Senior Detection Engineer

Role

We’re looking for a Senior Detection Engineer to join our team. The role will be located in Costa Rica reporting to the Senior Manager of Threat Hunting as part of the Zscaler Threat Hunting team.

Detection Engineers are responsible for advancing threat detection and hunting capabilities of our managed threat hunting service: Zscaler Threat Hunting. This role involves combining Threat Researcher and Detection Engineering skills to develop next-generation detection logic for our threat hunters, utilizing tools like Python, SQL AWS services, YAML-based detection logic, and SIGMA-like rules. The role also contributes to the scalability and maintenance of engineering projects, leveraging data platforms such as Hadoop and Athena. Finally, this position requires independently writing and updating detections and playbooks, which includes working flexible hours, such as weekend night shifts and providing on-call support.

What We're Looking for (Minimum Qualifications)

• Hands-on experience developing and implementing detection rules in a Security Information and Event Management (SIEM) tool, such as Splunk, Microsoft Sentinel, or ElasticSearch


• Familiarity with MITRE ATT&CK framework and experience translating TTPs into actionable detection logic


• Scripting and automation skills using Python for developing and managing detection infrastructure


• Must have excellent reporting and analytical skills and experience writing and optimizing IDS/IPS and YARA signatures


• Must be able to validate detection logic, perform root cause analysis of detection failures, and deliver recommendations for platform improvements

Who You Are (Success Profile)

• You thrive in ambiguity. You're comfortable building the path as you walk it. You thrive in a dynamic environment, seeing ambiguity not as a hindrance, but as the raw material to build something meaningful.


• You act like an owner. Your passion for the mission fuels your bias for action. You operate with integrity because you genuinely care about the outcome. You adapt to what’s needed, navigating seamlessly between high-level strategy and hands-on execution.


• You are a problem-solver. You seek out challenges because you are energized by finding solutions, knowing that solving the hard problems delivers the biggest impact.


• You are a high-trust collaborator. You are ambitious for the team, not just yourself. You embrace our challenge culture by giving and receiving ongoing feedback—knowing that candor delivered with clarity and respect is the truest form of teamwork and the fastest way to earn trust.


• You are a learner. You have a true growth mindset and never stop developing yourself, actively seeking feedback to become a better partner and a stronger teammate. You love what you do and you do it with purpose.

What Will Make You Stand Out (Preferred Qualifications)

• Proven experience in one or more of the following - detection engineering, threat hunting, security operations, malware analysis, blue teaming, or network defence


• Bachelor’s or graduate degree from a four-year college or university (preferably in Computer Science, Engineering, or a related discipline), or equivalent security industry work experience


• Significant and demonstrable experience as a Senior Detection Engineer, leading the development of complex detection strategies and mentoring junior team members


• Experience in network-based threat detection and signature development (e.g., Snort/Suricata rules)