Senior Application Security Engineer

The Senior Application Security Engineer II is a senior individual contributor responsible for strengthening Apollo’s secure software development lifecycle and reducing application risk across product platform and AI-powered features.

This role blends deep code-level application security work with strong cross-functional partnership. It includes application security reviews threat modeling AppSec tooling findings triage and remediation follow-through external testing intake and developer enablement.

This role is calibrated at the L6 senior-IC level: owning semi-annual or annual goals solving ambiguous problems with sound judgment improving operational processes and driving meaningful cross-team collaboration and influence.

• Own and continuously improve the secure software development lifecycle for Apollo applications so security is embedded into design implementation and deployment.
• Perform application security reviews threat modeling and deep code-level analysis for high-impact product platform and AI features before launch.
• Provide practical security architecture guidance to Engineering Product and IT teams.
• Help define and maintain application-security guardrails secure design expectations code review standards and risk models for new and existing systems.

• Drive execution-heavy vulnerability management across internal reviews bug bounty pentests SCA/runtime findings and other research signals ensuring findings are validated prioritized routed clearly and tracked through remediation and verification within SLAs.
• Go beyond identifying issues: read the code explain root cause propose the safest fix and directly implement or support remediation when needed for complex vulnerabilities.
• Perform hands-on validation and offensive security testing of applications and fixes including exploit development bypass testing adversarial thinking and focused red-team-style exercises to confirm remediations address the underlying issue rather than only the initial symptom.
• Work across the kinds of application security issues common in modern SaaS environments including authentication and authorization weaknesses access control risks OAuth and CSRF design flaws SSRF cryptographic and verification issues information disclosure and data exposure risks unsafe execution and deserialization patterns and dependency or runtime vulnerabilities.
• Apply clear risk-based severity decisions using exploitability data sensitivity customer impact and blast radius.

• Configure and improve AppSec tooling and integrations including SAST configuration ignore lists dashboards and other controls that maintain useful coverage without excessive noise.
• Select build or refine security tooling small automations and workflow enrichments that reduce manual effort and scale AppSec operations responsibly.
• Use AI to automate transform and scale security and engineering-adjacent processes where it materially improves speed consistency or signal quality while still validating outputs with strong engineering judgment.
• Embed AI-specific security checks into SSDLC reviews and code analysis including input and output handling AI-exposed APIs prompt and response guardrails and abuse or data-exfiltration paths.
• Partner cross-functionally on AI security requirements and controls so AI systems and AI-powered features are designed deployed and operated securely.

• Support and scale security enablement for engineers and security champions including secure coding AppSec and AI-safety content.
• Provide actionable remediation guidance secure patterns and examples that help engineering teams fix issues quickly and correctly.
• Partner closely with Engineering Product Platform Data Legal and other security teams to keep AppSec priorities aligned with business risk and product velocity.
• Produce clear documentation metrics and written narratives that improve AppSec visibility observability and decision-making.

• Owns meaningful AppSec goals over a semi-annual or annual horizon and independently identifies the right solutions to ambiguous open-ended problems.
• Drives cross-team collaboration and operational improvements beyond isolated tickets or one-off reviews.
• Makes informed decisions by balancing technical detail business context customer trust and long-term risk.
• Sets a high bar for ownership communication mentoring and technical judgment and helps raise the effectiveness of peers and partner teams.

• 5+ years of software engineering or application security experience with meaningful hands-on AppSec depth in modern SaaS environments.
• Strong software development skills and the ability to read write and ship production code; Ruby experience is highly valuable and Python or similar scripting ability is a plus.
• Strong Linux and cloud fundamentals ideally with experience in GCP-backed environments.
• Deep familiarity with common AppSec issues secure design secure authentication and authorization patterns vulnerability management and developer security tooling.
• Demonstrated ability to perform deep code review penetration testing and exploit-oriented validation and to either fix vulnerabilities directly or work closely with engineers to land durable remediations that hold up against bypass attempts and variant analysis.
• Experience handling findings from bug bounty pentests internal reviews or automated security tooling through closure and verification.
• Experience using AI-assisted tools automations APIs or structured workflows to improve engineering or security processes at scale.
• Experience securing AI-powered systems or features including AI API exposure prompt and response handling data protection misuse scenarios and monitoring expectations.
• Strong written and verbal communication stakeholder management and influencing skills across technical and non-technical partners.

• Experience supporting or leading security reviews for AI-native products internal agents or AI-assisted engineering workflows.
• Experience improving secure-by-design practices and AppSec observability in a fast-moving engineering organization.
• Experience with security training developer enablement or security champions programs.
• Relevant security certifications are a plus.

• • Improve the health and flow of AppSec findings by keeping prioritization remediation and verification moving within defined SLAs.
  • Complete recurring application reviews or threat models for important systems and features.
  • Increase engineering adoption of secure patterns AppSec tooling and security training.
  • Reduce manual toil and improve AppSec signal quality through targeted automation and responsible use of AI-assisted workflows.

What We Do

Apollo is a $1.6B AI-powered sales platform that helps revenue teams find and engage leads automate outreach manage deals and enrich data — all in one place. Known for its industry-leading B2B database of more than 210 million contacts and 35 million companies Apollo’s end-to-end platform helps businesses of all sizes unlock their full market potential with unparalleled precision and ease. Trusted by 500000+ companies including Autodesk Cyera and DocuSign Apollo is building the number one go-to-market platform to make the sales process intelligent turnkey and accessible for all. Visit [apollo.io](http://apollo.io/) to learn more.

Why Work With Us

Apollo is building the #1 AI-powered go-to-market platform trusted by 500000+ companies. We move fast invest in our people and promote from within. You'll work on meaningful problems with a curious driven team that values ownership growth and impact. Join us and help shape the future of sales.

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