Backend API Engineer

About the Role We're looking for a senior Backend API Engineer with 8+ years of experience building and scaling production APIs, including at least 4 years working hands-on with FastAPI. You will design, build, and maintain high-performance, secure backend services, and act as a technical leader on architecture and system design decisions. Experience Requirements 8+ years of overall experience building and operating backend APIs in production environments Minimum 4 years of hands-on experience with FastAPI specifically (not just general Python API frameworks) Demonstrated experience owning services end-to-end — design, development, deployment, and monitoring Prior experience mentoring engineers or leading technical design discussions is a plus Required Skills (Mandatory) FastAPI: 4+ years of deep, hands-on production experience — routing, dependency injection, async endpoints, middleware, background tasks Pydantic: Strong command of data validation, serialization, custom validators, and schema design (v1/v2) Redis: Caching strategies, pub/sub, session/token storage, expiry and eviction policies Core Skills (Working Knowledge Expected) System Design — ability to architect scalable, fault-tolerant, high-throughput backend systems Authentication & Authorization — OAuth2, RBAC, secure API access patterns JWT — token issuance, validation, refresh flows, and security best practices HTTPX — async HTTP client usage for reliable service-to-service communication API Design — RESTful principles, versioning, rate limiting, backward compatibility Message Queues — experience with Kafka, RabbitMQ, SQS, or Celery for async processing L1 Cache Handling — in-memory/application-level caching alongside Redis (L2) for low-latency reads Exception Handling (RFC 9457) — standardized "Problem Details for HTTP APIs" error responses SQL — strong working knowledge of relational databases (PostgreSQL/MySQL), query optimization, and ORM usage (SQLAlchemy) Responsibilities Design and develop high-performance RESTful APIs using FastAPI with clean, validated schemas via Pydantic Architect scalable backend systems, making sound trade-offs on performance, reliability, and maintainability Implement multi-layer caching (Redis + in-memory L1 cache) to optimize latency and throughput Build secure authentication/authorization flows using JWT and OAuth2 Integrate with external and internal services using async HTTP clients (HTTPX) Design and consume message queues for asynchronous and event-driven processing Implement standardized, consistent error handling following RFC 9457 Write efficient, optimized SQL queries and review database interaction patterns Drive system design discussions and review architecture proposals across teams Write unit/integration tests and uphold high code quality and observability standards Nice to Have Experience with Docker, Kubernetes, and CI/CD pipelines Familiarity with observability tools (logging, tracing, metrics) Exposure to microservices architecture at scale