A blazingly fast, memory-efficient reverse proxy built in Rust using async I/O and designed for high-scale production workloads.

• ⚡ High Performance: Built on Tokio and Hyper for maximum throughput
• 🔄 Automatic Retries: Configurable retry logic for failed requests
• ⏱️ Smart Timeouts: Per-route and global timeout configuration
• 🔍 Health Checks: Built-in health check support for upstreams
• 📊 Metrics: Prometheus-compatible metrics for monitoring
• 🔄 Zero Downtime: Graceful shutdown support
• 🛡️ Battle-tested: Built on production-grade libraries
• 🎯 Path-based Routing: Flexible route configuration

1. Install using Cargo:

cargo install harbr-router

2. Create a configuration file config.yml:

listen_addr: "0.0.0.0:8080"
global_timeout_ms: 5000
max_connections: 10000

routes:
  "/api":
    upstream: "http://backend-api:8080"
    health_check_path: "/health"
    timeout_ms: 3000
    retry_count: 2

3. Run the proxy:

harbr-router -c config.yml

Each route is defined by a path prefix and its configuration:

listen_addr: "0.0.0.0:8080"
global_timeout_ms: 5000
max_connections: 10000

routes:
  "/api":
    upstream: "http://backend-api:8080"
    health_check_path: "/health"
    timeout_ms: 3000
    retry_count: 2
  
  "/static":
    upstream: "http://static-server:80"
    timeout_ms: 1000
    retry_count: 1
  
  "/":
    upstream: "http://default-backend:8080"
    timeout_ms: 2000
    retry_count: 2

• Routes are matched by prefix
• More specific routes take precedence
• The "/" route acts as a catch-all default
• Health checks run on the specified path for each upstream

The proxy exposes Prometheus-compatible metrics at /metrics:

Health checks are performed on the specified health_check_path for each upstream:

• Method: GET
• Interval: 10 seconds
• Success: 200-299 status code
• Timeout: 5 seconds

Failed health checks will remove the upstream from the pool until it recovers.

FROM rust:1.70 as builder
WORKDIR /usr/src/harbr-router
COPY . .
RUN cargo build --release

FROM debian:bullseye-slim
COPY --from=builder /usr/src/harbr-router/target/release/harbr-router /usr/local/bin/
ENTRYPOINT ["harbr-router"]

version: '3'
services:
  proxy:
    image: harbr-router:latest
    ports:
      - "8080:8080"
    volumes:
      - ./config.yml:/etc/harbr-router/config.yml
    command: ["-c", "/etc/harbr-router/config.yml"]

apiVersion: v1
kind: ConfigMap
metadata:
  name: harbr-router-config
data:
  config.yml: |
    listen_addr: "0.0.0.0:8080"
    global_timeout_ms: 5000
    max_connections: 10000
    routes:
      "/api":
        upstream: "http://backend-api:8080"
        health_check_path: "/health"
        timeout_ms: 3000
        retry_count: 2

---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: harbr-router
spec:
  replicas: 3
  template:
    spec:
      containers:
      - name: harbr-router
        image: harbr-router:latest
        ports:
        - containerPort: 8080
        volumeMounts:
        - name: config
          mountPath: /etc/harbr-router
      volumes:
      - name: config
        configMap:
          name: harbr-router-config

For high-performance deployments, adjust system limits:

# /etc/sysctl.conf
net.core.somaxconn = 65535
net.ipv4.tcp_max_syn_backlog = 65535
net.ipv4.ip_local_port_range = 1024 65535
net.ipv4.tcp_tw_reuse = 1

Set these environment variables for optimal performance:

export RUST_MIN_THREADS=4
export RUST_MAX_THREADS=32

Contributions are welcome! Please read our Contributing Guide for details on our code of conduct and the process for submitting pull requests.

This project is licensed under the MIT License - see the LICENSE file for details.

Built with:

• Tokio - Async runtime
• Hyper - HTTP implementation
• Tower - Service abstractions
• Metrics - Metrics and monitoring