About the role

The Security Engineer will handle escalated security incidents, manage security toolsets, and perform vulnerability lifecycle tasks. They will also collaborate with senior engineers to execute security projects and maintain detailed technical documentation.

What they look for

Microsoft 365 Entra ID Active Directory Endpoint protection Email security MFA Vulnerability management Windows endpoint hardening Networking fundamentals Identity and access management Troubleshooting Technical documentation PowerShell Incident response Security baselines

Requirements

Candidates must have at least 3 years of experience in IT security or systems administration with strong knowledge of Microsoft 365 and Active Directory. Proficiency in core security tooling, endpoint hardening, and complex technical troubleshooting is required.

Full description

Security Engineer Location: Fair Oaks, CA - 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.