Proxy Admaxxer Through NGINX

NGINX's proxy_pass directive is one of the most battle-tested ways to route pixel requests through your own infrastructure. Two location blocks are all that is needed to forward /js/script.js and /api/event to Admaxxer while keeping your domain as the public-facing host.

Why Proxy?

Ad-blocker bypass. Browser extensions block known tracking hostnames. Routing via NGINX on your own domain puts requests outside those blocklists.
Performance. NGINX is extremely efficient at reverse proxying — the overhead is typically under 0.5 ms even under heavy load.
Full control. You can add custom headers, rate limiting, access logging, and caching at the NGINX layer without touching application code.
Universal. Works for any application behind NGINX — Node.js, PHP, Python, Rails, static sites, or bare HTML.

Prerequisites

NGINX 1.14+ with ngx_http_proxy_module (included in all standard builds).
Root or sudo access to edit the NGINX server block config.
Your Admaxxer workspace ID from Connections › Install.

Step 1 — Add Location Blocks

Open your NGINX server block config (typically /etc/nginx/sites-available/yourdomain.conf or /etc/nginx/conf.d/yourdomain.conf) and add inside the server { } block:

server {
    listen 443 ssl http2;
    server_name yourdomain.com;
    # ... your existing SSL config, root, etc. ...

    # Admaxxer pixel proxy
    location = /js/script.js {
        proxy_pass         https://admaxxer.com/js/script.js;
        proxy_ssl_server_name on;
        proxy_set_header   Host admaxxer.com;
        proxy_set_header   X-Real-IP $remote_addr;
        proxy_set_header   X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_cache_bypass 1;
        add_header         Cache-Control "public, max-age=3600";
    }

    location ^~ /api/event {
        proxy_pass         https://admaxxer.com/api/event;
        proxy_ssl_server_name on;
        proxy_set_header   Host admaxxer.com;
        proxy_set_header   X-Real-IP $remote_addr;
        proxy_set_header   X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_read_timeout 10s;
    }
}

Key directives explained:

proxy_ssl_server_name on — enables SNI for the upstream TLS handshake. Required when proxying to an HTTPS upstream.
proxy_set_header Host admaxxer.com — sends the correct Host header to the upstream. Without this, the request may fail SNI verification.
location = /js/script.js — the = modifier is an exact match; it takes priority over longer prefix matches.
location ^~ /api/event — the ^~ modifier matches any path starting with /api/event and prevents regex locations from overriding it.

Step 2 — Test and Reload NGINX

sudo nginx -t
sudo systemctl reload nginx

Always run nginx -t before reloading. A syntax error in the config will prevent the reload and leave the old config running.

Step 3 — Update the Admaxxer Snippet

In Admaxxer go to Connections › Install, enable Custom proxy domain, and enter your domain. Copy the regenerated snippet into your site's <head>.

Step 4 — Test the Proxy

# Script
curl -I https://yourdomain.com/js/script.js
# Expect: HTTP/2 200  content-type: application/javascript

# Event endpoint
curl -X POST https://yourdomain.com/api/event \
  -H 'Content-Type: application/json' \
  -d '{"name":"pageview","url":"https://yourdomain.com/"}'
# Expect: HTTP/2 200 or 204

Optional: Add DNS Resolver for Upstream

If NGINX cannot resolve admaxxer.com at startup (e.g., in a container environment), add a resolver directive:

resolver 8.8.8.8 1.1.1.1 valid=60s;
resolver_timeout 5s;

Add this inside the server { } block or in the http { } block in nginx.conf.

Optional: Cache the Script File

The pixel script changes infrequently. You can cache it in NGINX's proxy cache to reduce upstream requests:

# In http { } block (nginx.conf)
proxy_cache_path /tmp/nginx-cache levels=1:2 keys_zone=admaxxer_cache:1m max_size=10m;

# In location = /js/script.js
proxy_cache        admaxxer_cache;
proxy_cache_valid  200 1h;
proxy_cache_use_stale error timeout updating;

Troubleshooting

502 Bad Gateway. NGINX cannot reach admaxxer.com. Check outbound firewall rules: curl -I https://admaxxer.com/js/script.js from the server. Also verify proxy_ssl_server_name on is present.
SSL_do_handshake error in error.log. The upstream TLS handshake failed. Add proxy_ssl_verify off; temporarily to diagnose (do not use in production). Permanent fix: ensure proxy_ssl_server_name on and that the server's CA bundle is up to date.
Location block not matched. Use nginx -T | grep location to list all active location blocks. Make sure there is no conflicting catch-all location earlier in the file.
POST requests to /api/event return 405. Your upstream app may have its own /api/event route. If the proxy location is overridden by a file-system route, adjust the location order or remove the conflicting route.

Rollback

Remove or comment out the two location blocks, run nginx -t, and reload NGINX. Disable the custom proxy domain in Admaxxer to revert the snippet.

Other Proxy Guides

Cloudflare · Vercel · Next.js · Nuxt · Netlify · WordPress · Apache

See also: Connections › Install for the base snippet.