Reverse Proxies for Web Performance & Security: A Guide

A reverse proxy is one of those pieces of infrastructure most people use every day without realizing it. If you've ever hit a Cloudflare-fronted site, an Nginx-backed API, or a load-balanced app, your request passed through one. This guide covers what a reverse proxy actually does, where it helps performance and security, and how to configure a basic one yourself — with working config you can copy.

One quick clarification up front, because the two get confused: a reverse proxy sits in front of your own servers and represents them to the internet. A forward proxy (the kind used for scraping, geo-testing, or privacy) sits in front of clients and represents them to the wider web. If you're here for the client-side kind, our guide to proxy servers is the better starting point. This article is about the server-side variety.

What a reverse proxy actually is

A reverse proxy is a server that accepts requests from the internet, decides where they should go, forwards them to one of your backend servers, and passes the response back to the client. To the outside world, the reverse proxy is your website — clients never talk to your application servers directly.

That single position — between the public internet and your backend — is what makes it useful. Because every request and response flows through it, the proxy can terminate TLS, cache responses, distribute traffic across multiple backends, rewrite paths, compress payloads, and enforce access rules. Common software in this space includes Nginx, HAProxy, Envoy, Caddy, and Traefik, plus managed services like Cloudflare and AWS's Application Load Balancer.

Here's the minimal shape of an Nginx reverse proxy that forwards traffic to a single app running on port 3000:

server {
    listen 80;
    server_name example.com;

    location / {
        proxy_pass http://127.0.0.1:3000;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto

Those X-Forwarded-* headers matter: once traffic passes through the proxy, your app would otherwise see every request as coming from the proxy's own IP. Passing the original client details forward keeps logging, rate limiting, and geolocation accurate.

How reverse proxies improve performance

Load balancing. The proxy spreads requests across a pool of backend servers so no single machine gets buried. If one backend fails a health check, traffic routes to the healthy ones. A basic upstream group looks like this:

upstream app_servers {
    server 10.0.0.11:3000;
    server 10.0.0.12:3000;
    server 10.0.0.13:3000;
}

server {
    listen 80;
    server_name example.com;

    location / {
        proxy_pass http://app_servers;
        proxy_set_header Host 

By default Nginx uses round-robin, but you can weight servers or switch to least-connections (least_conn;) for workloads with uneven request durations.

Caching. Frequently requested, rarely changing content can be served straight from the proxy without touching your application at all. This is the single biggest lever for reducing backend load. A simple static-asset cache:

proxy_cache_path /var/cache/nginx keys_zone=assets:10m max_size=1g inactive=60m;

server {
    location /static/ {
        proxy_cache assets;
        proxy_cache_valid 200 302 60m;
        proxy_cache_valid 404 1m;
        proxy_pass http

Compression and TLS offload. The proxy can gzip or Brotli-compress responses before they hit the wire, which helps users on slow connections, and it can handle the CPU cost of TLS handshakes so your application servers don't have to. Terminating TLS at the edge also centralizes certificate management to one place instead of every backend.

How reverse proxies improve security

They hide your backend. Because clients only ever see the proxy, the real IP addresses and topology of your application servers stay off the public internet. Attackers can't target what they can't address — provided your backends aren't reachable directly (bind them to a private network or firewall them to accept only proxy traffic).

Rate limiting. The proxy can cap how many requests a given client makes in a window, which blunts credential-stuffing attempts and accidental request floods:

limit_req_zone $binary_remote_addr zone=api:10m rate=10r/s;

server {
    location /api/ {
        limit_req zone=api burst=20 nodelay;
        proxy_pass http

Access control and WAF. You can allow or deny by IP, require authentication on admin routes, and layer a web application firewall (like ModSecurity) in front of your app to filter common injection and exploit patterns. Centralizing these rules at the proxy means you write them once instead of in every service.

DDoS mitigation. A reverse proxy — especially a managed edge network — can absorb and filter volumetric traffic before it reaches your origin. It won't make you immune, but it moves the first line of defense away from the servers doing real work. For a broader primer on the security side, see our overview of why reverse proxies matter.

Advanced routing tricks

Path- and host-based routing. One proxy can front many services — /api to your backend, / to a static frontend, blog.example.com to a separate host — all from a single public entry point. This is the foundation of most microservice gateways.

Geo-routing. Using a GeoIP database, the proxy can direct visitors to the nearest regional backend to cut latency. This is the same logic a CDN uses, applied at your own edge.

A/B testing and canary releases. You can split a percentage of traffic to a new build using request-based rules, then roll it out fully once it proves stable — no changes to the application code required.

Managing crawler traffic. The proxy can distinguish legitimate search-engine crawlers from unwanted automated traffic and apply different rules to each. A well-tuned proxy welcomes Googlebot while rate-limiting abusive scrapers hammering expensive endpoints.

Implementation checklist

A few practical points before you put a reverse proxy in production:

• Decide what you actually need. Pure load balancing, caching, TLS termination, and security policies each pull the configuration in slightly different directions. Start with the one problem you have today.

• Lock down your origin. A hidden backend is only hidden if it can't be reached directly. Firewall your app servers to accept connections only from the proxy.

• Automate certificate renewal. If you terminate TLS at the proxy, use Let's Encrypt with automatic renewal so certificates never lapse.

• Log and monitor. Ship proxy access and error logs to your monitoring stack. The proxy sees every request, which makes it the best vantage point for spotting slow endpoints, error spikes, and traffic anomalies.

• Keep it patched. The proxy is internet-facing, so it's a priority target. Update it on a schedule and restrict access to its management interfaces.

Where forward proxies fit in (and where Evomi comes in)

Reverse proxies protect and accelerate infrastructure you own. But plenty of legitimate work happens on the client side of the connection — collecting public data at scale, verifying that ads and prices render correctly across regions, load-testing your own services from outside your network, and running privacy-conscious research. That's the domain of forward proxies, and it's what we build at Evomi.

Our residential proxies, plus datacenter, mobile, and static ISP options, are ethically sourced and based in Switzerland, with prices starting at $0.30/GB for datacenter and $0.49/GB for residential. If your project involves choosing between rotating and fixed endpoints, our breakdown of static vs rotating proxies covers the tradeoffs. And if you'd rather not manage the plumbing at all, our Scraping Browser gives you a managed headless Chromium endpoint compatible with Playwright and Puppeteer.

Two different tools for two different jobs — a reverse proxy in front of your servers, a forward proxy in front of your clients. Knowing which side of the connection you're on is most of the battle.