Senior Security Engineer

Signal 1 • Toronto, ON

90d • Hybrid

About The Position

Signal 1 helps health systems accelerate AI adoption with a category defining technology platform. Signal 1’s first product, the AI Management System (AIMS), gives health system leaders visibility and control across their growing AI portfolios. AIMS offers comprehensive oversight of predictive and generative AI applications and introduces guardrails to mitigate downside risks. It sets the standard for Responsible AI in healthcare. Purpose-built for healthcare and informed by years of experience managing AI at scale in other industries, Signal 1 empowers healthcare organizations to translate innovation into real clinical, operational, and financial outcomes.
Signal 1 is a 30-person, well-funded and rapidly growing startup with strong product market fit and deployments at a growing number of top-20 US health systems.

We are looking for a Senior Security Engineer to join our Engineering Team. You will:
Support end-to-end security architecture across all domains (IAM, infrastructure security, application security, cyber defense, and data security), ensuring controls are consistent, defensible, and right-sized for a fast-moving healthcare AI platform.
Design and implement Azure-native security solutions using the full Microsoft security stack: Entra ID, Defender for Cloud, Microsoft Sentinel, Defender for Endpoint, Purview, and Azure Policy, across both fully cloud-based and hybrid infrastructure environments.
Support and collaborate on GRC programs across the full compliance lifecycle, contributing to control mapping, evidence collection, and audit readiness for SOC 2 Type II, HIPAA, and potentially other frameworks as the business evolves.
Partner with Engineering, ML, and Infrastructure teams to embed security throughout the SDLC, from threat modeling and architecture review through to CI/CD pipeline hardening, secrets management, and production monitoring.
Build and operationalize security monitoring, alerting, and incident response capabilities, identifying detection gaps and closing them with tooling, process, and cross-team coordination.
Champion product security across the AIMS platform, conducting security design reviews, threat modeling, and vulnerability assessments on new and existing features, and working closely with product and engineering teams to ensure security is built in from the start, not bolted on.
Bring an open mindset to the role, willing to roll up your sleeves and contribute to broader engineering and infrastructure initiatives outside of pure security work when the team needs it.

Requirements

• Bachelor’s degree in computer science/engineering or equivalent practical experience.
• 5+ years of experience in security engineering, with deep, hands-on expertise in Microsoft Azure security architecture and the Microsoft security product ecosystem.
• Technically strong across all security domains (IAM, infrastructure, application security, cyber defense, and data protection), with the architectural depth to design solutions from first principles, not just operate existing ones.
• You see the big picture. You understand how security decisions affect product velocity, customer trust, and business outcomes, and you can translate technical risk into language that resonates with executives, customers, and cross-functional partners.
• Comfortable securing both fully cloud-native and hybrid environments, with a strong understanding of the trust boundaries and control differences between the two.
• Experienced operating in highly regulated environments, with direct involvement in SOC 2 Type II, HIPAA, or equivalent compliance programs.
• You thrive in fast-paced, high-ambiguity environments. You can triage competing priorities, move quickly without cutting corners, and build durable solutions under startup constraints.
• Proactive and curious by nature. You don’t wait to be pointed at problems, you go looking for them, and you bring genuine enthusiasm for learning new domains, tools, and threat landscapes.
• Strong communication skills with the ability to engage engineering teams, executive stakeholders, and external customers including hospital security and compliance teams.

Nice To Haves

• Relevant certifications: CISSP, AZ-500 (Azure Security Engineer), or OSCP.
• Fluent with AI coding and productivity tools, using them as a force multiplier in your daily work, not as an afterthought.
• Experience with Kubernetes security, infrastructure-as-code (Terraform/Bicep), and securing CI/CD pipelines in Azure DevOps or GitHub Actions.
• Familiarity with healthcare data standards and regulations (HIPAA, PHIPA) or prior experience securing systems in healthcare, finance, or other regulated industries.
• Exposure to AI/ML security considerations (model access controls, data pipeline integrity, LLM threat surfaces, or agent security) is a strong plus.

Responsibilities

• Support end-to-end security architecture across all domains (IAM, infrastructure security, application security, cyber defense, and data security), ensuring controls are consistent, defensible, and right-sized for a fast-moving healthcare AI platform.
• Design and implement Azure-native security solutions using the full Microsoft security stack: Entra ID, Defender for Cloud, Microsoft Sentinel, Defender for Endpoint, Purview, and Azure Policy, across both fully cloud-based and hybrid infrastructure environments.
• Support and collaborate on GRC programs across the full compliance lifecycle, contributing to control mapping, evidence collection, and audit readiness for SOC 2 Type II, HIPAA, and potentially other frameworks as the business evolves.
• Partner with Engineering, ML, and Infrastructure teams to embed security throughout the SDLC, from threat modeling and architecture review through to CI/CD pipeline hardening, secrets management, and production monitoring.
• Build and operationalize security monitoring, alerting, and incident response capabilities, identifying detection gaps and closing them with tooling, process, and cross-team coordination.
• Champion product security across the AIMS platform, conducting security design reviews, threat modeling, and vulnerability assessments on new and existing features, and working closely with product and engineering teams to ensure security is built in from the start, not bolted on.
• Bring an open mindset to the role, willing to roll up your sleeves and contribute to broader engineering and infrastructure initiatives outside of pure security work when the team needs it.

What This Job Offers

• Job Type: Full-time
• Career Level: Mid Level
• Number of Employees: 1-10 employees