Senior Data Scientist - AI Integration

About the role

Leyton CognitX, the AI and technology advisory arm of Leyton, brings together a team of over 200 tech experts and data scientists. It offers strategic advisory and custom development of AI solutions. As an experienced AI Software Engineer, you will join a multidisciplinary team (Data Scientists, DevOps, Consultants) and lead the architectural design, development and large-scale deployment of AI-based solutions for internal and external clients.

Key responsibilities

• Design, architect and develop complete, scalable features and platforms (APIs, business logic, databases, security)
• Implement complex AI systems in production: advanced RAG pipelines, LLM agent fleets, model fine-tuning and integration (OpenAI, Anthropic, open-source LLMs)
• Apply clean code practices (SOLID, Clean Architecture, design patterns) and run thorough code reviews
• Define the testing strategy (TDD, unit, integration, e2e, stress tests) for reliable deployments
• Deploy, monitor and optimize models and code in dedicated environments with robust CI/CD pipelines
• Act as a technical expert for clients, explain complex concepts and defend architectural decisions
• Mentor junior developers and DataLab interns

Required profile

• Engineering degree or Master's (Computer Science, Mathematics, Data Science) with 3 to 5 years of relevant experience
• Proven track record of designing, developing and deploying software integrating AI (ML, NLP or GenAI) with measurable business impact
• Ability to turn a vague business need into a solid technical architecture and finished product
• Strong communication skills to engage with demanding clients and to lead a technical team

Required skills

• System design, distributed systems and data structures and algorithms
• SOLID principles, microservices and event-driven architectures
• Docker, Kubernetes (a plus), GitHub Actions / GitLab CI, Terraform
• REST, gRPC, GraphQL; PostgreSQL, MongoDB, Redis, vector databases
• LLMOps: prompt engineering, token and cost management, streaming, model evaluation
• RAG and agents: LangChain, LlamaIndex, LangGraph, vector stores (FAISS, Pinecone, Qdrant, Milvus), Elasticsearch
• Tech stack appetite: Python, TypeScript / Node.js, Java / Spring, FastAPI / Django, React, AWS / GCP / Azure, Kafka / RabbitMQ

What we offer

• A central role on strategic projects for prestigious international clients
• Strong autonomy in technology and architecture decisions
• An environment of experts where you can learn and share knowledge
• An attractive compensation package tailored to expertise and experience
• A culture of excellence, continuous improvement and work-life balance