Senior AppSec Engineer: Tooling & Threat Modeling Lead

The Trade Desk; Seattle (WA); On-site; USD 125,000 - 208,100; Full time

Job summary

The Trade Desk in Seattle is seeking a Senior Application Security Engineer to join our Cybersecurity Department. You will own tooling, lead threat modeling, and harden the application security program across a platform used daily by global brands.

You will write production-grade security automation, review features, APIs, and code, and drive secure-by-design patterns with engineers. A deep background in app security, software development, and collaboration is essential in our fast-moving,

Qualifications

• 6-8+ years in application security with tooling and automation.
• Hands-on development experience in one or more languages.
• Strong experience with SAST/DAST/SCAs and secrets management.
• Experience in threat modeling and vulnerability management workflows.
• Familiarity with Kubernetes and cloud security fundamentals.

Responsibilities

• Extend and own scalable AppSec tooling across core areas.
• Contextualize risk for engineering teams and customers.
• Conduct security-focused reviews of features, APIs, and code.
• Write production-grade security automation and tooling.
• Assess and secure AI/ML systems and GenAI surfaces.
• Drive secure-by-design practices and governance frameworks.
• Collaborate with engineers to raise the security floor.

Skills

Application security tooling

Threat modeling

CI/CD integration

Software development

Vulnerability management

Kubernetes & containers

Cloud security (AWS/GCP/Azure)

AI/ML security

Communication

Security certifications (OSWE/GWAPT/CY

Education

BS degree or equivalent

Tools

Docker

Helm

Istio

GitHub Actions

Job description

The Trade Desk in Seattle is seeking a Senior Application Security Engineer to join our Cybersecurity Department. You will own tooling, lead threat modeling, and harden the application security program across a platform used daily by global brands.

You will write production-grade security automation, review features, APIs, and code, and drive secure-by-design patterns with engineers. A deep background in app security, software development, and collaboration is essential in our fast-moving,