App Security Expert

Confidential; United States; Remote; USD 120,000 - 180,000; Part time

Job summary

Zekai is seeking an App Security Expert on a 100% remote contract basis. You will design fixtures with embedded vulnerabilities or secure solutions, craft deterministic tests, and generate hidden keys for evaluation of secure vs vulnerable code. Collaboration will span documenting methods and sharing findings with teams worldwide.

The role emphasizes strong writing, security architecture experience, and the ability to deliver actionable recommendations in a remote setting.

Qualifications

• Extensive experience in application security or CyberSWE roles.
• Strong understanding of OSWE, LLM security, AI-SAST, and AppSec best practices.
• Proven track record in designing or evaluating security architecture for traditional and agent-based apps.
• Expertise in building, securing, and testing application codebases for vulnerabilities.
• Excellent written and verbal communication with precise technical documentation.
• Experience with synthetic security fixtures and deterministic testing approaches.
• Ability to deliver actionable security recommendations remotely.

Responsibilities

• Design and implement small, purpose-built app fixtures with vulnerabilities or secure solutions.
• Develop deterministic test cases and security-context manifests to assess posture.
• Create hidden answer keys for AI or scanner evaluation of secure vs vulnerable code.
• Evaluate and iterate on pipelines to keep tasks challenging yet realistic.
• Document technical insights and methodologies clearly.
• Collaborate through precise written and verbal communication to share findings.
• Engage with agent-based security architecture and improve the evaluation pipeline.

Skills

Application security

Secure software development

OSWE

LLM security

AI-SAST

Security architecture

Security testing

Communication skills

Synthetic fixtures

Remote collaboration

Tools

Static analysis tools

AI-powered analysis

Job description

Role Title: App Security Expert

Role Type: Contractor

Location: Remote

our partner is engaging App Security Experts to contribute to a customer’s dynamic project focused on real-world application security. In this role, you'll apply your expertise to help train next-generation AI systems. Your work will shape how models learn, reason, and perform through high-quality, real-world input. No prior experience in AI is required — your domain knowledge is what matters.

Scope of Work

• Design and implement small, purpose-built application fixtures with embedded security vulnerabilities or secure solutions, specifically addressing OWASP LLM risks such as Sensitive Information Disclosure and Excessive Agency.
• Develop deterministic test cases and security-context manifests to robustly assess application security posture.
• Create detailed hidden answer keys to enable accurate AI or scanner evaluation of vulnerable versus secure code.
• Evaluate and iterate on pipeline methodologies to ensure synthetic tasks and fixtures are challenging yet realistic for AppSec assessment.
• Document technical insights and methodologies, ensuring clarity in written feedback and communication.
• Collaborate through clear and thorough written and verbal communication to share findings and review peer contributions.
• Engage with agent-based security architecture and contribute to continuous improvement of the evaluation pipeline.

Preferred Qualifications

• Extensive experience (ideally 5+ years) in application security, secure software development, or CyberSWE roles.
• Strong understanding of OSWE, LLM security, AI-powered static analysis (AI-SAST), and AppSec best practices.
• Proven track record designing or evaluating security architecture for traditional and agent-based applications.
• Expertise in building, securing, and testing application codebases, including identifying and remediating advanced vulnerabilities.
• Exceptional written and verbal communication skills, with a focus on precise technical documentation and collaborative feedback.
• Experience with synthetic security fixtures and deterministic testing approaches is highly desirable.
• Demonstrated ability to deliver thoughtful insights and actionable security recommendations in a remote contribution context.

This is a 100% remote contract role, open to applicants worldwide in the countries the employer accepts.