Prompt Engineer

Prompt Engineer

As a Prompt Engineer at La Banque Postale, you will contribute to the design, optimization, and governance of prompts. You will be involved in the entire lifecycle of prompts: design, testing, evaluation, quality assurance, deployment, documentation, and continuous improvement.

Within the Operational Performance, Payments, and Digital Department (DPOPN) of La Banque Postale and Assurance (2000 employees across Nantes, Toulouse, Issy-Les-Moulineaux, Gradignan) and the Innovation, Digital, and Data Department, your actions will have a positive impact on our clients, promoting more responsible finance and a just transition.

Your Missions

• Conception & optimization of prompts: Construct, refine, and maintain high-performing prompts (system, instruction, few-shot...). Create advanced prompting strategies (chain-of-thought, multi-turn, routing...). Build and maintain a repository of standardized, high-performing prompts for banking use cases.
• Integration into product: Participate in the development of assistants with Data & IT teams. Manage prompt versioning and tracking over time. Support and challenge business teams in identifying their needs to develop high-value use cases.
• Evaluation & quality: Implement testing protocols: benchmarks, quality assessment (hallucinations, security, banking accuracy). Deploy A/B tests and semi-supervised automatic evaluation tools. Continuously measure and improve conversational quality.
• Compliance, security & governance: Ensure regulatory compliance (banking, GDPR, IA Act). Draft and disseminate prompt guidelines for business teams.
• Documentation & evangelization: Write documentation, playbooks, and best practices. Train business teams on prompt usage and creation, and on new AI paradigms. Contribute to the diffusion of AI culture within the Data & IA Factory.

Technical Environment

NLP, Generative AI, Mistral and Enterprise Chat (open-weight, finetuning, guardrails), LLM, Git, CI/CD, LLM monitoring, Python.

Your Team

Within this Data and Artificial Intelligence Department (DDIA), you will join the Data Valorization department, Data & IA Factory. This is a team of 7 people, comprising a manager, 1 Product Manager, 1 project manager, and 4 data scientists. You will collaborate closely with Data Sciences, IT, and business teams to integrate robust, secure, and auditable conversational experiences.

Why You?

With an Engineering degree or equivalent, you have significant experience in NLP or Generative AI or in Data product development with expertise in prompt engineering (advanced techniques, optimization, banking constraints). Ideally familiar with the banking environment, your interpersonal skills and adaptability make you a true coordinator capable of working cross-functionally with stakeholders at various levels of Data literacy.

La Banque Postale is a committed company, promoting diversity and equal opportunities, ensuring access to all its professions without discrimination based on gender, social or cultural origin, sexual orientation, or disability. Join us and let's build the preferred bank of the French together.

You have no idea what we can achieve together. Did you know that at La Banque Postale, we have a unique perspective on our profession? Our youth makes us a bank with convictions and ambitions, one that truly believes that finance has meaning and plays a real societal role. We support over a million financially vulnerable clients and are the world's leading bank in CSR due to our actions for sustainable finance. Our youth also makes us ambitious. Rightly so! Our Banking/Insurance Group serves over 20 million clients, making us the third-largest group in the sector in France. We are brimming with innovative ideas and projects to continue our development, always with the same commitment to our employees: offering them every opportunity to be amazed.

Key skills/competency

• Prompt Engineering
• NLP
• Generative AI
• LLM
• Python
• Data Science
• Product Development
• AI Governance
• Machine Learning
• Banking