JobTitle: Senior Mechanical Engineer – Data CentresLocation: Dublin, Ireland (Hybrid)Reports to: Associate Mechanical Engineer / Mechanical DirectorCompany: ZeroOne DCAbout ZeroOne DCZeroOne DC is a specialist M&E engineering consultancy, founded by industry leaders with a combined track record of delivering over 2,000MW of data centre capacity across the EMEA region. We are a new, agile, and expert-led firm based in Dublin, and our mission is simple: to be the most trusted M&E partner in the European data centre industry by delivering exceptional, sustainable, and highly efficient design solutions.We operate on a "Core & Flex" model. Our Dublin-based "Core Team"—which you will be a part of—is a team of Dublin-based technical engineers and client-facing experts responsible for executing project deliverables, project leadership, technical quality assurance, and principal client relations. This team is supported by a scalable "Flex Team" of remote engineering professionals, allowing us to be incredibly agile and responsive.Our culture is built on Technical Excellence, Agility, Client Partnership, and a genuine "One Team Culture". We are not a large, bureaucratic firm; we are a focused team of experts poised for rapid growth, and this role is fundamental to our success.The OpportunityThis is a key role within our Dublin "Core Team," acting as a technical pillar for our mechanical design delivery. You will report to the Associate Engineer and work directly with the founding Mechanical Director, offering you unrivalled mentorship and a genuine influence on project direction.You will be a hands-on engineer, taking ownership of the design and delivery of complex cooling systems for a wide range of data centre projects. Our portfolio includes fast-paced data hall fit-outs, complex refurbishments, and large-scale new builds for colocation and hyperscale clients.This role is perfect for a technically-driven engineer who thrives on solving complex problems and wants to take a significant step in their career. You will not just be a number; you will be a foundational member of the team, helping to mentor our Intermediate and Graduate engineers and shaping the technical standards of a new, ambitious consultancy.Key ResponsibilitiesDesign & Delivery: Produce and lead the detailed design of mechanical systems, including HVAC, chilled water, CRAC/CRAH, ventilation, and other critical cooling solutions.Technical Production: Prepare and review technical spec ifications, calculations, schematics (P&IDs), and project reports.Quality Assurance: Act as a key reviewer, checking calculations, drawings, and reports produced by junior engineers and our remote "Flex Team" to ensure technical excellence.Project Management: Manage the day-to-day delivery of mechanical packages, coordinating resource and activities to ensure projects are delivered on time and to budget. You will report regularly to the Associate/Director on project performance.M&E Coordination: Work proactively with our electrical team to ensure a fully coordinated, clash-free, and efficient M&E design, upholding our "One Team Culture".Client & Contractor Liaison: Attend and actively participate in client, project, and site meetings, representing ZeroOne DC as a technical expert. You will also undertake site visits to monitor installation progress against the design spec ification.Mentorship: Provide technical guidance, training, and day-to-day coaching to our Intermediate and Graduate engineers, playing a key role in their professional development.The Ideal CandidateWe are looking for a proactive and detail-oriented engineer who is passionate about technical design and wants to make a real impact.Essential RequirementsExperience: years of experience in a mechanical engineering design role, ideally within a consultancy environment.Qualifications: Degree qualified (or equivalent) in Mechanical Engineering or Building Services Engineering.Technical Expertise: Proven technical competence in designing complex mechanical systems (HVAC, chilled water, etc.). Direct data centre experience is a significant advantage, but we will consider strong candidates from other high-tech, industrial, or critical environments.Chartership: Actively working towards or having already achieved Chartered Engineer (CEng) status with CIBSE, Engineers Ireland, or equivalent.Software Skills: Proficiency in AutoCAD and Revit, with a working knowledge of Bluebeam and mechanical design/calculation software.Standards: A strong understanding of CIBSE, ASHRAE, and relevant European (EN/IS) standards.Soft Skills: Excellent communication skills, a collaborative mindset, and the ability to manage your own workload and that of others in a fast-paced, agile environment.Desirable SkillsExperience working on projects across the EMEA region.Site-based experience, including witnessing commissioning.Familiarity with emerging cooling technologies and sustainability strategies.Why Join ZeroOne DC?Be a Pillar, Not a Cog: As a member of our "Core Team", your work and expertise will be visible and highly valued.Direct Mentorship: You will work directly with the founding Directors, who are some of the most experienced data centre engineers in the industry.Fast-Track Growth: This is a ground-floor opportunity. You will grow with the company as we execute our strategy, delivering projects for a wide range of colocation and hyperscale clients.True Flexibility: We are designed to be hybrid. This role follows our "2 days office, 3 days remote" model, offering a genuine work-life balance.Competitive Package: We offer a highly competitive salary, pension, and benefits package designed to attract and retain the best talent in the industry.