Reverse Proxy Patterns: Architectures for Scalable Web Applications
Centralized traffic control with reverse proxies
Reverse proxies are a foundational building block of modern web infrastructure. They sit in front of backend services, acting as an intermediary that controls how traffic enters your system.
From load balancing and TLS termination to security enforcement and observability, reverse proxies enable scalability and resilience at internet scale.
What Is a Reverse Proxy?
A reverse proxy is a server that receives client requests and forwards them to one or more backend servers on behalf of the client.
Clients talk to the proxy — the proxy talks to your services.
This abstraction allows internal architectures to evolve without exposing backend topology to the public internet.
Reverse Proxy vs Forward Proxy
| Aspect | Reverse Proxy | Forward Proxy |
|---|---|---|
| Position | In front of servers | In front of clients |
| Primary role | Protect and scale backends | Control outbound traffic |
| Visibility | Transparent to clients | Explicitly configured |
Common Reverse Proxy Patterns
Load Balancing
Distributes incoming traffic across multiple backend instances, improving availability and throughput.
- Round-robin
- Least connections
- Hash-based routing
TLS Termination
Handles HTTPS encryption at the proxy layer, reducing computational overhead on backend services.
Path-Based Routing
Routes requests to different services based on URL paths or hostnames.
/api → API service /static → CDN or asset server
Security-Focused Proxy Patterns
- IP allowlists and blocklists
- Rate limiting and throttling
- Web Application Firewall (WAF)
- Authentication and authorization gateways
Reverse proxies often act as the first security enforcement point in zero-trust architectures.
Caching and Performance Optimization
Proxies can cache responses close to users, reducing backend load and improving latency.
- Static asset caching
- API response caching
- Header-based cache control
Reverse Proxies in Microservices
In microservice environments, reverse proxies are often combined with API gateways and service meshes.
- North-south traffic handling
- Protocol translation (HTTP ↔ gRPC)
- Centralized observability
Popular tools include NGINX, HAProxy, Envoy, and Traefik.
Common Mistakes to Avoid
- Overloading the proxy with business logic
- Missing timeout and retry configuration
- Improper header forwarding
- Single point of failure deployments
Reverse proxies must be treated as critical infrastructure and deployed redundantly.
Best Practices
- Deploy proxies in highly available configurations
- Use health checks and circuit breakers
- Centralize TLS and security policies
- Monitor latency, error rates, and saturation
Final Thoughts
Reverse proxies are far more than simple traffic routers. They are strategic control points that shape performance, security, and reliability.
When designed correctly, reverse proxy patterns enable scalable architectures that evolve safely over time.
