Senior Software Engineer, Cybersecurity
About Helion
We are a fusion power company based in Everett, WA, with the mission to build the world's first fusion power plant, enabling a future with unlimited clean electricity. Our vision is a world with clean, reliable, and affordable energy for everyone.
Since Helion's founding in 2013, we have raised $1.5 billion from long-time investors such as Sam Altman, Mithril, and Capricorn Investment Group as well as new investors including Thrive Capital, LightSpeed Venture Capital, SoftBank, and others to propel us forward. Our current prototype, Polaris, has reached record-breaking plasma temperatures of 150 million degrees Celsius (13 keV). Helion is continuing to iterate and on the path to the world's first fusion power plant, Orion.
This is a pivotal time to join Helion. You will tackle real-world challenges with a team that prizes urgency, rigor, ownership, and a commitment to delivering hard truths – values essential to achieving what no one has before. Together, we will change the future of energy, because the world can't wait.
What You Will Be Doing:
As a Cybersecurity Software Engineer focused on product security, you will ensure that the firmware, software, and server infrastructure driving our fusion machines are resilient against attack. You’ll work closely with firmware, software, and infrastructure engineers to embed security into every stage of the development lifecycle—reviewing designs, auditing code and dependencies, and integrating security checks into CI/CD pipelines. You’ll lead initiatives in encryption, secrets management, and secure authentication to protect sensitive machine operations. Beyond building defenses, you’ll champion security best practices across the organization, providing both the tools and the guidance to enable engineers to move quickly without sacrificing safety. This role is ideal for someone who wants to blend deep cybersecurity expertise with hands-on engineering to safeguard one of the most advanced energy technologies being built today. This is an onsite role that reports directly to the Lead Electrical Engineer at our Everett, WA office.
You Will:
Review firmware, software, and infrastructure designs to identify and mitigate security risks before implementation
Advocate for and implement security best practices across engineering, such as encryption, key rotation, and secure authentication
Deploy and manage application security tools (e.g., Snyk, Trivy, Docker image scanners) to audit dependencies, supply chain risks, and vulnerabilities
Own the definition and enforcement of product-level secrets management and credential handling
Lead initiatives in software and firmware hardening for production systems, ensuring resilience against potential adversarial attacks
Work with firmware, software, and infrastructure engineers to embed security into CI/CD pipelines and development workflows
Create and maintain internal guidelines for secure coding practices and data classification
Contribute to building institutional trust by ensuring our software and firmware meet high standards of security, reliability, and compliance
Serve as the voice of product security in design reviews, code reviews, and cross-functional engineering efforts
Required Skills:
Strong Linux systems knowledge, including security hardening and permissions management
Proficiency with Git-based workflows and secure software delivery practices
Solid understanding of modern encryption standards (TLS, AES, RSA, ECC) and key management practices
Hands-on experience with security engineering tools (SAST/DAST, dependency scanning, Docker/Kubernetes security, supply chain auditing)
Experience conducting secure code reviews and identifying common vulnerabilities
Strong programming background in at least two of: C++, Rust, Python, Typescript, or Java
Familiarity with vulnerability assessment and mitigation strategies across firmware, software, and server environments
Ability to work collaboratively with multi-disciplinary engineering teams and advocate for security without blocking progress
#LI-Onsite #LI-KL1
Benefits
Our total compensation package includes benefits, including but not limited to:
Medical, Dental, and Vision plans for employees and their families
31 Days of PTO (21 vacation days and 10 sick days)
10 Paid holidays, plus company-wide winter break
Up to 5% employer 401(k) match
Short term disability, long term disability, and life insurance
Paid parental leave and support (up to 16 weeks)
Annual wellness stipend
Helion is an equal opportunity employer and value diversity at our company. We do not discriminate based on race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status. If you need assistance or an accommodation during the interview process, please let us know.