Python / FastAPI Backend Engineer – API Migration

Role - Python / FastAPI Backend Engineer – API Migration Experience :- 6–12 years Role Overview We are looking for experienced Python Backend Engineers to work on an API migration initiative. The role involves migrating existing REST APIs from a Nuclio/Iguazio serverless environment to Python + FastAPI microservices running on Kubernetes , while maintaining functional and API contract parity with the existing services. The engineer will work closely with the technical lead, QA, client SMEs, and platform teams to understand existing implementations, migrate business logic, integrate with existing backend systems, and validate the migrated services. Key Responsibilities Analyze existing Nuclio-based REST APIs, handlers, business logic, and dependencies. Migrate API business logic to Python/FastAPI microservices. Maintain functional and API contract parity with existing services. Work with existing shared libraries/SDKs and FastAPI frameworks. Integrate APIs with backend systems and data stores. Implement request validation, error handling, authentication/entitlement logic, and API transformations. Develop unit and integration tests for migrated services. Perform API contract and functional validation against existing services. Troubleshoot application, integration, and performance issues. Participate in code reviews, technical discussions, and design reviews. Prepare API/OpenAPI documentation and operational handover documentation. Follow established coding, CI/CD, security, and development standards. Required Technical Skills Must Have Strong experience in Python backend development . Hands-on experience with FastAPI or similar Python REST frameworks. Strong understanding of REST APIs, API contracts, JSON/XML, HTTP methods, and status codes . Experience developing microservices and migrating/refactoring existing applications. Strong understanding of unit and integration testing using frameworks such as PyTest . Experience working with one or more databases such as: MongoDB Cassandra Elasticsearch / Solr SQL/NoSQL databases Experience with asynchronous programming/concurrency in Python. Good understanding of Docker and Kubernetes environments. Experience with Git-based development and CI/CD pipelines. Strong debugging and problem-solving skills. Good to Have Experience with Nuclio, Iguazio, V3IO, or other serverless platforms . Experience working with Kafka/event-driven architectures . Experience with NFS/HDFS/S3 or distributed file systems. Experience with API gateways such as Kong . Experience with authentication, authorization, RBAC, or entitlement frameworks. Experience with performance testing and API benchmarking. Experience with observability, logging, metrics, and distributed tracing. Experience working with OpenAPI/Swagger . Exposure to AI-assisted software development and code migration tools.