{"id":3893084,"url":"https://alion.io/job/s-i-systems-senior-backend-engineer-python-fastapi","title":"Senior Backend Engineer - Python / FastAPI","company":{"id":3865830,"name":"S.i. 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They're looking for an experienced Senior Backend Engineer to join the Supply Chain Technology team and contribute to the development of a new AI-powered supply chain platform.\n\nWorking alongside AI and Frontend Engineers, you will play a key role in designing, developing and implementing the backend services and APIs that power the platform.\n\nThis is an opportunity to contribute to a new technology initiative involving modern cloud-native architecture and AI-driven applications. We are looking for a strong Python developer with experience building scalable backend services, integrating databases and developing production-ready REST APIs.\n\nKey Responsibilities:\nDesign, develop and maintain scalable backend services and REST APIs using Python.\nBuild and integrate APIs using FastAPI, supporting the wider AI-powered supply chain platform.\nDevelop and maintain database integrations, ensuring reliable data access and efficient backend processing.\nCollaborate closely with AI Engineers to integrate backend services with LLM-powered applications and agentic AI workflows.\nWork alongside Frontend Engineers to support seamless API integrations and application functionality.\nDesign and implement scalable, reliable and maintainable backend architectures.\nDevelop and deploy applications within containerised environments using Docker and Kubernetes.\n\nMust Have Skills:\nStrong experience developing backend applications using Python, experience with FastAPI preferred.\nHands-on experience designing, developing, and integrating REST APIs.\nStrong database integration experience and understanding of data access patterns.\nExperience with Docker and Kubernetes for application containerisation and orchestration.\nExperience building and maintaining scalable, production-grade backend services.\nExperience with Google Cloud (GCP) preferred, open to AWS/Azure\n\nDisclaimer:\nAI may be used in evaluating candidates.\nThis posting is for an existing vacancy.","description_format":"text","description_chars":2144,"description_truncated":false,"requirements":{"experience_years_min":null,"management_years_min":null,"team_size_min":null,"manages_managers":false,"education":null,"security_clearance":false,"languages":[]},"benefits":[],"hiring_locations":[],"hiring_excludes":[],"relocation_offered":false,"industries":["Commerce"],"lifecycle":[{"event":"open","at":"2026-11-06T22:10:45Z"}],"visa":[],"liveness":{"score":52,"band":"ok","label":"Likely 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