Senior Manager – Cybersecurity Operations

Castelion Corporation•Torrance, CA

About The Position

We are seeking an experienced Senior Manager – Cybersecurity Operations to join our cybersecurity operations team at Castelion. This critical role will lead defensive security operations, incident response, and threat monitoring, protecting our information systems, intellectual property, product development security, and critical infrastructure from common threat vectors as well as advanced persistent threats (APTs) and nation-state actors. The ideal candidate will envision security to remain a business enabler and not a blocker, have deep expertise in defensive security operations, SOC leadership, proactive threat hunting, SIEM & SOAR, and incident response within highly regulated environments. Brings a practical, and up-to-date relevant technical understanding of protocols, encryption levels, patch levels, policy & procedure, etc., that are secure in the modern cybersecurity landscape.

Requirements

7+ years of hands-on experience in cybersecurity, with a focus in defensive operations
2+ years in a leadership or team lead capacity
Proven experience operating in defense, aerospace, engineering, intelligence, government, or critical infrastructure sectors
Experience in regulated environments (DoD, CMMC, NIST 800-171, ISO 27001, etc.)
Demonstrated expertise in security monitoring, threat hunting, and incident response
Demonstrated understanding of advanced persistent threat (APT) tactics and techniques
Hands-on experience with enterprise security tools (SIEM, EDR, IDS/IPS, firewalls, proxies)
Expert knowledge of network protocols, security architecture, and system hardening
Expert proficiency as both a configurator and a consumer of security information and event management (SIEM) platforms
Strong understanding of Windows and Linux security and forensics
Experience with endpoint detection and response (EDR) solutions (CrowdStrike, Carbon Black, Defender, SentinelOne, etc.)
Proficiency with scripting and automation (Python, PowerShell, Bash)
Knowledge of cloud security (AWS, Azure, GovCloud)
Understanding of malware analysis, reverse engineering techniques, and penetration testing
Experience with threat intelligence platforms and indicator management
Deep understanding of security principles, threats, and frameworks (e.g., cyber kill chain, MITRE ATT&CK, NIST, CIS Controls).
Strong documentation, troubleshooting, and communication skills.
Ability to thrive in fast-paced, high-pressure environments with competing priorities.
Analytical mindset with strong problem-solving abilities
Commitment to staying current with evolving threat landscape

Nice To Haves

Active Security+, CISSP, GIAC, GSOC, GCIA, GCIH, GCFA, CISA, CEH, or similar senior-level certifications
Eligibility to keep and maintain a U.S. security clearance.

Responsibilities

Contribute to and mature our Security Operations Center (SOC) activities and ensure effective threat detection and response
Direct threat hunting operations to proactively identify and neutralize threats before impact
Lead incident response efforts for security events affecting all our information systems
Develop and maintain defensive playbooks, runbooks, and standard operating procedures
Coordinate with additional internal teams to conduct exercises that validate defensive posture
Design and implement defense-in-depth strategies aligned with NIST, DoD, and intelligence community frameworks
Evaluate and deploy advanced security technologies (SIEM, EDR/XDR, SOAR, threat intelligence platforms)
Create and maintain security architecture documentation and network defense diagrams
Contribute to security roadmap planning
Establish and maintain threat intelligence program aligned to aerospace and defense sector threats
Analyze threat actor tactics, techniques, and procedures (TTPs) using MITRE ATT&CK framework
Produce threat intelligence reports and briefings for technical and executive audiences
Collaborate with government agencies and industry partners on threat information sharing
Track emerging threats and vulnerabilities relevant to defense systems and aerospace technology
Contribute to compliance with NIST 800-171, CMMC, ITAR, DFARS, and other applicable regulations
Support security audits, assessments, accreditation activities, and regular penetration testing
Partner with IT operations, engineering, and program management teams on security initiatives
Coordinate with government customers and oversight bodies on security matters

Benefits

Meaningful long-term equity
Four (4) weeks of paid time off
Ten (10) company-paid holidays
Comprehensive health benefits - including 100% employee-covered medical and strong dependent coverage, along with dental and vision plans.
Paid parental leave
$100 monthly fitness stipend
Onsite EV charging
Catered meals
Company-covered food during high-demand periods
Fully stocked kitchen