Senior Security Engineer

Arch Capital Group Ltd. is seeking a Senior Security Engineer to safeguard its enterprise systems, data, and cloud environments by applying advanced security engineering, threat detection, and AI-enabled capabilities. The role leads complex investigations and enhances detection and response through automation and AI.

Overview

This position focuses on protecting corporate assets across on premises and cloud infrastructure, leveraging sophisticated security engineering, proactive threat hunting, and AI driven security solutions. The Senior Security Engineer serves as a senior technical resource, guiding investigations and elevating detection and response through automation and AI enhancements.

Responsibilities

• Design and deploy agentic AI workflows and autonomous playbooks to automate Tier 1 and 2 alert triage, enrich context, and drive incident response.
• Develop and fine tune complex detection logic across SIEM, EDR/XDR, and cloud platforms with an emphasis on behavioral analytics and anomaly detection.
• Utilize Python to create custom security tools, integrate diverse security APIs, and maintain clean, reusable codebases for security orchestration (SOAR).
• Lead threat hunting programs and act as a Tier-3 escalation resource for high-severity security incidents.
• Analyze attacker tactics, techniques, and procedures to align coverage with the MITRE ATT&CK framework and proactively close gaps.
• Secure cloud environments including AWS, Azure, or GCP, focusing on auditing, monitoring, and protecting production AI and LLM pipelines and workloads.
• Mentor junior team members, perform code reviews for automation scripts, and promote robust software engineering practices within the security group.

Requirements

• At least seven years of cybersecurity experience with a focus on security or detection engineering.
• A minimum of three years in a senior security engineering role.
• Strong technical knowledge of incident response, threat hunting, and adversary TTPs.
• Experience implementing and managing detection logic across enterprise SIEM, EDR/XDR, or cloud-native security tools.
• Experience securing and monitoring cloud infrastructure (AWS, Azure, or GCP).
• Proven ability to build functional tools in Python and PowerShell, interact with REST APIs, and maintain clean, structured code; familiarity with Git and CI/CD pipelines is preferred.
• Bachelor’s degree in Computer Science, Cybersecurity, or Engineering.

Technologies

• Python
• PowerShell
• REST APIs
• Git
• CI/CD pipelines
• AWS
• Azure
• GCP
• SOAR
• SIEM
• EDR/XDR
• MITRE ATT&CK
• AI/LLM pipelines

Benefits

• Medical plans including dental, vision, and prescription drug coverage
• 401(k) with generous matching
• PTO starting at 20 days per year
• Up to 12 paid company holidays annually
• 2 paid days of Volunteer Time Off
• Basic Life and AD&D Insurance
• Short and Long-Term Disability
• Paid Parental Leave up to 10 weeks
• Student Loan Assistance and Tuition Reimbursement
• Backup Child and Elder Care

Why This Role

The position offers a path to shape next generation security capabilities, including AI driven detection, automation, and cloud security, while tackling high impact enterprise challenges. It is a remote role that can be located anywhere in the United States, with proximity to Arch offices preferred.

Preferred

• Practical understanding of building or implementing LLM based agents, prompt engineering, and integrating AI models into automated workflows and custom API integrations.
• Familiarity with AI and LLM security vulnerabilities such as prompt injection, data poisoning, and model evasion.
• Experience with SIEM, EDR/XDR, SOAR, or identity security platforms.
• Advanced certifications such as CISSP, GIAC GCIA/GCIH, or cloud security certifications.
• Master's degree in Computer Science, Cybersecurity, or IT Management with an emphasis on AI and automation.