Senior Application Security Engineer

Senior Application Security Engineer – Policy & Platform

This is a Contract Opportunity with our company that MUST be worked on a W2 Only. No C2C eligibility for this position. Visa Sponsorship is Available! The details are below.

Beware of scams. S3 never asks for money during its onboarding process.

Location: San Antonio, TX or Plano, TX

Work Schedule: Hybrid – 4 Days Onsite / 1 Day Remote

Contract Length: 12 Months

Job Ref #: JOB-248409

Position Summary

Seeking a Senior Application Security Engineer to provide technical expertise across the Application Security platform portfolio.

The AppSec Engineer will support application security tooling, policy implementation, vulnerability analysis, false-positive validation, platform escalations, and developer enablement activities.

Key Responsibilities

• Support Application Security platforms, tooling, and policy implementation.
• Conduct vulnerability analysis, root-cause analysis, and false-positive assessments.
• Support SAST, SCA, API Security, DAST, Infrastructure-as-Code (IaC), and Mobile Security testing.
• Administer and support AppSec platforms and security tooling.
• Provide secure coding guidance and vulnerability remediation support to development teams.
• Support platform escalations and developer enablement activities.
• Work with GitLab, CI/CD pipelines, and DevSecOps practices to support automated security controls.
• Leverage APIs, automation, and AI-assisted workflows to improve security operations.

Required Qualifications

• Deep understanding of Secure SDLC and Application Security practices.
• Hands-on experience with SAST, SCA, API Security, DAST, Infrastructure-as-Code (IaC), and Mobile Security testing.
• Experience administering and supporting AppSec platforms and security tooling.
• Experience conducting vulnerability validation, root-cause analysis, and false-positive assessments.
• Experience providing secure coding guidance and remediation support to development teams.
• Familiarity with GitLab, CI/CD pipelines, DevSecOps practices, and automated security controls.
• Experience leveraging APIs, automation, and AI-assisted workflows to improve security operations.
• Certifications such as CSSLP, CISSP, GWAPT, GWEB, or equivalent industry-recognized credentials.