AI engineer (AI & GenAI) - People Domain (f/m/d)

As part of an open-ended permanent position, we are recruiting an **AI engineer (f/m/d)**, based in Paris.

🚀 CONTEXT & STRATEGIC CHALLENGES

Within Decathlon Digital, the People Data team is launching a major initiative: to transform the experience of our 100,000 employees by integrating Generative and Agentic AI.

Faced with the fragmentation of the HR ecosystem in over 70 countries, our ambition is to build a simplification layer by leveraging the new solutions offered by AI. This is a centralized and tool-agnostic intelligence layer, capable of interacting with our entire infrastructure (Workday, Data Lake, University, ...) to evolve our interfaces from a consultation logic to an action logic.

In this context, we are developing DaiLY, our HR conversational agent. It helps our employees and managers to instantly access reliable information, sourced from our Workday documentation and our People policies.

Already successfully deployed in France, DaiLY is entering a new scaling phase: international expansion, industrialization of evaluations, continuous improvement of our models and their quality, and deployment and integration of autonomous HR agents.

To lead this project, we are not just looking for a developer, we need a "Builder": someone capable of translating a business need into a technical solution, implementing it, qualifying it, deploying it, and maintaining it over time.

🎯 YOUR MISSION

We are looking for an experienced **AI Engineer** to actively participate in the industrialization and development of DaiLY. Your objective is clear: to transform HR business needs into reliable, measurable, and robust AI functionalities.

To meet this challenge, you will work within a **dedicated team**, in direct collaboration with other AI Engineers, a Lead AI Engineer (who will guide global architecture choices), and a Product Manager. This close-knit organization will allow you to ensure perfect synergy between product challenges, the roadmap, and technical implementation.

You will have a key role in the evolution of DaiLY: moving from a simple consultation model (Q&A) to a **true transactional agent system** capable of triggering concrete actions (e.g., requesting leave in Workday, registering for training via Decathlon University).

🛠 YOUR RESPONSIBILITIES

1. Agentic Development & Functionalities

• Participate in extending DaiLY's capabilities to write actions by implementing tool-calling protocols (MCP - Model Context Protocol) and inter-agent communications (A2A).
• Implement advanced chunking and re-ranking strategies to prioritize specific HR domain rules.
• Contribute to optimizing costs, latency, and overall system efficiency in conjunction with the Platform and Infrastructure teams.

1. Quality, Evaluation & Observability (LLMOps)

• Develop and maintain the quality layer of the multi-agent RAG pipeline (Vertex AI Search / Discovery Engine).
• Ensure the grounding of responses and verification of citations to guarantee traceability to a source of truth.
• Set up robust observability pipelines for online and offline evaluation (OpenTelemetry, MLflow).
• Code automatic evaluators based on golden datasets to iterate with confidence and prevent regressions before each production deployment.
• Integrate guardrails to protect the system and users against hallucinations and errors.

1. Security, Isolation & International Deployment

• Access Management (ACLs): Implement granular and dynamic access rights management at the indexing and retrieval level, ensuring that an employee strictly only accesses HR documents within their scope.
• Isolation & Multi-tenancy: Implement metadata filtering strategies in the vector database and isolation (of indexes and/or models) to ensure perfect data separation between Decathlon's various fiscal companies, legal entities, and geographies.
• Multilingual Support: Contribute to the internationalization architecture of DaiLY by adapting RAG pipelines, embedding, and inference to maintain a high level of performance and relevance across a wide diversity of languages.

1. Product & Business Impact

• Assist in analyzing user intentions to measure DaiLY's impact.
• Translate, with the support of the Product Manager and Lead, business challenges into model behaviors and success metrics.

🧠 PROFILE WANTED

We are looking for a profile with at least initial experience.

• Experience: Experienced profile with three years of professional experience in a company (excluding internships and work-study programs) in AI Engineering, ML Engineering, or AI-oriented Software Engineering. You also have at least one concrete and successful experience in deploying a GenAI or agentic system into production.
• Technical Stack: Solid command of Python, the GCP / Vertex AI ecosystem, and orchestration frameworks (LangChain, LlamaIndex, or ADK).
• LLM & Agentic Expertise: Solid command of RAG architectures (vector search, Vertex AI Vector Search, advanced metadata management), but especially agentic technical concepts: function/tool-calling, reasoning loops (ReAct, etc.), multi-agent workflow orchestration, structured output, and context/memory management.
• Quality & Evaluation: Ability to diagnose an incorrect response (model, retrieval, or data problem) and an aptitude for application observability (SQL / BigQuery / MLflow).
• Languages: Fluent French mandatory & fluent professional English (international environment).

The pluses:

• In-depth technical knowledge of A2A (Agent-to-Agent) and MCP protocols.
• Experience in multimodal document processing or in HRIS ecosystems (e.g., Workday).
• Technical understanding of security issues (RBAC, ACLs, GDPR) applied to LLMs.
• Knowledge of microservices architectures and API design.

🎁 WHAT WE OFFER

• The opportunity to develop a cutting-edge agentic AI product with a direct impact on the daily lives of 100,000 employees.
• A premium technological environment (Google Cloud Stack / Vertex AI / Databricks).
• A flexible remote work policy (2 days per week remote, the rest in our Paris offices - Canal de l’Ourcq).
• A delivery culture focused on autonomy, collective intelligence, and skill development (support from a Lead, certifications, training).
• Attractive benefits (monthly/quarterly bonuses, employee share ownership).
• An atmosphere resolutely focused on sports (numerous corporate events, product tests, sports or non-sports lunch breaks, ...).