Develops autonomous microreactors for remote power
Tooling Design Engineer 2-Senior
Full-Time
$115k - $190k/yr
Mid, Senior
Bachelor's
Los Angeles, CA, USA
In Person
Mechanical EngineeringDesign Engineering
About the job
Requirements
A bachelor's degree in Mechanical Engineering, Aerospace Engineering, Manufacturing Engineering, or a related technical discipline is required.
At least 3 years of experience designing mechanical hardware, tooling, fixtures, ground support equipment, manufacturing equipment, or similar systems is required.
Strong 3D CAD skills and experience developing production-quality engineering drawings are required.
Ability to take mechanical designs from initial concept through detailed design, fabrication, assembly, and implementation is required.
Experience designing hardware for practical use in manufacturing, assembly, test, installation, maintenance, or field operations environments is required.
Strong understanding of mechanical design fundamentals, including tolerance stack-ups, fits, fasteners, structural loading, material selection, and design for manufacturing and assembly is required.
Ability and willingness to support tooling installation, checkout, and operation in both factory and field environments is required.
Responsibilities
Own the design, development, fabrication, qualification, and implementation of tooling and ground support equipment for manufacturing, assembly, testing, transport, installation, service, and decommissioning of Antares R1 microreactors.
Work with manufacturing, test, reactor hardware, operations, quality, and deployment teams to understand hardware build and handling needs and translate them into engineering solutions.
Develop tooling concepts from first principles while balancing safety, usability, manufacturability, schedule, cost, reliability, and factory and field constraints.
Create detailed 3D CAD models, assemblies, and engineering drawings for fixtures, handling equipment, lifting devices, assembly tooling, test support equipment, transportation fixtures, installation equipment, and other specialized mechanical systems.
Perform mechanical design and basic engineering analysis to ensure tooling is structurally adequate, stable, safe to operate, and suitable for intended loads and environments.
Design tooling for operator ergonomics, access, alignment, tolerance stack-up, repeatability, mistake-proofing, inspection access, maintainability, and integration into manufacturing and test workflows.
Work hands-on with machinists, welders, technicians, suppliers, and engineers to fabricate, assemble, troubleshoot, modify, and commission tooling.
Direct and support the initial use of new tooling on the factory floor and at deployment sites, incorporating operator feedback and observed performance into rapid design improvements.
Develop ground support equipment and handling solutions for large, heavy, sensitive, or high-value reactor hardware, including equipment for lifting, positioning, alignment, transportation, installation, and removal.
Support integrated reactor and subsystem testing by developing fixtures, test stands, interfaces, temporary structures, and other equipment needed to safely configure and operate development and qualification hardware.
Develop tooling and equipment for reactor transportation and site deployment, accounting for packaging, shipping, field handling, limited site infrastructure, environmental conditions, and installation sequence.
Partner with deployment and reactor engineering teams to develop tooling concepts and procedures for future maintenance, removal, and decommissioning, incorporating lifecycle handling considerations into reactor design early.
Generate and maintain engineering definition for tooling, including drawings, bills of material, specifications, load requirements, operating limits, inspection requirements, and supporting documentation.
Work with suppliers and internal fabrication teams to source components and manufacture tooling, resolving fabrication issues and making practical design decisions that maintain schedule without sacrificing safety or functionality.
Develop operating instructions, checkout requirements, and safe-use criteria for specialized tooling and support training of technicians and operators responsible for its use.
Participate in design reviews, build readiness reviews, test readiness activities, and field planning to ensure required equipment is identified and available before it becomes a schedule constraint.
Identify opportunities to simplify reactor assembly, test, transportation, and installation through improved tooling, automation, mechanization, or product-design changes.
Serve as the hands-on technical owner for tooling throughout its lifecycle, from initial concept through fabrication, use, modification, maintenance, and retirement.
Desired Qualifications
Siemens NX experience, including complex assemblies, detailed drawings, and configuration-controlled mechanical design.
