Neural API Gateway
A high-throughput API gateway with intelligent rate limiting, semantic request routing, and real-time anomaly detection built on a Rust core with Python ML inference workers.
Overview
The Neural API Gateway handles 2M+ requests per day for a SaaS platform serving enterprise clients. It combines a blazing-fast Rust core with Python ML workers to deliver intelligent traffic management that goes beyond traditional rule-based systems.
Architecture
Rust Core
The hot path — request parsing, header manipulation, connection pooling — runs entirely in Rust using the Tokio async runtime. This gives us sub-millisecond overhead per request.
ML Inference Layer
A fleet of Python workers (FastAPI + PyTorch) handle the AI features:
- Anomaly detection — flags unusual traffic patterns in real time
- Semantic routing — routes requests to the optimal backend based on payload semantics
- Predictive rate limiting — adjusts limits based on predicted client behavior
Redis Cluster
All shared state (rate limit counters, circuit breaker state, session data) lives in a Redis cluster with 3 replicas for high availability.
Performance
| Metric | Before | After |
|---|---|---|
| P99 latency | 45ms | 3.2ms |
| Throughput | 80k req/s | 340k req/s |
| False positive blocks | 12% | 0.8% |
Key Challenge: Zero-Downtime Deploys
Rolling updates to a stateful gateway are tricky. We solved this with a blue-green deployment strategy backed by Kubernetes, where we gradually shift traffic using weighted routing rules in Nginx Ingress.