Senior AI / LLM Backend Engineer (Python)

Company Description

Publicis Sapient is a digital transformation partner helping established organizations get to their future, digitally enabled state, both in the way they work and the way they serve their customers. We help unlock value through a start-up mindset and modern methods, fusing strategy, consulting, and customer experience with agile engineering and problem-solving creativity. United by our core values and our purpose of helping people thrive in the brave pursuit of next, our 20,000+ people in 53 offices around the world combine experience across technology, data sciences, consulting, and customer obsession to accelerate our clients’ businesses through designing the products and services their customers truly value.

Responsibilities

As a Senior AI / LLM Backend Engineer, you will design, build, and scale production-grade Generative AI systems that power enterprise products and platforms. You’ll work hands-on with Python, LLMs, and cloud-native architectures to deliver reliable, scalable, and cost-efficient AI solutions—moving beyond prototypes into real-world impact. This role sits at the intersection of backend engineering, applied machine learning, and cloud architecture, partnering closely with product, platform, and data teams.

Your Impact

• Design and build end-to-end LLM-powered systems, including RAG pipelines and agent-based workflows.
• Develop and maintain Python-based backend services exposing AI capabilities via REST APIs.
• Implement vector search and retrieval layers using tools such as FAISS, Milvus, or similar.
• Architect scalable systems using caching layers (Redis or equivalent) and durable databases.
• Integrate LLM workflows using orchestration frameworks (e.g., LangChain, LangGraph).
• Ensure production readiness through CI/CD pipelines, testing, monitoring, and performance optimization.
• Collaborate with cross-functional teams to translate business problems into robust AI-driven solutions.

Qualifications

Skills & Experience

• Strong software engineering background with extensive experience in Python.
• Hands-on experience building LLM-based applications, including RAG architectures.
• Solid understanding of backend systems, APIs, and distributed architectures.
• Experience with vector databases or indexes (FAISS, Milvus, or equivalents).
• Familiarity with caching systems (Redis or similar) and persistent data stores.
• Experience designing and consuming RESTful APIs.
• Proven experience with CI/CD pipelines and production deployment workflows.
• Hands-on experience deploying systems on cloud platforms (AWS, GCP, or Azure).

Set Yourself Apart With

• Experience with LangChain, LangGraph, or similar LLM orchestration frameworks.
• Knowledge of agent-based systems and multi-step reasoning workflows.
• Experience operating AI systems at scale, including cost, latency, and reliability optimization.
• Familiarity with containerization and cloud-native tooling (Docker, Kubernetes).
• Exposure to MLOps / LLMOps practices in real production environments.
• Contributions to internal platforms, shared tooling, or open-source projects.

Why Publicis Sapient

We build enterprise-grade AI products, not experiments. You’ll work on systems that operate at scale, integrate deeply into complex platforms, and deliver measurable business outcomes—combining strong engineering practices with applied AI innovation.

 

Additional Information

• An inclusive workplace that promotes diversity and collaboration.
• Access to ongoing learning and development opportunities.
• Competitive compensation and benefits package.
• Flexibility to support work-life balance.
• Comprehensive health benefits for you and your family.
• Generous paid leave and holidays.
• Wellness program and employee assistance.

As part of our dedication to an inclusive and diverse workforce, Publicis Sapient is committed to Equal Employment Opportunity without regard for race, color, national origin, ethnicity, gender, protected veteran status, disability, sexual orientation, gender identity, or religion. We are also committed to providing reasonable accommodations for qualified individuals with disabilities and disabled veterans in our job application procedures. If you need assistance or an accommodation due to a disability, you may contact us at [email protected]