Experience designing ground support equipment, lifting and handling equipment, assembly fixtures, transportation fixtures, test stands, deployment equipment, or other specialized tooling for aerospace, nuclear, defense, automotive, heavy industrial, or similar hardware.
Experience designing tooling for large, heavy, high-value, or geometrically sensitive hardware requiring controlled lifting, positioning, alignment, or installation.
Experience with lifting and rigging equipment, including understanding load paths, factors of safety, lifting interfaces, and applicable design practices or standards.
Experience performing or reviewing structural calculations or finite element analysis for tooling, fixtures, frames, lifting equipment, or support structures.
Experience supporting integrated hardware testing and developing fixtures, interfaces, temporary structures, or support equipment for test operations.
Familiarity with CNC machining, welding, sheet metal fabrication, structural fabrication, additive manufacturing, and commercial off-the-shelf component selection.
Experience commissioning new equipment on a production floor or at a field site and directly supporting its initial operation.
Experience working in a highly regulated or safety-critical industry such as nuclear, aerospace, spaceflight, defense, energy, or medical devices.
Comfort working in a fast-paced hardware development environment requiring detailed engineering, hands-on problem solving, and rapid execution.
About Us
At Antares, our long-term mission is to make clean energy abundant from Earth to the Asteroid Belt. We’re fueled by the belief that advanced nuclear energy can strengthen our military, solve the climate crisis, elevate global living standards, and expand humanity's presence in outer space. To achieve our mission, we’re building mass-producible, inherently safe, deployable microreactors that can be used terrestrially, underwater, and in space.
The Antares team hails from SpaceX, the White House, the Pentagon, the Department of Energy, MIT, Rigetti Computing, General Atomics, Relativity Space, Ursa Major, and National Laboratories like Idaho, Oak Ridge, Los Alamos, and Savannah River. Antares has raised over $600M in venture capital from top-tier investors and has hundreds of million-dollars on contract with the military services, NASA, and the Department of Energy.
Roles & Responsibilities
Own the design, development, fabrication, qualification, and implementation of tooling and ground support equipment required to manufacture, assemble, test, transport, install, service, and ultimately decommission Antares R1 microreactors.
Work directly with manufacturing, test, reactor hardware, operations, quality, and deployment teams to understand how hardware will actually be built and handled, identify tooling needs, and translate those needs into practical engineering solutions.
Develop tooling concepts from first principles, balancing safety, usability, manufacturability, schedule, cost, reliability, and the constraints of both factory and field environments.
Create detailed 3D CAD models, assemblies, and engineering drawings for fixtures, handling equipment, lifting devices, assembly tooling, test support equipment, transportation fixtures, installation equipment, and other specialized mechanical systems. Siemens NX experience is preferred.
Perform mechanical design and basic engineering analysis necessary to ensure tooling is structurally adequate, stable, safe to operate, and appropriate for its intended loads and environments.
Design tooling with the operator in mind, including ergonomics, access, alignment, tolerance stack-up, repeatability, mistake-proofing, inspection access, maintainability, and efficient integration into manufacturing and test workflows.
Take designs beyond the drawing package by working hands-on with machinists, welders, technicians, suppliers, and engineers to fabricate, assemble, troubleshoot, modify, and commission tooling.
Direct and support the initial use of new tooling on the factory floor and at deployment sites, incorporating operator feedback and observed performance into rapid design improvements.
Develop ground support equipment and handling solutions for large, heavy, sensitive, or high-value reactor hardware, including equipment used for lifting, positioning, alignment, transportation, installation, and removal.
Support integrated reactor and subsystem testing by developing fixtures, test stands, interfaces, temporary structures, and other equipment needed to safely configure and operate development and qualification hardware.
Develop tooling and equipment required for reactor transportation and site deployment, accounting for packaging, shipping, field handling, limited site infrastructure, environmental conditions, and installation sequence.
Partner with deployment and reactor engineering teams to develop tooling concepts and procedures for future maintenance, removal, and decommissioning activities so that lifecycle handling considerations are incorporated into the reactor design early.
Generate and maintain complete engineering definition for tooling, including drawings, bills of material, specifications, load requirements, operating limits, inspection requirements, and supporting documentation.
