_231001_pt/tilejson-ofm_roundrobin.json; # no trailing slash
+
+        expires 1d;
+        default_type application/json;
+
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header Cache-Control public;
+        add_header X-Robots-Tag "noindex, nofollow" always;
+
+        add_header x-ofm-debug 'latest JSON monaco';
+    }
+
+
+    # wildcard JSON monaco
+    location ~ ^/monaco/([^/]+)$ {
+        # regex location is unreliable with alias, only root is reliable
+
+        root /data/ofm/http_host/runs/monaco/20250806_231001_pt; # no trailing slash
+        try_files /tilejson-ofm_roundrobin.json =404;
+
+        expires 1w;
+        default_type application/json;
+
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header Cache-Control public;
+        add_header X-Robots-Tag "noindex, nofollow" always;
+
+        add_header x-ofm-debug 'wildcard JSON monaco';
+    }
+
+    # wildcard PBF monaco
+    location ~ ^/monaco/([^/]+)/(.+)$ {
+        # regex location is unreliable with alias, only root is reliable
+
+        root /mnt/ofm/monaco-20250806_231001_pt/tiles/; # trailing slash
+        try_files /$2 @empty_tile;
+        add_header Content-Encoding gzip;
+
+        expires 10y;
+
+        types {
+            application/vnd.mapbox-vector-tile pbf;
+        }
+
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header Cache-Control public;
+        add_header X-Robots-Tag "noindex, nofollow" always;
+
+        add_header x-ofm-debug 'wildcard PBF monaco';
+    }
+
+
+    # latest JSON planet
+    location = /planet {
+        # no trailing slash
+        alias /data/ofm/http_host/runs/planet/20250806_001001_pt/tilejson-ofm_roundrobin.json; # no trailing slash
+
+        expires 1d;
+        default_type application/json;
+
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header Cache-Control public;
+        add_header X-Robots-Tag "noindex, nofollow" always;
+
+        add_header x-ofm-debug 'latest JSON planet';
+    }
+
+
+    # wildcard JSON planet
+    location ~ ^/planet/([^/]+)$ {
+        # regex location is unreliable with alias, only root is reliable
+
+        root /data/ofm/http_host/runs/planet/20250806_001001_pt; # no trailing slash
+        try_files /tilejson-ofm_roundrobin.json =404;
+
+        expires 1w;
+        default_type application/json;
+
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header Cache-Control public;
+        add_header X-Robots-Tag "noindex, nofollow" always;
+
+        add_header x-ofm-debug 'wildcard JSON planet';
+    }
+
+    # wildcard PBF planet
+    location ~ ^/planet/([^/]+)/(.+)$ {
+        # regex location is unreliable with alias, only root is reliable
+
+        root /mnt/ofm/planet-20250806_001001_pt/tiles/; # trailing slash
+        try_files /$2 @empty_tile;
+        add_header Content-Encoding gzip;
+
+        expires 10y;
+
+        types {
+            application/vnd.mapbox-vector-tile pbf;
+        }
+
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header Cache-Control public;
+        add_header X-Robots-Tag "noindex, nofollow" always;
+
+        add_header x-ofm-debug 'wildcard PBF planet';
+    }
+
+    location /fonts/ {
+        # trailing slash
+
+        alias /data/ofm/http_host/assets/fonts/ofm/; # trailing slash
+        try_files $uri =404;
+
+        expires 1w;
+
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header Cache-Control public;
+        add_header X-Robots-Tag "noindex, nofollow" always;
+
+    }
+
+    location /natural_earth/ {
+        # trailing slash
+
+        alias /data/ofm/http_host/assets/natural_earth/ofm/; # trailing slash
+        try_files $uri =404;
+
+        expires 10y;
+
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header Cache-Control public;
+        add_header X-Robots-Tag "noindex, nofollow" always;
+
+    }
+
+    location /sprites/ {
+        # trailing slash
+
+        alias /data/ofm/http_host/assets/sprites/; # trailing slash
+        try_files $uri =404;
+
+        expires 10y;
+
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header Cache-Control public;
+        add_header X-Robots-Tag "noindex, nofollow" always;
+
+    }
+
+
+    # we need to handle missing tiles as valid request returning empty string
+    location @empty_tile {
+        return 200 '';
+
+        expires 10y;
+
+        types {
+            application/vnd.mapbox-vector-tile pbf;
+        }
+
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header Cache-Control public;
+        add_header X-Robots-Tag "noindex, nofollow" always;
+
+        add_header x-ofm-debug 'empty tile';
+    }
+
+    location = / {
+        return 302 https://openfreemap.org;
+    }
+
+
+    location /styles/ {
+        # trailing slash
+
+        alias /data/ofm/http_host/assets/styles/ofm/; # trailing slash
+        try_files $uri.json =404;
+
+        expires 1d;
+        default_type application/json;
+
+        # substitute the domain in the TileJSON
+        sub_filter '__TILEJSON_DOMAIN__' 'tiles.openfreemap.org';
+        sub_filter_once off;
+        sub_filter_types '*';
+
+        add_header 'Access-Control-Allow-Origin' '*' always;
+        add_header Cache-Control public;
+        add_header X-Robots-Tag "noindex, nofollow" always;
+
+    }
+
+    # catch-all block to deny all other requests
+    location / {
+        deny all;
+        error_log /data/ofm/http_host/logs_nginx/roundrobin-deny.log error;
+    }
+}
+