Lead Mechanical Design Engineer

CSMC is shaping the future of advanced energy and aerospace technologies through innovation in nuclear microreactors, quantum sensing, and deep-tech engineering. We’re looking for a Mechanical Engineer to join our growing team and help us design and integrate micro-modular reactors (MMRs) and their supporting subsystems for both space and terrestrial applications. About the Role The Lead Mechanical Design Engineer will be responsible for detailed 3D design, modeling, and drafting of components and assemblies across reactor, shielding, structural, and thermal-management systems. You’ll collaborate closely with engineers and scientists to translate conceptual designs into manufacturable hardware — from CAD models to test prototypes to production drawings. Key Responsibilities Develop 3D models and detailed drawings for reactor subsystems, enclosures, and structural components.Support mechanical design from concept through prototype fabrication and test.Collaborate with systems, thermal, and electrical engineers to ensure proper integration and performance.Perform tolerance analysis, design for manufacturability (DFM), and design for assembly (DFA).Manage CAD data and drawing releases within PLM systems.Support supplier engagement, prototype fabrication, and part inspection.Assist in design verification through simulation and testing (thermal, vibration, mechanical).Contribute to design reviews and maintain design documentation. Qualifications Minimum of a Bachelor’s degree in Mechanical Engineering, Aerospace Engineering, Nuclear Engineering or related discipline.6+ years of experience in mechanical design for aerospace, nuclear energy, defence tech, or advanced manufacturing applications.Strong proficiency with CAD tools (SolidWorks, or Siemens NX preferred).Familiarity with GD&T, ASME Y14.5 drawing standards, and tolerance stack-up analysis.Experience designing for harsh or high-temperature environments is an asset.Bonus for design experience for applications in vacuum.Experience with NPI/NPD policy/process creation.Experience with PLM/ALM integration (bonus Siemens TeamCenter)Hands‑on experience with prototype assembly, machining, or fabrication preferred.Strong teamwork and communication skills, with attention to technical detail and documentation.Curiosity and drive to design real hardware for frontier technologies. Why Join CSMC The chance to help shape the future of energy, space, and defense in CanadaExposure to cutting edge technologies, with mentorship from experienced founders and executivesA collaborative, mission‑driven culture with a flat hierarchy and room for rapid growthEquity participation in a high‑growth startup The candidate must be a highly motivated self‑starter, capable of working through complex issues to solve problems that are not off the shelf. They should be capable of moving through setbacks and finding ways to persevere. Must be eligible to work in Canada, and able to attain appropriate security clearances requisite with an aerospace & nuclear company of this type, and commensurate nuclear engineering position. Candidates will be subject to background checks. This is a second floor opportunity (on a space elevator). This is about an opportunity to learn, be given responsibility, and grow with the company. We have an affinity for diverse people and thinkers with unique perspectives and life experience. CSMC is an equal opportunity employer supporting diversity and inclusion. Email resumes and cover letters to: people@csmc-scms.ca Seniority level Mid‑Senior level Employment type Internship Job function Engineering and Information Technology Industries Aviation & Aerospace #J-18808-Ljbffr