Work closely with suppliers and internal fabrication teams to source components and manufacture tooling, resolving fabrication issues and making practical design decisions that maintain schedule without sacrificing safety or functionality.
Develop operating instructions, checkout requirements, and safe-use criteria for specialized tooling and support training of technicians and operators responsible for its use.
Participate in design reviews, build readiness reviews, test readiness activities, and field planning to ensure the equipment required to safely execute the work is identified and available before it becomes a schedule constraint.
Identify opportunities to simplify reactor assembly, test, transportation, and installation through improved tooling, automation, mechanization, or changes to the product design itself.
Serve as a hands-on technical owner for tooling throughout its lifecycle, from initial concept through fabrication, use, modification, maintenance, and retirement.
Basic Qualifications:
Bachelor’s degree in Mechanical Engineering, Aerospace Engineering, Manufacturing Engineering, or a related technical discipline.
3+ years of experience designing mechanical hardware, tooling, fixtures, ground support equipment, manufacturing equipment, or similar systems.
Strong 3D CAD skills and experience developing production-quality engineering drawings; Siemens NX experience is preferred but not required.
Demonstrated ability to take mechanical designs from initial concept through detailed design, fabrication, assembly, and implementation.
Experience designing hardware for practical use in manufacturing, assembly, test, installation, maintenance, or field operations environments.
Strong understanding of mechanical design fundamentals, including tolerance stack-ups, fits, fasteners, structural loading, material selection, and design for manufacturing and assembly.
Ability and willingness to support tooling installation, checkout, and operation in both factory and field environments.
Preferred Skills and Experience
Experience designing ground support equipment (GSE), lifting and handling equipment, assembly fixtures, transportation fixtures, test stands, deployment equipment, or other specialized tooling for aerospace, nuclear, defense, automotive, heavy industrial, or similar hardware.
Proficiency with Siemens NX, including complex assemblies, detailed drawings, and configuration-controlled mechanical design.
Experience designing tooling for large, heavy, high-value, or geometrically sensitive hardware requiring controlled lifting, positioning, alignment, or installation.
Experience with lifting and rigging equipment, including understanding of load paths, factors of safety, lifting interfaces, and applicable design practices or standards.
Experience performing or reviewing structural calculations or finite element analysis for tooling, fixtures, frames, lifting equipment, or support structures.
Experience supporting integrated hardware testing and developing fixtures, interfaces, temporary structures, or support equipment for test operations.
Familiarity with common fabrication processes including CNC machining, welding, sheet metal fabrication, structural fabrication, additive manufacturing, and commercial off-the-shelf component selection.
Experience commissioning new equipment on a production floor or at a field site and directly supporting its initial operation.
Experience working in a highly regulated or safety-critical industry such as nuclear, aerospace, spaceflight, defense, energy, or medical devices.
Comfortable working in a fast-paced hardware development environment that requires a blend of detailed engineering, hands-on problem solving, and rapid execution.
Compensation:
Tooling Design Engineer II: $115,000-$150,000
Senior Tooling Design Engineer: $140,000-$190,000
Location
We are located in Torrance, CA in a 145,000 square foot, brand new facility featuring large open spaces for team collaboration, R&D, and production, as well as easy access to the 405, 105, and 110 freeways. Our facility is in the heart of Los Angeles' vibrant emerging tech ecosystem alongside many other high growth startups and enterprises.
