Lead Mechanical/Nuclear Systems Engineer Work Location: Waterloo, ON
About Canadian Strategic Missions Corp. (CSMC) Canadian Strategic Missions Corporation is building the capabilities that will shape Canada's future in space, defence, and energy. We focus on developing dual use systems that address critical challenges here on Earth while enabling sustained human activity beyond it.
In a short time, CSMC has established real momentum. WE have secured significant government investment to advance next generation micro nuclear reactors in partnership with leading institutions, alongside expanding a portfolio of technologies designed for remote environments, national defence, and future space missions. These efforts reflect a broader ambition to deliver reliable power and critical infrastructure where it matters most.
Our work is grounded in close collaboration with government and guided by a clear sense of purpose: to build sovereign capability at a time when it has never been more important. We care deeply about execution, long term impact and earning the trust required to deliver systems that will service Canada and its allies for decades.
CSMC is a company for builders. We are a group of people drawn to hard problems, meaningful impact and the opportunity to shape systems that matter at national and global scale. We are building a team that thrives in ambiguity, values execution, and is motivated by mission and impact.
About the Role CSMC is developing a microreactor for strategic and remote applications. We are hiring a Lead Mechanical and Nuclear Systems Engineer to take ownership of the mechanical and pressure boundary design for core reactor subsystems. This includes the Reactor Pressure Vessel, the primary pressurized loop, and the emergency cooling systems.
This is a technical leadership role. It is not a people management position, although the successful candidate may eventually supervise a small group as the program grows. The focus is on robust engineering judgment, disciplined design work, and the ability to guide mechanical and nuclear systems development from early concept through detailed design.




Key Responsibilities Reactor Pressure Vessel and Primary Loop Design Lead the mechanical design of the Reactor Pressure Vessel using analysis and simulation results from the nuclear science team
Define interfaces for instrumentation and control, penetrations, nozzles, and structural integration
Own the design of the primary pressurized loop including piping, valves, pumps, heat exchangers, and other pressure boundary components
Lead the design of emergency cooling systems including passive and active heat removal pathways
Pressure Boundary Engineering and Code Compliance Develop designs that comply with the following codes and standards
ASME Section III Class 1, 2, and 3
ASME Section VIII
CSA N285
CSA N286 and N299
Perform or oversee stress analysis, thermal hydraulic integration, materials selection, and fabrication considerations
Systems Integration and Technical Leadership Serve as the technical lead for mechanical and nuclear systems across the microreactor program
Work closely with neutronics, thermal hydraulics, instrumentation and control, and safety engineering teams
Translate simulation results into mechanical design requirements
Lead design reviews, hazard analyses, and configuration control for mechanical systems
Design Documentation and Engineering Governance Produce engineering drawings, specifications, design reports, and code compliance documentation
Support early licensing documentation including design descriptions and safety basis inputs
Help establish early engineering processes, standards, and design control practices
Prototyping, Testing, and Vendor Engagement Support fabrication planning, prototyping, and supplier qualification for pressure boundary components
Work with vendors on manufacturability, materials, inspection methods, and quality requirements
Required Qualifications Technical Background Degree in Mechanical Engineering, Nuclear Engineering, or a related field




Seven to fifteen years of experience in mechanical or nuclear systems design for pressure boundary components
Experience with pressure vessel design, piping and loop systems, heat transfer components, high pressure and high temperature systems, and safety critical mechanical systems
Code and Standards Expertise Hands on experience with ASME Section III, ASME Section VIII, CSA N285, and CSA N286 and N299
Experience preparing code compliant design documentation and calculations
Engineering Leadership Proven ability to act as a technical lead on complex mechanical or nuclear systems
Experience leading design reviews and guiding junior engineers
Preferred Experience Experience with microreactors, small modular reactors, or advanced reactor concepts
Experience with thermal hydraulic analysis tools such as RELAP5, TRACE, or MOOSE based codes
Familiarity with defence sector engineering environments
Naval nuclear design experience
Experience with emergency cooling systems, passive safety systems, or high reliability mechanical systems
Why Join CSMC CSMC is building technologies that will shape Canada’s future in energy, space, and national security. You’ll join a team of engineers, scientists, and mission‑driven builders who care deeply about solving hard problems that matter. We move quickly, support each other, and take pride in doing work that has real impact. Along the way, you’ll have access to competitive compensation, benefits, and equity, and the chance to grow with a company that values ownership, curiosity, and technical excellence.
Employment Eligibility CSMC works with highly sensitive nuclear, defence, and aerospace technologies, and all roles require eligibility for federal security screening and compliance with controlled goods and export regulations. Candidates must be legally authorized to work in Canada, able to obtain and maintain Government of Canada security clearance, and eligible to meet foreign affiliation and export control requirements. These conditions are mandatory bona fide occupational requirements and reflect the need to securely develop and protect nationally significant capabilities.

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📌 Lead Mechanical/Nuclear Systems Engineer (Ontario)
🏢 CSMC
📍 Ontario