Staff Technical Support Engineer (Web App)

Get to Know Us Horizon3 is a fast-growing, remote cybersecurity company dedicated to the mission of enabling organizations to proactively find and fix and verify exploitable attack vectors before criminals exploit them. Our flagship product, the NodeZeroTM platform, delivers production-safe autonomous pentests and other key assessment operations that scale across the largest internal, external, cloud, and hybrid cloud environments. NodeZero has been adopted by organizations of all sizes, from small educational institutions to government agencies and Global 100 enterprises. It is used by ITOps/SecOps teams, consulting pentesters, and MSSPs and MSPs.  We are a fusion of former U.S. Special Operations cyber operators, startup engineers, and formerly frustrated cybersecurity practitioners. We're committed to helping solve our common security problems: ineffective security tools, false positives resulting in alert fatigue, blind spots, "checkbox” security culture, cybersecurity skills shortage, and the long lead time and expense of hiring outside consultants. Collectively, we are a team of learn it alls, committed to a culture of respect, collaboration, ownership, and results.   WHAT YOU'LL DO - Investigate complex failures across the entire stack. A single case might take you from Kubernetes pod scheduling, through container networking, into cloud IAM permissions, and into our application logs in Datadog. You own the investigation end to end. - Be the technical bridge between customers and engineering. You'll translate customer-reported symptoms into actionable bug reports with reproduction steps, logs, and root cause hypotheses. When engineering ships a fix, you verify it actually solves the problem in the customer's environment. - Build tooling and automation. If you're doing something manually more than twice, you build a tool. We need someone who writes Python scripts, builds internal dashboards, automates data collection from Zendesk and Jira, and creates runbooks that make the whole team more effective. - Drive systemic improvements. You'll spot patterns across tickets that point to product gaps, documentation holes, or infrastructure reliability issues. You bring the data, make the case, and work with engineering and product to fix the root cause, not just the symptom. - Go deep on web application security. Our platform now does web app pentesting. You need to understand common vulnerability classes (OWASP top 10), how web scanners work, and how to explain findings and their implications to customers who range from security experts to IT generalists. - Mentor the team and raise the technical bar. You'll help junior and senior engineers develop their troubleshooting skills, create training content, and establish patterns for how the team approaches complex investigations. WHAT WE'RE LOOKING FOR Must have: - 8+ years of hands-on technical experience. The title on your resume matters less than what you've actually done. We'll take an SRE who built incident response tooling, a backend developer who ran production infrastructure, or a support engineer who can write real code and read Terraform. - Strong Linux fundamentals. You're comfortable on a command line, can troubleshoot a hung process on RHEL, understand SELinux, and don't need a GUI to be productive. - Container and Kubernetes experience. You've deployed and troubleshot containerized workloads. You know the difference between a CrashLoopBackOff and an ImagePullBackOff and what to do about each. - Cloud platform experience (AWS, Azure, or GCP). You understand IAM, networking (VPCs, security groups, firewalls), and have worked with Infrastructure as Code tools (Terraform, Ansible, or CloudFormation) -- not just reading plans, but writing and debuggi