Culture
At Antares, we like to specifically tie each role to our founding document’s set of values–here are the top five cultural values we think you should believe at your core to be successful:
Think in Systems - Energy and Defense are complex ecosystems with numerous stakeholders with competing priorities, conflicting policies, perverse incentives, and emergent and path-dependent properties. First principles thinking alone is insufficient. Think probabilistically and then take action. “If you want to be certain, then you are apt to be obsolete.” Over-optimizing the components often degrades the system
Obsess over the End User - The customer and end user are often not the same. We will never build globally competitive commercial products if we lose sight of our end users and their entire interaction with the product life cycle
Be Unconstrained by Convention - Our only limits are the laws of physics. Many, even experts, will say what we are working on is impossible. They said the same about SpaceX reusing rockets. Generationally impactful companies, by definition, must accomplish the seemingly impossible. If it were easy, it would have already been done. Never shy away from a solution because it has never been tried before, and never choose to do something because that's “how it's always been done”
Go Where the Work Is - Never miss a chance to meet a customer, user, or stakeholder face to face, even if that means hopping on a plane. If you can’t make it, find a teammate who can channel your intentions and go in your place. Deep work can be done from anywhere, but we believe teams are built in person, and aim to maximize our time together
Operate in the Grey - Embrace nuance in pursuit of truth. Question every fundamental assumption
Equal Opportunity
Antares is an Equal Opportunity Employer. Employment decisions are based solely on merit, competence, and qualifications, without regard to race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability, or any other legally protected status.
ITAR Requirements
To conform to U.S. Government export regulations, applicant must be a (i) U.S. citizen or national, (ii) U.S. lawful, permanent resident (aka green card holder), (iii) Refugee under 8 U.S.C. § 1157, or (iv) Asylee under 8 U.S.C. § 1158, or be eligible to obtain the required authorizations from the U.S. Department of State. Learn more about the ITAR here.
Exosens supports the accelerating deployment of next-generation nuclear technologies in the U.S.
October 08, 2026 12:00 ET | Source: Exosens
* Key milestones achieved under the U.S. Department of Energy's Reactor Pilot Program highlight the accelerating deployment of next-generation nuclear technologies
* Exosens' advanced neutron flux monitoring detectors supported successful criticality demonstrations by Antares Nuclear and Valar Atomics, underscoring the relevance of its technologies across Small Modular Reactor (SMR) applications
* These achievements are expected to translate into near-term pre-series production orders and support long-term demand for Exosens' nuclear instrumentation solutions
Press release, Mérignac (France), 8 October 2026 - Exosens (EXENS; FR001400Q9V2), a high-tech company focused on providing mission- and performance-critical amplification, detection and imaging technologies, today announces its contribution to two successful criticality demonstrations for next-generation nuclear reactors under the U.S. Department of Energy's Reactor Pilot Program.
In August 2025, the program initially selected 11 advanced reactor projects with the goal of bringing at least three reactor designs to criticality by 4 July 2026. The program exceeded that objective, with four projects reaching this milestone by the deadline. These achievements mark a decisive step towards the commercial deployment of next-generation nuclear technologies on an accelerated timeline in the United States, particularly across SMR applications.
Against this backdrop, Exosens supplied high-performance neutron detectors and related technical expertise to Antares Nuclear and Valar Atomics, the developers behind the first two reactor designs to reach criticality as part of the DOE's Reactor Pilot Program. Integrated into safety-related neutron flux monitoring systems, these advanced detectors provide the measurements required to monitor reactor power and track the approach to criticality during start-up and testing.
These achievements are expected to translate into pre-series production orders in the near term and support long-term demand for Exosens' nuclear instrumentation solutions across the U.S. market.
"The move towards commercial deployment of next-generation nuclear technologies is accelerating in the United States, supported by increasing demand for reliable, carbon-free power, notably to meet the unprecedented energy requirements of AI-enabled data centers. This momentum is reinforcing investment in SMR technologies and driving demand for high-performance instrumentation designed for demanding nuclear environments, creating significant long-term growth opportunities for Exosens. Already providing advanced nuclear detection solutions for seven SMR-related projects across the United States and Europe, Exosens leverages its differentiated technologies, deep nuclear expertise and industrial capabilities to address these needs and support the long-term development of the SMR market," said Jérôme Cerisier, CEO of Exosens.
"Achieving criticality is a defining milestone in next-generation reactor development. The progress made by Antares Nuclear and Valar Atomics demonstrates the pace of innovation across the U.S. nuclear industry. We are proud to have supported these successful demonstrations through Exosens' advanced neutron flux monitoring technologies, and look forward to helping reactor developers as they move from first-of-a-kind testing towards safe, reliable commercial deployment," said Cyril Barre, Nuclear Instrumentation Director at Exosens.
