Backend Engineer_AI Gateway

1 yr Contract Full-Time, On Site Relocation Required (Englewood Cliffs, NJ until 9/2026, Plano, TX effective 10/2026) Pay Rate: ~$10,570/mo DOE We are building an AI Gateway — a high-performance, secure intermediary layer that routes, inspects, and governs all traffic between enterprise clients and LLM/AI service providers. This role requires deep expertise in network programming, async Python, and cloud infrastructure to design and operate a latency-sensitive, policy-driven gateway that handles massive concurrent streaming connections at scale. Async Python & Network Programming (3 + yrs) – Strong hands‑on experience with asyncio, aiohttp/anyio, low‑level TCP/UDP sockets, WebSocket & SSE servers, TLS handshake, connection‑pooling, keep‑alive, and zero‑copy buffering. Streaming & Large‑Payload Handling – Ability to manage chunked transfer, bidirectional streaming, back‑pressure and high‑throughput data paths for real‑time LLM inference. Protocol Knowledge – Working familiarity with HTTP/2 & HTTP/3 (multiplexing, HPACK), gRPC, and occasional custom protocol parsers. FastAPI‑Based Backend (3 + yrs) – Design, develop and test production‑grade REST/Streaming APIs; pragmatic use of Pydantic, dependency injection and OpenAPI docs. Containerization & Kubernetes – Docker, AKS/EKS/GKE deployment experience; HPA/VPA scaling, rolling updates, and service‑mesh (e.g., Istio/Envoy) basics. Async Messaging & Event‑Driven Design – Production use of Redis Streams, RabbitMQ or Kafka for decoupled task queues, retries and back‑off logic. PostgreSQL & Vault – Advanced query tuning, partitioning, PgBouncer pooling, plus HashiCorp Vault (dynamic secrets, transit encryption) for key management. Cloud Networking & Security – L4/L7 load balancing, TLS termination, reverse‑proxy (NGINX/Envoy), mTLS between services, and automated cert lifecycle (ACME/Let’s Encrypt). IaC & CI/CD – Terraform modules for multi‑env infra, plus GitHub Actions/GitLab CI pipelines with container image scanning and