Founding AI Engineer @Plato (backed by Hexa)

Job description

### **⚖️ Who are we** **Plato is building the AI OS for litigation lawyers.** With AI, the legal industry is on the verge of a major transformation. Litigation lawyers are overwhelmed by complex and repetitive tasks: complex damage calculations, thousands of documents to review, days spent drafting legal documents, and more. **Our mission:** Build the leading **AI OS for litigation lawyers**, enabling professionals to work **5x faster**, by putting their whole firm on autopilot. Plato already supports more than 30 law firms and 1 major insurance company’s legal team, who use our solution daily to manage hundreds of active cases. Founded in January 2026 by [Ben](https://www.linkedin.com/in/ben-lasseri/) (CEO) and [Alexandre](https://www.linkedin.com/in/alexandredeboutray/) (CTO), we are backed by Hexa (formerly eFounders), Europe’s leading startup studio. Hexa has launched over 35 companies, including unicorns such as Front, Aircall, and Spendesk, collectively generating more than €230M in ARR and raising over €750M in funding. Plato is live with real users, real data and real revenue, solving concrete legal workflows in production. We’re now looking for a Founding AI Engineer to help us turn the latest advances in AI into reliable products used every day by legal professionals. ### **🎯 Your mission** You’ll work directly with [Alexandre](https://www.linkedin.com/in/alexandredeboutray/?locale=fr_FR) , our CTO, at the intersection of **AI, software engineering and product**. Your job is not to do AI research for the sake of research. You’ll experiment with models and approaches, understand what works, and turn the best solutions into **reliable production systems**. You'll work on problems such as building agentic workflows, making sense complex legal documents, designing autonomous long-running agents, and improving the quality and reliability of AI-generated outputs. **Responsibilities** **Build AI-powered product features** - Design and ship AI features used directly by lawyers - Be at the bleeing edge of the agentic stack: memory, sandboxes, code mode, lots of tools, subagents… - Turn prototypes and experiments into production-ready feature **Work with complex data** - Extract, structure and reason over large volumes of unstructured legal documents - Build robust data and document-processing pipelines - Experiment with different models and approaches to improve accuracy and reliability **Make AI work in production** - Evaluate and improve agent outcomes through testing, evals and iteration - Optimize systems for quality, latency and cost - Build the backend services and infrastructure needed to run AI reliably at scale **Shape the product** - Work directly with the founders and users to understand real-world problems - Move quickly from problem → experiment → production (think days, not weeks) - Take ownership of your projects from exploration to deployment ### **🤩 This role is for you if** We're looking for a **strong software or AI engineer with 2+ years of experience** who wants to build real-world AI products at the forefront of the agentic stack. You like working close to founders and users, making pragmatic technical decisions, and shipping software that actually runs in production. **You’ll thrive in this role if you:** - Have a strong **software engineering foundation**, ideally with Typescript and experience shipping production systems - Have experience with **agents and/or evals** and frameworks like Mastra, Eve, Pydantic, Langchain, etc… - Can take an AI problem from **experimentation to production** - Enjoy **solving problems** with no clear solution - Have a strong **product mindset** and care about user impact - Are **autonomous and pragmatic**, comfortable navigating early-stage ambiguity and shipping fast ### **⚙️ Our tech stack** Our stack is designed to support **AI-first workflows** and **production reliability**. - **Backend & Frontend:** TypeScript, Node.js, React, tRPC - **Infrastructure:** AWS (Terraform) - **Data & AI:** Mastra, Bedrock - **Database:** Postgres *You don't need to master every tool — what matters is your ability to design robust systems, learn fast, and make sound technical trade-offs.* ### **💎 What we offer** - **Build alongside a strong AI expert:** Work closely with [Alexandre](https://www.linkedin.com/in/alexandredeboutray/), our CTO, who has deep expertise in AI agents, and turn cutting-edge AI into production systems. - **Ownership & Impact:** As the second engineering hire, you'll have real influence on the product and technical direction - **Bring AI to real users:** Build production AI systems that solve real problems in a complex, high-stakes domain - **Hexa ecosystem:** Access to expertise, resources, and network from one of Europe's leading startup studios - **Competitive package:** Attractive salary + meaningful equity - **Paris-based team:** Work alongside the founding team in our office - **Growth:** Opportunity to grow into a technical leadership role as the team scales *Plato is committed to creating a diverse environment. All qualified applicants will receive consideration for employment irrespective of gender, origin, identity, background and sexual orientation.* *We know there's a long way to go regarding diversity in our industry, which is why we encourage all applicants to apply to our open positions.*