.Join us in bringing joy to customer experience. Five9 is a leading provider of cloud contact center software, bringing the power of cloud innovation to customers worldwide. Living our values every day results in our team-first culture and enables us to innovate, grow, and thrive while enjoying the journey together. We celebrate diversity and foster an inclusive environment, empowering our employees to be their authentic selves. Our Information Security organisation is seeking an innovative and highly skilled Senior Staff Red Team Security Engineer to join our Offensive Security team. As a key member of this elite group, you will play a crucial role in proactively identifying and mitigating risks to enhance our enterprise security posture. This position demands creative thinking, advanced technical skills, and the ability to simulate sophisticated cyber threats.Key Responsibilities: Design and execute complex, multi-stage Red Team operations that simulate advanced persistent threats (APTs). Develop cutting-edge payloads and attack tools capable of evading modern security controls. Conduct covert operations to assess and improve our organisation's security readiness. Perform targeted attacks using both custom-built and industry-standard tools. Deliver comprehensive technical reports and executive briefings on findings and recommended mitigation strategies. Collaborate with Blue Team members to enhance overall security posture and incident response capabilities. Contribute to the development of new Red Team methodologies and tools. Stay current with emerging cyber threats and attack techniques. Qualifications: Proven experience in Red Team operations and adversary simulation. Advanced skills in developing custom malware and evasion techniques across multiple platforms. In-depth knowledge of adversarial tactics, techniques, and procedures (TTPs). Expertise in both on-premise and cloud-based attack scenarios. Strong programming skills in languages relevant to security testing and tool development. Excellent analytical and problem-solving abilities. Superior written and verbal communication skills, with the ability to convey complex technical concepts to both technical and non-technical audiences. Self-motivation and the ability to work independently as well as in a team environment. Relevant industry certifications (e.G., OSCP, OSCE, GXPN) are a plus. Education: Bachelor's degree in Computer Science, Cybersecurity, or a related field; or equivalent combination of education and experience. Advanced degree or specialised training in cybersecurity is highly desirable. Additional Requirements: Willingness to continuously learn and adapt to the evolving threat landscape. Ability to work in a fast-paced environment and handle multiple projects simultaneously. Strong ethical standards and discretion when handling sensitive information. At Five9, we offer a challenging and rewarding environment for top-tier security professionals