Sr Network and Security Engineer

We are looking for an experienced Senior Network & Security Engineer to design, implement, and secure our enterprise network and infrastructure environment across five OpCos in multiple states. Reporting to the IT Director and partnering closely on security and infrastructure strategy, this is a hands-on role — you will execute the day-to-day engineering work while helping shape the organization's technical direction. Cybersecurity is at the core of this role — you will help harden our environment, enforce zero-trust principles, and defend against evolving threats, while ensuring reliability and scalability across all OpCos and systems. Operating as part of a shared services team, you will help standardize IT and security practices across the OpCos, and this role also plays a key part in the design and buildout of secure office network infrastructure for new and renovated spaces.

Security

• Support the organization's cybersecurity strategy, hardening, and defense-in-depth posture across all OpCos
• Administer ThreatLocker Zero Trust policies for application allowlisting, ringfencing, and endpoint control
• Monitor, investigate, and respond to threats and alerts from Huntress and Arctic Wolf managed detection and response
• Manage SonicWall firewalls across all OpCos, including security policies, VPNs, IPS, and content filtering
• Implement and enforce identity and access security through Azure AD/Entra ID (conditional access, MFA, privileged access management)
• Harden Microsoft 365 and Exchange environments, including email security, anti-phishing, and compliance policies
• Conduct vulnerability management, patching oversight, and security assessments
• Develop, maintain, and test incident response plans and help drive response to security incidents
• Support security awareness, audits, and compliance efforts (e.g., CIS, NIST, SOC 2, or industry-specific frameworks)
• Continuously evaluate and improve the security stack and threat detection capabilities

Network & Infrastructure

• Design, deploy, and maintain multi-site LAN/WAN, cloud, and AWS network infrastructure across five OpCos in multiple states
• Manage site-to-site connectivity, VPNs, and inter-OpCo WAN links
• Configure and manage Cisco switches, including VLANs, STP, and LACP
• Configure and manage routing protocols (BGP, OSPF, EIGRP)
• Manage and maintain the VMware virtual environment (vSphere/ESXi hosts, VMs, resource allocation)
• Administer AWS cloud infrastructure, including VPCs, subnets, security groups, and secure connectivity
• Assist with secure network infrastructure design and buildout for office construction and renovation projects, including cabling, IDF/MDF layout, wireless coverage, and structured cabling standards
• Coordinate with contractors, architects, and vendors on physical network and low-voltage requirements
• Standardize network configurations, security policies, and documentation across all OpCos

Shared Services & Standardization

• Serve as part of a centralized shared services team supporting IT and security across all OpCos
• Drive standardization of IT and security policies, tooling, and configurations across the organization
• Partner with OpCo leadership and local IT staff to align on shared standards while accommodating business-specific needs
• Support onboarding of new acquisitions or OpCos into the standardized environment
• Monitor network performance, conduct capacity planning, and troubleshoot escalated issues
• Travel between OpCos as needed for projects, deployments, and support
• Participate in on-call rotation and respond to critical incidents

Required Qualifications

• 7+ years of hands-on network and systems engineering experience, with a strong cybersecurity focus
• Demonstrated experience with security hardening, threat detection, and incident response
• Experience with Zero Trust security models and ZTNA (ThreatLocker, Zscaler, or comparable allowlisting/endpoint and network access platforms)
• Hands-on experience with MDR/EDR platforms (Huntress, Arctic Wolf, or similar)
• Hands-on experience administering SonicWall firewalls (security policies, VPNs, IPS, filtering)
• Strong identity security experience with Azure AD/Entra ID (conditional access, MFA, PAM)
• Experience securing Microsoft 365 and Exchange (email security, anti-phishing, compliance)
• Working knowledge of Cisco or comparable enterprise switches
• Strong experience managing a VMware virtual environment (vSphere/ESXi)
• Experience administering AWS cloud infrastructure (VPC, EC2, security groups, networking)
• Experience managing multi-site environments across multiple OpCos or states
• Experience designing network infrastructure for office construction, buildouts, or renovations
• Strong knowledge of TCP/IP, DNS, DHCP, BGP, OSPF, and QoS
• Working knowledge of security frameworks (NIST, CIS, SOC 2, or similar)

Soft Skills

• Strong analytical and problem-solving ability under pressure
• Security-first mindset with attention to detail and risk awareness
• Clear communicator who can translate technical and security concepts for non-technical stakeholders
• Self-directed with the ability to manage multiple priorities in a fast-paced environment
• Collaborative team player with a mentorship mindset
• Willingness to travel between OpCos as needed

To Staffing and Recruiting Agencies:  Our company does not accept unsolicited CVs or applications from agencies. We are not responsible for any fees related to unsolicited CVs or applications and explicitly reserve the right to contact candidates presented in such unsolicited CV or application.
 
All applicants who are offered employment with Thayer Power & Communication Line Construction Co., LLC (TPC), will be subject to a background investigation and drug test. Offers of employment are contingent on the successful completion of a background investigation and drug test conducted in accordance with TPC Policy and state law.
 
Our company provides equal employment opportunities (EEO) to all employees and applicants for employment without regard to race, religion, sex, color, national origin, sexual orientation, age, disability, or veteran status. In addition to federal law requirements, TPC complies with applicable state and local laws governing nondiscrimination in employment in every location in which the company has facilities. This policy applies to all terms and conditions of employment, including recruiting, hiring, placement, promotion, termination, layoff, recall, transfer, leaves of absence, compensation, and training.