Financial calendar
* 27/10/2026: 9M 2026 revenue and adjusted gross margin (before market opening).
* 22/02/2027: FY 2026 results (before market opening).
About Exosens
Exosens is a high-tech company with more than 85 years of experience in the innovation, development, manufacturing and sale of high-end electro-optical technologies in the fields of amplification, detection and imaging. Today, it offers its customers detectors and imaging solutions such as digital cameras, ion, electron, neutron and gamma-ray detectors as well as image intensifier tubes. This enables Exosens to address complex challenges in extremely demanding environments by providing its customers with tailor-made solutions. Thanks to its sustained investment, Exosens is internationally recognized as a major innovator in optoelectronics, with production and R&D activities carried out at 13 sites across Europe and North America and more than 2,000 employees. Exosens is listed on compartment A of the regulated market of Euronext Paris (Ticker: EXENS - ISIN: FR001400Q9V2). Exosens is a member of the Euronext Tech Leaders segment and is also included in several indices, including SBF 120, CAC All-Tradable, CAC Mid 60, FTSE Total Cap and MSCI France Small Cap. For more information: www.exosens.com.
Investor Relations
Media Relations
Louisiana-based nuclear microreactor startup Antares has secured a $161 million Strategic Breakthrough award from the US Space Force to develop nuclear power systems for future space missions. The funding represents one of the largest current US defence investments in space nuclear power.
Antares will first demonstrate its R1-S reactor design on the ground before integrating it with a spacecraft for flight certification. The company plans to begin testing its Mark-1 reactor in 2027, which will operate for over six months during the test campaign.
The startup achieved a significant milestone in June when its Mark-0 microreactor reached initial criticality at Idaho National Laboratory, making Antares the first private company to achieve advanced-reactor criticality under the Department of Energy's Reactor Pilot Program.
The US has not operated a nuclear reactor in space since NASA's SNAP-10A mission in 1965.
Antares wins $161 million Space Force award for nuclear reactor demonstration.
September 11, 2026
Rendering of a nuclear-powered spacecraft in Earth orbit
Antares has been selected for a $161 million Strategic Breakthrough award to demonstrate nuclear power technology for space, giving the nuclear energy company a path to test its R1-S reactor on the ground and integrate the system with a spacecraft ahead of flight certification and launch.
The award was made through the Office of the Assistant Secretary of the Air Force for Space Acquisition and Integration and represents the largest Department of War award for space nuclear power to date, according to Antares.
Under the program, Antares will conduct a nuclear ground demonstration of its R1-S system before integrating the reactor with a spacecraft for flight certification. The work moves the company's compact fission technology toward an operational space mission rather than limiting development to reactor testing.
Antares will also use Mark-1, its electricity-producing reactor, to power an operational ground-to-space asset. Testing of Mark-1 is scheduled for 2027, creating another step in validating how the company's reactor and power-conversion technologies perform as an integrated energy system.
"This partnership with the Space Force turns that long-held vision into a codified space mission," CEO and co-founder Jordan Bramble said. "Fission will unlock strategic capabilities that are impossible today."
The program addresses one of the central infrastructure constraints for more power-intensive spacecraft: generating reliable electricity while maintaining sufficient propulsion capacity for maneuvering. Nuclear fission could provide continuous power for systems with heavier computing requirements and other high-demand payloads without depending on conventional spacecraft power architectures alone.
Antares is targeting applications including advanced computing, directed-energy systems and electromagnetic warfare. The company also sees nuclear power as a way to reduce propulsion-related operational constraints, potentially allowing spacecraft to conduct more dynamic maneuvers while maintaining power for onboard systems.
The award builds on a reactor milestone Antares reached earlier this year. On June 4, 2026, its Mark-0 microreactor achieved initial criticality at Idaho National Laboratory under Department of Energy authorization. Antares said the milestone made it the first private company to bring an advanced reactor to criticality through the DOE Reactor Pilot Program.
