Senior Security Risk Engineer

Muon seeks a Senior Security Risk Engineer to join their Security Engineering & IT team. The ideal candidate brings 5+ years of deep expertise across multiple security domains and can operate independently to protect Muon’s infrastructure, data, and people.

The role focuses on security risk — identifying, assessing, and helping address risks across the environment and every company function, from engineering and IT to operations, finance, and the supply chain. You will run risk assessments, prioritize what matters most, drive remediation with the teams that own it, and give leadership a clear, current picture of Muon’s risk posture, including compliance efforts such as NIST 800-171 and ITAR/EAR.

This position may be fully on-site at their San Jose office, hybrid, or fully remote from an approved U.S. location.

Responsibilities:

• Lead security risk assessments across the company — identify, analyze, and prioritize risks across engineering, IT, operations, and business functions
• Maintain a risk register and provide a clear, current view of Muon’s risk posture for leadership
• Partner with teams across the company to drive remediation of identified risks and track them to closure
• Assess the security risk of new tools, vendors, third parties, and architectural or process changes before adoption
• Define and apply a consistent risk framework and methodology — likelihood and impact scoring, risk acceptance, and exceptions
• Map risks and controls to compliance requirements such as NIST 800-171 and CMMC, and support audits and assessments
• Report risk trends and metrics to leadership and recommend where to invest to reduce the most risk
• Help teams build risk-aware processes and take ownership of the risks they hold

Qualifications:

• 5+ years in information security, security engineering, or security risk/GRC roles
• Hands-on experience running security risk assessments and managing a risk register
• Strong understanding of security risk frameworks and methodologies (e.g., NIST RMF / 800-30, FAIR, or similar)
• Familiarity with compliance frameworks such as NIST 800-171, CMMC, SOC 2, or ISO 27001
• Excellent written and verbal communication skills — able to convey risk and priorities to both engineers and leadership

Nice-to-Have Skills:

• Relevant certifications (CISSP, CRISC, CISA, or similar)
• Background in environments subject to ITAR/EAR export control requirements