Python Product Engineer

At Formel AI, we combine the creativity of generative AI with the reliability of mathematical formal methods. By leveraging the verification capabilities of formal methods, such as the Lean 4, we pioneer a new generation of Large Language Models (LLMs) that are reliable, transparent, and cost-efficient. We're honored to have received the 2nd spot of the Innovation Prize from École normale supérieure in Nov 2025.

Formel AI is founded by Sylvain Combettes (CEO) and Antoine Mazarguil (CTO), who met during their PhDs at ENS Paris-Saclay. We closed an oversubscribed angel round in Feb 2026, backed by 30+ top-tier business angels including the founders of Datadog, Dataiku, Nabla, and Artefact. Our scientific advisory board includes Full Professors from Ecole polytechnique, ENS Paris-Saclay, and Ecole des Ponts.

We're now onboarding our first design partners and building the team to make it happen. Come join us!