Senior Security Tester Jobs (NOW HIRING)

About Medical Guardian:

Medical Guardian is a fast-growing digital health and safety company on a mission to help people live a life without limits. With 13 consecutive years on the Inc. 5000 list of Fastest Growing Companies, we’re redefining what it means to age confidently and independently.

We support over 625,000 members nationwide with life-saving emergency response systems and remote patient monitoring solutions. Trusted by families, healthcare providers, and care managers, our work is powered by a culture of innovation, compassion, and purpose.

Position Summary:

We are seeking a highly skilled and strategic Senior Security Engineer to strengthen and mature our enterprise security capabilities as part of the broader IT Operations organization. This role is responsible for securing cloud infrastructure, AI platforms, applications, endpoints, identity systems, and core operational environments.

The Senior Security Engineer will work closely with Infrastructure, Engineering, Compliance, QA, IT Operations, and external security service providers to proactively reduce risk while enabling business growth. This position reports directly to the Head of Infrastructure and Information Security, with a dotted-line reporting relationship to the CISO for strategic alignment, governance oversight, and security program direction.

This role serves as the primary technical lead for security incident response, responsible for coordinating internal response teams, activating third-party incident response partners when required, and leading containment and recovery efforts during active security events. The position requires the ability to respond to and manage security incidents outside of standard business hours when necessary.

This is a hands-on senior engineering role with architectural ownership, external partner oversight, and mentorship responsibilities.

Key Responsibilities:

Security Architecture and Engineering

• Design and implement secure architecture patterns across Azure and AWS cloud environments, as well as on-prem and hybrid infrastructures

• Lead security design reviews for infrastructure and application initiatives

• Engineer and optimize enterprise security controls across endpoint protection, threat detection and response, network security, email security, data protection, cloud access governance, and privileged access management

• Define and implement Zero Trust principles

Cloud Security, Azure Focused

• Harden Azure security posture including Entra ID governance, RBAC design, Conditional Access, PIM, Defender for Cloud, Defender for Cloud Apps, and Private Link architecture

• Implement and manage cloud posture management and cloud workload protection capabilities, including CSPM and CNAPP tooling

• Secure Kubernetes and containerized workloads

• Automate security guardrails using infrastructure as code such as Terraform, Bicep, and CloudFormation

• Implement enterprise data classification, DLP, encryption, and tenant-level controls across Microsoft 365 and Azure to prevent data exfiltration and unauthorized AI service access

AI and Emerging Technology Security

• Design, implement, and enforce security controls for enterprise AI platforms including Azure OpenAI, Microsoft Copilot, Azure Machine Learning, and related AI services

• Secure AI model training data, inference endpoints, APIs, and service principals while enforcing governance controls to prevent exposure of sensitive or regulated data

• Develop guardrails to detect and prevent shadow AI adoption

• Evaluate third-party AI tools for security, privacy, and data residency risks

• Partner with Legal and Compliance teams to support responsible AI governance and regulatory requirements

Application Security

• Partner with DevOps and Engineering teams to integrate automated application security testing, including static analysis, dynamic testing, and secret detection, into CI and CD pipelines prior to deployment

• Perform threat modeling and architecture risk assessments

Threat Detection and Incident Response

• Serve as incident response lead for security events, coordinating internal response teams and activating third-party incident response partners as needed

• Lead containment, eradication, and recovery efforts during security incidents

• Enhance detection engineering use cases within SIEM and develop automated response playbooks

• Lead post-incident reviews and root cause analysis

• Lead and facilitate regular incident response tabletop exercises and coordinated response simulations to validate detection, escalation, and cross-functional readiness

Vulnerability Management

• Oversee enterprise vulnerability management including scanning, risk-based prioritization, and remediation tracking

• Develop metrics and reporting for executive visibility

Compliance and Risk

• Support regulatory requirements including HIPAA, HITRUST, SOC 2, and PCI-DSS as applicable

• Assist with audits and evidence collection

• Develop and maintain security policies and standards

• Perform third-party risk assessments

Security Operations and External Partner Management

• Oversee MDR detection coverage, alert tuning, escalation workflows, service level adherence, and integration of logging and telemetry between internal systems and third-party providers

• Collaborate with the MSP on infrastructure security hardening, patching strategy, endpoint protection, and configuration management

• Drive continuous improvement through regular performance reviews and security posture assessments with external partners

Leadership and Mentorship

• Provide technical guidance and drive security best practices across IT and Engineering initiatives

• Serve as escalation point for complex security issues

Requirements

Required Qualifications

• Must be legally authorized to work in the United States without the need for employer sponsorship now or in the future
• 5 or more years of progressive experience in cybersecurity engineering

• Strong experience in Azure security architecture and hands-on implementation of controls including Entra ID, Conditional Access, PIM, Defender for Cloud, and Private Endpoints

• Deep understanding of network security, identity and access architecture, endpoint protection, and security monitoring and detection engineering principles

• Experience securing AI and ML platforms or cloud-native AI services

• Experience implementing enterprise data protection controls including DLP, Purview, labeling, encryption, and key management

• Experience with infrastructure as code and automation using Python, PowerShell, Terraform, Bicep, or similar tools

• Experience securing CI and CD pipelines and containerized environments

• Strong knowledge of security frameworks including NIST, CIS, and ISO 27001

• Experience managing third-party security operations relationships and holding vendors accountable to defined service levels

Preferred Qualifications

• Experience in regulated industries such as healthcare

• Experience implementing Zero Trust architectures

• Security certifications such as CISSP or CCSP strongly preferred. Azure security certifications including AZ-500 highly valued. GIAC certifications such as GCED or GCIA and OSCP are considered a plus.

Work Environment & Requirements:

• Hybrid work model with on-site presence required two days per week at the Philadelphia location

• Serve as the primary incident response lead, including availability outside standard business hours to coordinate and manage security incidents and engage third-party incident response partners when necessary
• Candidates must be authorized to work in the United States without current or future need for visa sponsorship.

Benefits

• Health Care Plan (Medical, Dental & Vision)
• Paid Time Off (Vacation, Sick Time Off & Holidays)
• Company Paid Short Term Disability and Life Insurance
• Retirement Plan (401k) with Company Match