Senior AppSec Engineer — End-to-End Security Leader

Better Tomorrow Ventures; Toronto; On-site; CAD 180,000 - 220,000; Full time

Job summary

Relay is seeking a Senior Application Security Engineer II in Toronto to own end-to-end security for critical services, from design to deployment. You will work across TypeScript/Node.js, Postgres, and AWS to identify risks, build guardrails, and advance our security practices as Relay scales.

You will collaborate with senior engineers, mentor teammates, and drive security testing and remediation across multiple teams using modern tooling and AI-assisted approaches.

Qualifications

• 5 to 6 years of professional security experience.
• Shipped production code on production systems.
• Deep understanding of OWASP Top 10 and mitigation techniques.
• Experience building with AI tooling and understanding its limits.
• Strong communication and collaboration with developers.
• Ownership mindset and proactive problem solving.
• Mentorship of team members on security best practices.

Responsibilities

• Threat modeling and white-box testing across the stack.
• Triage researcher reports, assess impact, coordinate fixes.
• Contribute patches to Relay's codebase when appropriate.
• Work with security tooling (Datadog, Burp Suite) and in-house tools.
• Leverage AI tools as daily drivers in security workflows.
• Participate in standups, security champions sessions, and Hack The Box.
• Enforce SBOM, dependency pinning, private registries, and SBOM provenance.

Skills

Application security

Penetration testing

Product security engineering

AI in security

Communication & collaboration

Ownership

Mentorship

Tools

Burp Suite

Datadog Security

Secrets scanning

Job description

Relay is seeking a Senior Application Security Engineer II in Toronto to own end-to-end security for critical services, from design to deployment. You will work across TypeScript/Node.js, Postgres, and AWS to identify risks, build guardrails, and advance our security practices as Relay scales.

You will collaborate with senior engineers, mentor teammates, and drive security testing and remediation across multiple teams using modern tooling and AI-assisted approaches.