Microservices API Gateway

The Challenge

As our microservices architecture grew, we faced issues with service discovery, centralized authentication, and rate limiting. Developers were re-implementing auth logic in every service, leading to security inconsistencies and code bloat.

The Solution: A Centralized Gateway

I designed a custom API Gateway to act as the single entry point for all external traffic.

Core Architecture

• Language: Built with Go (Golang) for its high concurrency performance and low memory footprint.
• Reverse Proxy: Implemented a custom reverse proxy that handles request routing, load balancing, and SSL termination.

Key Features Implemented

1. Centralized Authentication (JWT)

   • The gateway leverages a separate Auth Service to validate JWTs.
   • It injects user context headers into downstream requests, simplifying backend services.

2. Rate Limiting & Throttling

   • Implemented the Token Bucket algorithm using Redis to prevent abuse and ensure fair usage across API consumers.
   • Configurable limits per user role or API key.

3. Circuit Breaking

   • Integrated a circuit breaker pattern to detect failing downstream services.
   • Prevents cascading failures by failing fast and allowing the system to recover gracefully.

Results

• Performance: Capable of handling 10,000+ RPS with less than 20ms added latency.
• Reliability: System uptime improved from 99.5% to 99.99% due to better failure isolation.
• Developer Experience: Removed 90% of boilerplate code from individual microservices, allowing teams to focus on business logic.

This project demonstrates my strong grasp of backend engineering principles, distributed systems, and infrastructure-as-code.