Sea Trials Engineer

À propos de nous Computing is hungry for electricity. AI and the cloud consume it faster than land-based grids can supply it. On land, data centres are hitting three walls: available power, freshwater and land. CIRCEO chose to head offshore. Founded in Nantes in 2025, the company designs autonomous energy ships: hulls carrying wind turbines that harvest the open-ocean wind, stronger and steadier than on land, and power on-board servers cooled directly by seawater. No grid connection, no freshwater draw, no land take. Behind the project are three founders with a proven track record: Fabien Bardinet (former COO of Aldebaran Robotics, former CEO of Balyo, former VP at Airbus), Boris Morinière (CEA, Airbus) and Michel Soubrier (twenty years at Naval Group, from nuclear submarines to shipyard production). The roadmap is concrete: a demonstrator, a 16-metre trimaran, with construction starting in late 2026 and launch in 2027, then an 80-metre ship, currently in preliminary design, the first of a fleet built for series production. CIRCEO is now hiring its first team: the people who will commit everything to opening a territory no one has explored yet. Around twenty people, each working directly with the founders, each owning their system end to end. The culture taking shape fits in a few words: enthusiasm, shared intelligence and a diverse team, drawn from energy, naval, computing and beyond. Stimulating, brilliant people, maybe a little crazy in places, and genuinely electrifying when they come together around the same problem. Here, we ship machines, not slide decks, and the sea has the final say: every assumption will be measured there. Want to see more? Dive into the project at and explore every open position on the Careers page: To take its first ship to sea, CIRCEO is hiring its: Sea Trials Engineer New position – Permanent contract (CDI), based in Nantes, France Mission Reporting to Michel Soubrier, COO, you are the person who will take the demonstrator to sea and bring back results no one can dispute. For this role, CIRCEO is looking for a sailor first. 1. Prepare ashore You orchestrate the pre-integration and validation of systems in the integration hall. You plan the trials as equipment arrives, and you know how testing at sea works: what to measure, in what order, and in what conditions. 2. Take the helm of the trials Once the trimaran is afloat, you lead the trials campaign and the ship's operational life, maintenance included, and you sail the boat. You read the weather, the sea and the crew's fatigue. You make the go / no-go calls, with calm authority in the face of technical impatience. 3. Guarantee rigour You ensure the traceability of every trial and configuration management. You are the point of contact for the maritime authorities and the guarantor of the trials' regulatory framework. Profil You have sailed, a lot, and with responsibility. Offshore racing, high-level regattas, a racing multihull test team or the merchant navy: your sailing background is the foundation of this role. It comes with an engineering degree or an equivalent technical path, and around ten years of experience.

• Your seamanship is your first asset. No specific licence is required, and skippering very large vessels is not necessary. Having sailed in charge of a boat, for at least six months, is.
• You know how a sea trial is prepared and run : protocol, measurement, safety and lessons learned.
• Your authority is calm. You know how to say no when the sea demands it, and explain it to a team eager to see its systems running.
• Traceability is second nature. For you, an undocumented trial never happened.
• You build on proven foundations rather than intuition. AI (Claude, Gemini or another) is already one of your tools, to prepare a protocol, analyse data or multiply your thinking.
• English is the team's working language. You speak it fluently, including in fast-paced spoken exchanges.

Above all, and this is the founders' first criterion, you are passionate. About the sea, of course, but not only. Curious in life as in your work, you like to understand how the machines you sail actually work, and you look for the solution before flagging the problem. Joining CIRCEO means taking to sea a boat no one has ever tested, and bringing back the evidence that will open the way for an entire fleet. It means living an industrial adventure without leaving the deck. Do you recognise yourself in this description, and are you determined there will never be smoke on the water? Then apply under the reference #SmokeOnTheWater Salary and benefits · Salary: shaped around your background and what you bring to the founding team. We discuss it openly from our very first conversation. Process and inclusion

• 1/ With L'Etincelle RH: a phone call + an interview (supported by tools and tests to understand you more finely)
• 2/ With CIRCEO: meetings with at least two of the three founders, Fabien Bardinet (CEO), Boris Morinière (CTO) and Michel Soubrier (COO), plus a technical case study

Interviews can be held in English or French. The position opens in the first quarter of 2027, to prepare the demonstrator's launch, with a start as soon as possible. If you have a notice period, let's talk, we can work with it. Gender diversity is a deliberate goal at CIRCEO: applications from women sailors and engineers are particularly welcome. L'Etincelle RH stands for companies open to diversity and difference. Non-discrimination is second nature to us: you can count on our objectivity.