MSP Security Engineer

Fusethree; California (MO); On-site; USD 90,000 - 120,000; Full time

Job summary

FUSE3 is seeking a Security Engineer to join our Information Security team. This mid-level role bridges day-to-day operational security with advanced technical execution, handling escalated tickets and supporting the security toolset across client environments.

You will work with senior engineers to diagnose complex issues, manage threat governance, and contribute to proactive security initiatives while maintaining detailed documentation and efficient incident response.

Qualifications

• 3+ years of experience in IT security, systems administration, or a closely related technical role.
• Strong working knowledge of Microsoft 365 and Entra ID (Azure AD) administration and security.
• Hands-on experience with Active Directory administration and security (Group Policy, identity management, hybrid AD environments).
• Hands-on experience with core security tooling: endpoint detection/response, email security (phishing triage), MFA, and vulnerability management.
• Experience with Windows endpoint hardening and security baselines (e.g., CIS Benchmarks, Microsoft security baselines).
• Ability to troubleshoot and resolve complex technical problems with minimal supervision.
• Solid understanding of networking fundamentals, identity/access management, and common attack vectors.
• Clear written and verbal communication skills; able to document work for colleagues and clients.
• Ability to manage competing priorities across multiple clients or environments.

Responsibilities

• Handle escalated security tickets and incidents requiring deep technical investigation.
• Diagnose, troubleshoot, and resolve complex security and infrastructure issues across client environments.
• Manage the full security toolset; administer and tune tools daily.
• Participate in the vulnerability lifecycle from identification to patching and remediation; run audits and reports.
• Support security project execution including deployments, migrations, and remediation work.
• Assist with incident response activities under senior guidance.
• Create and maintain documentation of procedures, configurations, and resolutions.
• Collaborate with senior engineers to translate security plans into executable work.

Skills

Microsoft 365

Entra ID (Azure AD)

Active Directory

Security knowledge

Windows security

Networking fundamentals

Communication

Prioritization

Tools

Microsoft Defender

Huntress

Duo

SIEM

Graph API

PowerShell

Job description

Security Engineer

Location: Fair Oaks, CA (must be local, within 50 miles)

On-site (hybrid potential after onboarding period)

Employment Type: Full-time

Department: Information Security

Reports to: Security Team Manager

About the Role

FUSE3 is seeking a Security Engineer to join our Information Security team. This is a mid-level role designed to bridge day-to-day operational security work with more advanced technical execution. You will work alongside existing Security Engineers, taking ownership of recurring operational tasks, resolving escalated technical issues, and supporting the ongoing management of our security toolset across our client base. The ideal candidate is technically capable of working independently on complex problems, but also dedicated to owning the steady, recurring work that keeps a security practice running. You'll approach your work with intention, put the team's needs alongside your own, and be a key contributor to keeping both reactive and proactive security functions moving.

Key Responsibilities

• Handle escalated security tickets and incidents that require deeper technical investigation than front-line triage, working within our ticketing/PSA platform to track and resolve issues
• Independently diagnose, troubleshoot, and resolve complex security and infrastructure issues across client environments
• Help manage the full security toolset (endpoint protection, email security, MFA, vulnerability management, and related platforms), and own the day-to-day administration and tuning of assigned tools
• Participate in the full vulnerability lifecycle from identification through patching and remediation alongside recurring tasks such as alert triage, configuration audits, and reporting
• Support security project execution, including deployments, migrations, and remediation work
• Assist with incident response activities under the direction of senior team members
• Create and maintain clear, reusable documentation of procedures, configurations, and resolutions in the team's knowledge base
• Collaborate with senior engineers to translate security plans into executed work

Required Qualifications

• 3+ years of experience in IT security, systems administration, or a closely related technical role
• Strong working knowledge of Microsoft 365 and Entra ID (Azure AD) administration and security
• Hands-on experience with Active Directory administration and security (Group Policy, identity management, hybrid AD environments)
• Hands-on experience with core security tooling: endpoint detection/response, email security (including phishing triage), multi-factor authentication, and vulnerability management
• Experience with Windows endpoint hardening and security baselines (e.g., CIS Benchmarks, Microsoft security baselines)
• Demonstrated ability to independently troubleshoot and resolve complex technical problems with minimal supervision
• Solid understanding of networking fundamentals, identity/access management, and common attack vectors
• Clear written and verbal communication skills, including the ability to document technical work and communicate effectively with both colleagues and clients
• Ability to manage competing priorities across multiple clients or environments

Desired Skills

• Experience in an MSP (Managed Service Provider) or multi-tenant environment
• PowerShell scripting and automation experience (Graph API or similar a plus)
• Exposure to SIEM platforms and log analysis for investigation and incident review
• Familiarity with security frameworks (e.g., CIS, NIST, SOC 2)
• Experience with tools such as Microsoft Defender, Huntress, Duo, or comparable platforms
• Familiarity with common AI tools and their practical application to security and IT work (e.g., using AI assistants for research, documentation, scripting, and analysis)
• Relevant certifications (Security+, SC-200, SC-300, AZ-500, or working toward CISSP)
• A proactive mindset, able to identify recurring problems and resolve them at the root rather than repeatedly reacting to symptoms

Soft Skills & Growth

• A genuine desire to learn and grow. You see gaps in your knowledge as opportunities and actively work to close them
• Personable and collaborative, able to build trust with teammates and clients through clear, respectful communication
• Selfless in your approach to the team, willing to take on the unglamorous work, share what you know, and support your colleagues' success
• Intentional and dependable, bringing focus and follow-through to both routine tasks and complex problems, and taking full ownership of your responsibilities

What Success Looks Like

Within the first 6 months, this person will independently own a defined set of operational security functions and serve as a reliable escalation point for reactive work freeing senior engineers to focus on high-level planning, architecture, and strategic execution.