Security Engineer, Offensive Security

About the Role

As our Security Engineer, Offensive Security, you will own internal offensive testing and lead the move from point-in-time penetration tests to continuous, AI-assisted testing. You will independently plan assessments, safely validate vulnerabilities, work with engineering teams through remediation and retesting, and build sustained knowledge of our source code and systems. You will contribute across application, cloud, and infrastructure security, support Accelerate and MX as priorities change, and share the team's on-call and incident-response work.

Responsibilities

• Independently plan and execute internal penetration tests across applications, APIs, cloud infrastructure, and corporate systems; prioritize assessments by risk and business impact.
• Define testing scope and rules of engagement with system owners, assess production risk, and choose safe methods for validating vulnerabilities.
• Combine hands-on testing with source-code review and architectural analysis to find vulnerabilities and demonstrate realistic attack paths.
• Partner with engineering teams to explain findings, agree on practical fixes, track remediation, and retest to confirm the risk is resolved.
• Maintain knowledge of Liftoff’s systems and attack surface, revisit high-risk attack paths as systems change, and turn confirmed findings into repeatable tests.
• Build testing tools and workflows that combine hands-on assessments with ongoing automated testing and remediation validation.
• Make security testing self-service where practical through reusable tests, documented assessment and retesting workflows, and clear remediation guidance.
• Support the annual third-party penetration test for independent validation and customer and audit requirements; coordinate scope and follow findings through remediation.
• Lead adoption of AI-assisted offensive security tooling: evaluate platforms and build workflows for code analysis, test generation, and finding triage; measure coverage, accuracy, and effort saved.
• Partner with Detection & Response to turn validated attack paths and offensive findings into detection improvements and incident-response exercises.
• Work across application, cloud, and infrastructure security as priorities change, including Accelerate and MX, and share the team’s on-call and incident-response rotation, including occasional off-hours response and post-incident follow-up.

Minimum Qualifications

• 5+ years of relevant security engineering experience, including substantial hands-on penetration testing of applications and infrastructure.
• Excellent judgment in prioritizing testing by risk, assessing production impact, and safely validating exploits without unnecessary disruption.
• Experience independently owning assessments and partnering with engineering teams from initial findings through remediation and retesting.
• Write production-quality code for security tools and automation, review pull requests, and navigate large, unfamiliar codebases. Develop safe proof-of-concept code and independently validate AI-generated code and findings.
• Strong understanding of application and API security, authentication and authorization, network security, and common vulnerability classes.
• Hands-on experience assessing cloud and infrastructure security, including identity and access controls, configuration, and attack paths.
• Ability to quickly understand complex systems and architecture and contribute across application, cloud, and infrastructure security.
• Practical software engineering habits: testing, observability, version control, peer code review, continuous integration, and blameless postmortems.
• Strong technical writing: clear assessment plans, proposals, reproducible findings, runbooks, and post-incident reviews that support engineering decisions. Explain exploitability and business impact clearly in writing and conversation.
• Willingness to share the security team’s on-call and incident-response responsibilities, including occasional off-hours response.

Desirable Qualifications

• Experience with Go, Python, Clojure, or JavaScript; ability to work across languages matters more than a specific language.
• Experience building AI-assisted security testing workflows and measuring the accuracy and usefulness of their results.
• Experience securing large-scale cloud systems, mobile advertising, or other high-volume SaaS environments.