Senior AI Engineer

• Location: Paris, Châtelet – Hybrid (2 days on-site / 3 days remote)

• Contract: Full-time (permanent)

• Team: Technology

• Compensation: €75,000–€90,000 gross annual base + BSPCE (equity), depending on level

🚀 About Mendo — and why this matters

We're living through the biggest technological shift since the internet. Generative AI is changing how people work — yet most teams barely scratch the surface, unsure how to turn the hype into real, everyday value. Closing that gap is exactly what Mendo does.

Mendo is the AI Transformation Platform for enterprise clients. Rather than adding yet another tool to the stack, we work right inside the AI tools teams already use — Microsoft 365 Copilot, ChatGPT, Gemini, Claude, and internal agents. From there, we guide people toward proven use cases, certify their skills, and give organizations a clear view of what's actually driving value.

And it's working. We support 100+ enterprise clients — including EY, PwC, Crédit Agricole, SNCF, La Poste, ENGIE, Groupe SEB, and Novo Nordisk — with 200+ use cases live, a user NPS of 64, and 3x GenAI ROI within months. We've raised €12M following our Series A and we're scaling fast.

Join us and you won't just ship software — you'll shape how leading organizations adopt the defining technology of our era, and help keep people at the center of the AI revolution rather than left behind by it. We believe humans have a vital role to play in this revolution, and we're building the platform that keeps them there.

🧭 Core mission

Own AI at Mendo. As our first dedicated AI Engineer, you'll be responsible for both the AI research and the AI features we ship across the whole company — from the proprietary language models we package into our adoption product and run on people's devices, to the analytics and AI strategy recommendations we surface in our impact product.

You'll work transverse across every product and squad, set our AI direction, and stay deeply hands-on. There are no direct reports to begin with — we need someone highly operational who ships — but you'll lay the foundations for an AI team that grows next year, and you'll be the natural person to lead it.

🛠️ Key responsibilities

1. Own AI research and features end to end

• Drive applied AI research and turn it into features that ship across our products.

• Train, fine-tune, and evaluate our proprietary language models — including small models that run on-device.

• Define the AI roadmap and arbitrate AI decisions across product, engineering, and sales.

2. Ship pragmatically, measure rigorously

• Build evaluation harnesses (golden sets, regression tests) so AI features don't silently regress.

• Optimise relentlessly for cost, latency, and quality — ship real value, not demo-ware.

• Have the judgement to kill projects that won't deliver user impact.

3. Power analytics and AI recommendations

• Build the AI behind our usage analytics and the AI strategy recommendations we give clients.

• Turn real usage data into insights that help organizations adopt AI with confidence.

4. Build the AI practice

• Set the bar for AI craft, evaluation rigor, and pragmatism across the company.

• Create the playbooks and tooling that let an AI team grow on solid foundations next year.

• Mentor engineers and contribute to hiring as we scale.

🧱 Tech stack

• Languages: Python for AI/ML work, TypeScript across the product.

• On-device / SLMs: GGUF models running in-browser via WebLLM and wllama (llama.cpp compiled to WASM), packaged into our browser and desktop connectors.

• LLMs & GenAI: OpenAI APIs, retrieval-augmented generation, and embeddings, integrated into Microsoft 365 Copilot, ChatGPT, Gemini, Claude, and internal agents.

• ML tooling: sentence-transformers, HuggingFace Transformers, scikit-learn, and TensorFlow, served through a Python service.

• Data: MongoDB and Redis.

• Infra & deployment: Azure / AKS with Helm, Docker containers, GitHub Actions CI/CD.

• AI-augmented engineering: Claude Code / Cursor, MCP tooling, and internal AI agents are part of the daily workflow — not a bonus.

This stack is always evolving, and we're counting on you to help us evolve and improve it.

🧩 Required skills

Experience & expertise

• 6+ years in ML / AI engineering, with a track record of shipping models and AI features to production.

• Strong command of LLM fine-tuning, RAG, embeddings, and evaluation (golden sets, LLM-as-judge, regression tests).

• Experience optimising AI systems for cost, latency, and quality in production.

• Solid software engineering fundamentals — you ship and operate, not just prototype.

• Comfortable in Python and able to work across a TypeScript product codebase.

• Experience with small language models (SLMs) and on-device / on-prem model deployment is a strong plus.

Ways of working

• Ruthless pragmatism and a product-first mindset — user impact over technical novelty.

• Able to frame ambiguous AI problems and decide what's actually worth shipping.

• Clear communicator of AI trade-offs to non-technical stakeholders.

• Excellent command of French and English, both technical and professional.

Mindset

• Natural rigor and a feel for evaluation-driven development.

• Genuine curiosity for a fast-moving AI landscape — without chasing hype.

• Eager to grow into leading an AI team.

• Strong team spirit, autonomy, and a sense of priorities in a fast-moving scale-up.

• Alignment with our values: Learning, Innovation, Excellence, Kindness, Transparency.

📈 What we offer

• Competitive package: €80,000–€95,000 base depending on level, plus BSPCE (equity) under our Series A policy.

• Own AI at Mendo: as our first dedicated AI Engineer, you'll define our AI direction and build the practice from the ground up.

• Real impact: your models and features ship to 100+ enterprise clients.

• Room to grow: build and lead an AI team as we scale next year.

• A learning environment: a team passionate about new technologies and generative AI.

• A stimulating workplace: a young, supportive culture where everyone helps each other.

• Flexibility: a hybrid 2-day/3-day remote model.

• Meaningful mission: helping make AI accessible and impactful for everyone.