Senior AppSec Engineer: Build Security Tools & AI Safeguards

The Trade Desk; Ventura (CA); On-site; USD 113,500 - 208,100; Full time

Benefits offered by this job

Healthcare benefits (medical, dental,视

401(k) with company match

Stock-based compensation plan

Job summary

The Trade Desk is seeking a Senior Application Security Engineer to join our Cybersecurity Department. You will own and extend AppSec tooling across SAST/DAST, vulnerability management, threat modeling, and security posture for a platform used daily by major brands.

You will bring deep application security expertise, strong software development instincts, and a bias to action—communicating security requirements effectively to engineers and product leadership.

Qualifications

• 6-8+ years in application security with tooling and automation.
• Active software development experience in at least one language (C#, Java, Python, Go, or JavaScript).
• Experience with SAST/DAST/SC S and secrets management tooling and CI/CD integration.
• Threat modeling (STRIDE/PASTA) producing engineering-useful outputs.
• Experience with vulnerability management workflows and remediation at scale.
• Knowledge of cloud security fundamentals (AWS/GCP/Azure) and container security.

Responsibilities

• Extend and own scalable AppSec tooling across SAST/DAST, vulnerability management, threat modeling, and security posture.
• Validate findings end-to-end: triage and reproduce scanner output and contextualize risk for engineers.
• Review features, APIs, and architecture; conduct security-focused code reviews and app-layer pen tests.
• Write production-grade security automation and tooling, shipping code with security guidance.
• Assess and secure AI/ML systems including GenAI attack surfaces and AI-augmented tooling.
• Drive security culture by partnering with engineers and advocating secure-by-design practices.
• Participate in governance: publishing standards, guidelines, and secure baselines.

Skills

AppSec tooling

Threat modeling

Code review (C#/Java/JS)

Security automation

Cloud security

AI/ML security

Security communication

Incident response mindset

Education

BS degree or equivalent

Tools

GitHub Actions

GitLab

Jenkins

ArgoCD

Kubernetes

Docker

Job description

The Trade Desk is seeking a Senior Application Security Engineer to join our Cybersecurity Department. You will own and extend AppSec tooling across SAST/DAST, vulnerability management, threat modeling, and security posture for a platform used daily by major brands.

You will bring deep application security expertise, strong software development instincts, and a bias to action—communicating security requirements effectively to engineers and product leadership.