The next stage centers on producing usable electricity. Antares plans to operate its Mark-1 reactor for more than six months in 2027, integrating it with the company's nitrogen closed Brayton cycle power-conversion system. That configuration is designed to move development beyond reactor physics and demonstrate an integrated system capable of converting reactor heat into electricity.
Successfully coupling the reactor with power conversion is an important operational requirement for both terrestrial and space applications. The company's development sequence moves from Mark-0 criticality to extended Mark-1 electricity production, followed by the R1-S ground demonstration and spacecraft integration required for a potential flight mission.
The Strategic Breakthrough program also aligns with federal plans to accelerate deployment of nuclear power beyond Earth. Antares said the award supports goals established by Executive Order 14369, "Ensuring American Space Superiority," and the National Initiative for American Space Nuclear Power established through NSTM-3. Those policies call for nuclear reactors to be launched into space as early as 2028 and deployed on the lunar surface by 2030.
Founded in 2023, Antares is developing compact nuclear microreactors for defense and space applications. The company has raised more than $600 million and expects initial production deployments at U.S. military installations beginning in 2028.
Antares operates facilities in Torrance, California; Idaho Falls, Idaho; and Aiken, South Carolina. The $161 million award adds a dedicated space mission to a development program that is now moving from reactor criticality toward electricity generation, spacecraft integration and eventual deployment.
Antares wins $161M award for space nuclear power.
Friday September 11, 2026 Waxing Crescent
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Antares selected for $161M Strategic Breakthrough award to demonstrate space reactor.
Published at September 11th 2026, 10:28 AM EDT via Business Wire
i This article is third-party content and does not represent the views of this site. We make no guarantees regarding its accuracy or completeness.
Effort will carry a nuclear-powered spacecraft toward flight qualification
Nuclear Energy
Antares today announced it has been selected by the Office of the Assistant Secretary of the Air Force for Space Acquisition and Integration for a Strategic Breakthrough award to advance nuclear power for space. It marks the largest current Department of War award in space nuclear power.
Rendering of a nuclear-powered spacecraft in Earth orbit
"Space has been core to the Antares thesis since the company was founded," said Jordan Bramble, CEO and co-founder of Antares. "This partnership with the Space Force turns that long-held vision into a codified space mission. Fission will unlock strategic capabilities that are impossible today."
Through this program, Antares will perform a nuclear ground demonstration of the R1-S and integrate with a spacecraft for flight certification forward of launch. The company will also power an operational ground-to-space asset with Mark-1, its electricity-producing reactor, scheduled for testing in 2027.
Space nuclear has been core to Antares from day one. It removes propulsion constraints for the Space Force, allowing spacecraft to maneuver without regret and carry out dynamic operations that were once impossible. Most importantly, it brings high, always-on power to support heavier compute loads, directed energy systems, and the future of electromagnetic warfare.
On June 4, 2026, Antares' Mark-0 microreactor achieved initial criticality at Idaho National Laboratory under Department of Energy authorization, making Antares the first private company to bring an advanced reactor to criticality under the DOE Reactor Pilot Program. The company's Mark-1 reactor is scheduled to operate for more than six months in 2027, integrated with its nitrogen closed Brayton cycle power conversion system.
The award supports goals set in Executive Order 14369, "Ensuring American Space Superiority," and the National Initiative for American Space Nuclear Power established by NSTM-3, which direct the launch of nuclear reactors in space as early as 2028 and on the lunar surface by 2030.
About Antares
Antares is a nuclear fission energy company developing compact microreactors for defense and space applications, delivering safe, reliable power where traditional energy sources cannot. Founded in 2023 and backed by over $600 million in funding, Antares achieved initial criticality of its Mark-0 microreactor in 2026 under the DOE Reactor Pilot Program, and is on track to produce electricity from an advanced reactor in 2027, with initial production deployments to U.S. military installations beginning in 2028. Antares operates facilities in Torrance, California; Idaho Falls, Idaho; and Aiken, South Carolina.
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