Principal Application Security Engineer

Job Summary

Join CDW and help secure the software, platforms, and services that support more than 250,000 customers across enterprise, government, education, and healthcare. As part of CDW ’s Global Information Security team, you will help shape how application security is embedded into engineering at scale—partnering across development, platform engineering, SRE, and DevOps to reduce risk while enabling delivery.

As a Principal Application Security Engineer, you will serve as a senior technical leader and trusted advisor who helps influence secure engineering practices across the enterprise. You will bring deep hands-on application security expertise while enabling teams to adopt scalable patterns, controls, and guardrails across applications, APIs, and software delivery pipelines. This role is ideal for someone who can move fluidly between strategy and execution—shaping direction, building trust through influence, and diving into technical detail when needed.
What you will do
- Lead high-impact secure code reviews, threat models, and secure design assessments for applications, APIs, and shared services—translating technical risk into clear guidance for engineers, technical leaders, and business stakeholders.

- Drive the design, integration, and continuous improvement of application security controls across CI/CD platforms, workflows, and environments in close partnership with engineering, DevOps, and platform teams.

- Identify control gaps, coverage weaknesses, and sources of engineering friction across the software delivery lifecycle, and drive practical remediation through automation, platform improvements, and secure-by-design patterns.

- Define, advocate for, and build secure coding standards, reference architectures, playbooks, tooling, and automations that scale application security without slowing delivery.

- Serve as a senior technical partner to engineering teams by influencing design decisions, guiding remediation strategy, and helping embed security into how software is built and deployed.

- Advance CDW ’s approach to securing AI-enabled development and applications by evaluating emerging risks, defining practical guardrails, and promoting responsible use of AI as a force multiplier for engineering and security outcomes.

- Provide deep subject matter expertise in API security, including authentication and authorization models, protections, monitoring, and secure integration patterns across modern application ecosystems.

- Partner with web and platform teams to design, deploy, and tune application-layer protections such as WAF rules and policies.

What we expect of you
- 10+ years of experience in Application Security Engineering, including hands-on work embedding security into software design, development, and delivery practices.

- Deep, hands-on expertise in secure application architecture and design, secure coding practices, code-level vulnerability analysis, and threat modeling.

- Background in software engineering, application development, or architecture, with the ability to engage credibly at the design, code, build, or runtime levels.

- Strong command of authentication, authorization, session management, API security, secrets management, and common application vulnerabilities and exploit patterns, including OWASP Top 10 classes, injection, deserialization, SSRF, insecure design, access control issues, and dependency risk.

- Hands-on experience securing applications built in one or more modern technology stacks such as C#, Java, Python, JavaScript or TypeScript, Go, or similar.

- Strong experience integrating security into CI/CD pipelines, developer workflows, and engineering platforms, including technologies such as SAST, SCA, DAST, IaC scanning, container security, API security testing, and software supply chain security controls.

- Ability to independently investigate complex technical problems, identify root causes, and drive practical remediation while mov