Sr. Application Security Engineer

🛡 Senior Application Security Engineer | United States | Remote

Pax8 is hiring a Senior Application Security Engineer in the United States to help secure the cloud marketplace, financial platforms, and agentic AI products powering our next chapter.

This is application security with real ownership. You'll partner directly with engineering leaders and architects, influence how products are designed and delivered, and combine deep security craft with emerging AI capabilities. The fundamentals matter here: AI is a force multiplier, but great security judgment comes first.

🔐 What you'll get ownership of

• Be a trusted security partner to your product area, working alongside engineering leads and architects to influence secure design and implementation.
• Lead practical threat modeling, helping teams understand where risk lives and turning that insight into actionable engineering decisions.
• Go beyond automated findings with hands-on code review, design review, and security testing that identifies the issues requiring real human judgment.
• Own the vulnerability lifecycle, evaluating findings from static application security testing, software composition analysis, dynamic application security testing, and secret-scanning tools and helping teams prioritize what genuinely matters.
• Make security tooling better, tuning and maintaining security tooling within delivery pipelines and bringing useful security insight directly into developer workflows.
• Build for the AI era, creating agentic tooling that can improve vulnerability triage, deduplication, exploitability enrichment, and remediation guidance while maintaining appropriate human oversight.
• Help secure AI-assisted development, shaping guardrails for AI-assisted and agent-generated code and validating whether those controls work in practice.
• Turn identified vulnerabilities into resolved vulnerabilities, partnering with engineering teams to reproduce issues, shape remediation, and validate fixes.
• Represent security in architectural decisions, clearly explaining technical risk, tradeoffs, and practical paths forward.
• Raise security capability around you, mentoring teammates and engineering security champions while turning recurring defects into focused learning.
• Support penetration-testing findings, bug bounty triage, and security incidents when your application security expertise is needed.

🎯 The impact you'll make

You'll help bring security closer to the engineering teams building Pax8's next generation of products. Your work will make application security more scalable, measurable, and useful to developers while helping the business innovate confidently across established cloud products, new financial technology, and emerging agentic AI capabilities.

You won't simply point out risk. You'll help engineering teams understand it, solve it, and build more securely the next time.

⭐ You'll thrive here if you bring

• Substantial application or product security experience, with a track record of partnering directly with software engineering teams.
• Deep practical capability in threat modeling and manual code review for web and microservice environments.
• Strong understanding of difficult application-security problems such as authorization, multi-tenant isolation, and business-logic vulnerabilities.
• Hands-on experience operating application security tooling for source-code analysis, dependency analysis, dynamic testing, and secret detection, including configuration, tuning, pipeline integration, and finding triage.
• The technical judgment to distinguish a noisy security finding from an exploitable risk and explain the remediation clearly.
• Experience creating automation or engineering tooling for vulnerability management. Applying large language models or agents to security workflows is especially valuable.
• Practical understanding of security risks in large language model and agentic applications, including prompt injection, unauthorized tool use, and potential data-exfiltration paths.
• Proficiency with at least one modern cloud-native programming language. Our environment includes Kotlin and JavaScript/TypeScript, and you should be comfortable reading unfamiliar code.
• Working knowledge of Amazon Web Services, Kubernetes, containers, and infrastructure as code.
• Bonus depth in securing agentic applications, Model Context Protocol integrations, identity and authorization in multi-tenant software-as-a-service environments, or transactional and financial systems.
• The confidence to challenge a design constructively, explain the tradeoff, and work with engineers toward a solution rather than simply raising a blocker.

💰 Compensation & benefits

Compensation Range: $140,000 - $160,000

Application Deadline: November 30, 2026

At Pax8 we believe that your Total Rewards should include a benefits package that shows how much we value our greatest assets. All FTE Pax8 people enjoy the following benefits:

• 401(k) with Company Match
• Medical, Dental & Vision Coverage
• Employee Assistance Program (EAP)
• Employer-Paid Life, AD&D, Short-Term Disability & Long-Term Disability Insurance
• Flexible Open PTO
• Paid Sick Leave
• Paid Parental Leave
• RTD EcoPass (eligible Colorado-based employees)

📈 What's in it for you?

There's extensive room for a talented individual to grow at pace - whether that's advancing quickly in this role or exploring one of the many opportunities across our global organisation. You'll have access to our internal development hub designed to accelerate your skills and stretch your potential. Alongside specialist Learning & Development trainers, you'll also tap into AI powered tools, "born in the cloud" mentors, and cross continent collaboration that broaden your perspective and sharpen your expertise. We'll give you the space, trust, and the right projects to help you thrive - and full visibility of what it takes to reach your next level.