US Mobile

US Mobile

Lead Security Engineer (Fraud)

Montreal / Toronto

Sponsorship not specifiedCAD 150k-CAD 220kDetected 107 days ago
JavaKotlinBackend DevelopmentCode ReviewAWSGCPCI/CDDatadogDevOpsMachine LearningCybersecuritySIEMDetection EngineeringIncident ResponseComplianceFirewall5G/LTEZero TrustResearchCommunication

About the role

  • Imagine a world where you can go into a single app and buy terabytes of data for every one of your devices: phone, smart devices, car, home broadband, and more.
  • Our team spans diverse backgrounds, cultures, and stories, with employees coming from 20+ countries.

Responsibilities

  • Hands-on expertise building fraud detection systems for e-commerce and subscription billing environments, including rule-based and ML-assisted models that flag suspicious payment behavior, account-funded fraud, and promo/credit abuse in real time.
  • Perform secure code reviews and guide developers on secure design patterns, embedding fraud-aware coding standards into engineering workflows from the ground up.
  • Build and automate security tooling that integrates into CI/CD pipelines for vulnerability scanning, dependency management, and code integrity checks - including controls specific to payment and billing service deployments.
  • Collaborate with DevOps and backend engineers to design secure architectures, enforce least privilege, and adopt zero-trust principles across subscriber lifecycle flows including onboarding, SIM activation, number porting, and payment processing.
  • Lead threat modeling, risk assessments, and incident response for fraud and security events - maintaining playbooks, coordinating responses, and translating findings into actionable hardening improvements across Telecom-specific attack surfaces.
  • Excellent communication skills and the ability to collaborate with both engineers and leadership.
  • As the Lead Security Engineer, you'll be both a hands-on technical contributor and a security leader.
  • You will write and review code, design secure systems, and work closely with backend and platform engineers to ensure that our infrastructure, applications, and services are resilient against evolving threats.
  • You'll lead a small, high-impact team responsible for embedding security into the entire SDLC - from code review and threat modeling to runtime monitoring and incident response.

Nice to have

  • Bachelor's degree in Computer Science, Software Engineering, or a related field.
  • 7+ years of experience in fraud, cybersecurity, application security, or security engineering - ideally in developer-heavy environments.
  • Strong software engineering background with hands-on experience in Java, Kotlin, or Go (comfortable reading and writing production code).
  • Deep understanding of secure software development, API security, and microservices architectures.
  • Experience integrating security into CI/CD pipelines and cloud-native environments (AWS, GCP, or similar).Understanding of compliance frameworks such as PCI-DSS, SOC 2, or ISO 27001 is a strong plus.
  • Familiarity with observability and monitoring platforms such as Datadog, Cloudflare WAF, or similar tools for traffic analysis and anomaly detection.
  • Proficiency with security monitoring and automation tools (SIEM, EDR, IDS/IPS, etc.).
  • Certifications like CISSP, OSWE, GCSA, or CISM are a plus but not required - demonstrable coding and analytical ability matter most.

Compensation

  • CAD 150k-CAD 220k

Company info

  • At the core of it all, we have a team and culture that has been recognized by Forbes as one of the top 500 best startup employers in the US.
  • We're a venture-backed company entering hypergrowth, having recently ranked 94th on Inc 5000's fastest-growing private companies in America, and we're looking for someone exceptional to join our team.

This listing is sourced directly from US Mobile's careers page and normalized into a canonical job model.