Security Engineer, Offensive Security

Liftoff is a leading AI-powered performance marketing platform for the mobile app economy. Our end-to-end technology stack helps app marketers acquire and retain high-value users, while enabling publishers to maximize revenue across programmatic and direct demand. Liftoff’s solutions, including Accelerate, Direct, Monetize, Intelligence, and Vungle Exchange, support over 6,600 mobile businesses across 74 countries in sectors such as gaming, social, finance, ecommerce, and entertainment. Founded in 2012 and headquartered in Redwood City, CA, Liftoff has a diverse, global presence. About Liftoff Security Team The Liftoff Security team protects Liftoff’s customers, users, and employees. We architect Liftoff’s security posture, build the tools and systems that defend it, and partner with engineering teams as they ship new products and features. Our work spans the entire stack — infrastructure, web, mobile, and IT — and we approach security from a software engineering standpoint, scaling our impact through automation and well-designed tools. 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. Why This Role is Exciting Ownership & Impact : Build and own our in-house offensive security capability, from selecting assessments to confirming fixes. Broad Attack Surface : Test applications, APIs, cloud infrastructure, and corporate systems with access to source code and engineering context. Engineering Partnership : Work with teams that value security and stay involved through remediation and retesting. Room to Grow : Move from point-in-time penetration tests to continuous testing and lead adoption of AI-assisted offensive security tools. Hands-On Technical Work: Investigate complex systems, validate vulnerabilities safely, and build tools that make testing more effective. Compensation : The following are our base salary ranges for this role: SF Bay Area, Los Angeles/Orange County, NYC, Seattle : $200,000 - $250,000 plus bonus All other cities and towns in our approved states: $184,000 - $220,000 plus bonus #LI-EL1 We use Covey as part of our hiring and/or promotional process for jobs in NYC and certain features may qualify it as an AEDT. As part of the evaluation process, we provide Covey with job requirements and candidate-submitted applications. We began using Covey Scout for Inbound on January 22, 2024. Please see the independent bias audit report covering our use of Covey here. Liftoff offers a fast-paced, collaborative, and innovative work environment where employees are empowered to grow and make an impact. We’re shaping the future of the mobile app ecosystem—join us and help accelerate what’s next. Liftoff’s compensation strategy includes competitive salaries, equity, and benefits designed to support employee well-being and performance. We benchmark compensation based on role, level, and location to ensure fairness and market alignment. Benefits may include medical coverage, wellness stipends, and additional perks based on your country of residence. Liftoff is an equal opportunity employer. We are committed to creating an inclusive environment for all employees and applicants regardless of race, ethnicity, national origin, age, marital status, disability, sexual orientation, gender identity, religion, veteran status, or any other characteristic protected by applicable law. Agency and Third Party Recruiter Notice: Liftoff does not accept unsolicited resumes from individual recruiters or third-party recruiting agencies in response to job postings. No fee will be paid to third parties who submit unsolicited candidates directly to our hiring managers or Recruiting Team. All candidates must be submitted via our Applicant Tracking System by approved Liftoff vendors who have been expressly requested to make a submission by our Recruiting Team for a specific job opening. No placement fees will be paid to any firm unless such a request has been made by the Liftoff Recruiting Team and such a candidate was submitted to the Liftoff Recruiting Team via our Applicant Tracking System.