Senior Control Software Engineer

About Commonwealth Fusion Systems:

Commonwealth Fusion Systems is on a mission to deliver the urgent transition to fusion energy.

Combining decades of research, top talent, and new technologies, we’re designing and building commercially viable fusion power plants. And working with policymakers and suppliers to build the energy industry of the future.

We’re in the best position to make it happen. Since 2018, we’ve raised nearly $3 billion in capital, making us the largest and leading private fusion company in the world.

Now we’re looking for more thinkers, doers, builders, and makers to join us. People who’ll bring new perspectives, solve tough problems, and thrive as part of a team.

If that’s you and this role fits, we want to hear from you.

As a Control Software Engineer, you will be responsible for the design, implementation, and verification of software and controls for advanced R&D equipment and complex machinery.

As a member of the Software Engineering team you will be a hands‑on technical contributor, a champion of writing excellent quality, production‑ready code for mission‑critical real‑time systems. You will collect functional requirements from customers and produce software solutions to meet these requirements.

You will work with a variety of engineers to integrate your software into software testbeds, hardware testbeds, and the production tools. You will also contribute to the broader software ecosystem to improve tooling and processes used across the company.

• Develop control software across multiple platforms, including PLCs and real‑time Linux
• Develop operator interfaces and workflows
• Improve software tooling to increase developer velocity and enable new capabilities

• Bachelor's degree in a relevant engineering field (computer science, computer engineering, electrical engineering, industrial engineering, etc.)
• Several years of experience with industrial control systems and/or embedded control systems
• Several years of experience in producing production quality control software
• Working knowledge of modern software development lifecycle practices (CI/CD, git version control, unit testing, integration testing, etc)
• Proficiency with python
• Proficiency with at least one real‑time control language (c++, SCL/ST, rust, etc)

• Familiarity with industrial control platforms (e.g. Beckhoff Twin Cat)
• Familiarity with Linux
• Experience with industrial protocols (e.g. Ether Cat, Profinet, Modbus, etc)
• Familiarity with general networking (IP/UDP)

• Ability to occasionally lift up to 50 lbs
• Perform activities such as stooping, climbing, typing, standing, sitting, etc. for extended periods of time
• Dedication to safety to mitigate industrial hazards that may include heat, cold, noise, fumes, strong magnets, lead (Pb), high voltage, high current, pressure systems, and cryogenics
• Willingness to occasionally travel or work required nights/weekends/on‑call

$140,000 - $200,000 a year

• Competitive compensation with equity
• 12.5 Company‑wide Holidays
• Flexible vacation days
• 10 sick days
• Generous parental leave policy
• Health, dental, and vision insurance
• 401(k) with employer matching
• Professional growth opportunities
• Team‑building activities

#LI-Onsite

At CFS, we excel in fast‑paced environments, driven by our values of integrity, execution, impact, and self‑critique. As we grow, we’re eager to bring on mission‑driven folks who offer diverse perspectives and fresh ways to tackle challenges.

We value diversity deeply and are proud to be an equal opportunity employer by choice. We consider all qualified applicants equally, regardless of race, color, national origin, ancestry, citizenship status, protected veteran status, religion, physical or mental disability, marital status, sex, sexual orientation, gender identity or expression, age, or any other basis protected by law.

This role requires compliance with U.S. laws concerning the export of controlled or protected technologies or information (collectively, “Export Control Laws