Backend Engineer _ AI Gateway- Bilingual (Korean/ English)

For More Open Positions Visit us at:

http://recruiting.woongjininc.com/

Our Mission

WOONGJIN INC. is a rapidly growing team who provides a range of unique, exceptional, and enhanced services to our clients. We have a strong moral code that includes the service of goodness without expectations of reward. We are motivated by the sense of responsibility and servant leadership.

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.

What we are looking for

• 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 canary/blue-green deployments.

• Enterprise Security Gateways - Integration with CASB/DLP/WSS or similar edge-security platforms; centralized logging & audit trails.
• IAM & SSO - Configuring Azure AD/Entra ID, Okta, SAML 2.0 or OIDC SSO flows; managing Conditional Access & SCIM provisioning.
• AI/LLM Pipelines - Building prompt-engineering workflows, PII anonymisation, and monitoring Azure OpenAI (or comparable) usage, rate limits & cost.
• API-Gateway Operations - Custom webhook/REST integrations, circuit-breaker patterns, rate-limiting, auto-retry and health-checking.
• Observability & FinOps - End-to-end monitoring with Datadog, Prometheus/Grafana or Azure Monitor; proactive cost-optimisation and 24/7 incident response (SLA/SLO).
• Bilingual Korean Highly Prefer

All your information will be kept confidential according to EEO guidelines.

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