Senior Technical Support Engineer, EMEA

Get to Know Us

Horizon3.ai is a fast-growing, remote cybersecurity company dedicated to the mission of enabling organizations to proactively find, 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 IT Ops/SecOps teams, consulting pentesters, and MSSPs and MSPs.

We are a fusion of former U.S. Special Operations cyber operators, startup engineers & operators, and formerly frustrated cybersecurity practitioners. We're committed to helping solve our common security problems: ineffective security tools and 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

We are seeking a motivated Mid to Senior Level Enterprise Technical Support Engineer with 5+ years of hands-on industry experience to join our high-performing support team. In this role, you will serve as a key technical resource for our enterprise customers, diagnosing and resolving complex issues related to cloud infrastructure, networking, and security. You'll collaborate with cross-functional teams to ensure seamless customer experiences, leveraging your expertise in Linux, containerization, and cloud technologies. This position requires a proactive self-learner who thrives in fast-paced enterprise environments and can handle escalated support tickets with minimal supervision.

Key Responsibilities

• Provide advanced technical support to enterprise customers via phone, email, chat, and remote sessions, troubleshooting issues across cloud, networking, and infrastructure domains.

• Diagnose and resolve customer-reported problems, performing root cause analysis to prevent recurrence and ensure high availability of services.

• Collaborate with engineering, product, and sales teams to escalate and resolve intricate technical challenges, while documenting solutions for knowledge sharing.

• Assist in the deployment and optimization of customer environments, offering guidance on best practices for infrastructure as code (IaC) and containerized applications.

• Monitor and respond to support tickets in a timely manner, maintaining SLAs and contributing to continuous improvement of support processes.

• Mentor junior team members and contribute to internal training resources, fostering a culture of knowledge transfer and technical excellence.

• Stay abreast of emerging technologies and industry trends to enhance support capabilities and customer satisfaction.

Required Qualifications

• Bachelor's degree in Computer Science, Information Technology, Engineering, or a related field (or equivalent professional experience).

• 5+ years of relevant industry experience in technical support, systems administration, or cloud operations, ideally in an enterprise-level environment (e.g., supporting large-scale deployments for Fortune 500 clients).

• Background in cybersecurity, including knowledge of threat detection, vulnerability management, encryption standards, and compliance frameworks (e.g., SOC 2, GDPR).

• Strong proficiency in Linux administration, including server configuration, performance tuning, security hardening, and troubleshooting in production environments.

• Hands-on experience with Docker and containerization technologies, such as building, deploying, and managing containerized applications in orchestrated environments (e.g., Kubernetes or similar).

• Solid understanding of cloud platforms (e.g., AWS, Azure, or GCP) and Infrastructure as Code (IaC) tools like Terraform, Ansible, or CloudFormation, with experience provisioning and managing cloud resources.

• In-depth knowledge of networking fundamentals, including TCP/IP, firewalls, VPNs, load balancers, and network troubleshooting tools (e.g., Wireshark, tcpdump).

• Basic scripting skills in languages such as Bash, Python, or PowerShell for automation of routine tasks, diagnostics, and simple workflow enhancements.

• Demonstrated self-learning ability, evidenced by personal projects, home labs, certifications (e.g., AWS Certified Solutions Architect, Linux+, or equivalent), or contributions to open-source communities, with a track record of adapting to new technologies independently.

• Experience equivalent to a junior cloud administrator role in an enterprise setting, managing multi-tenant environments, resource allocation, and compliance requirements.

• Familiarity with identity management systems, including Role-Based Access Control (RBAC), Single Sign-On (SSO) protocols (e.g., OAuth, SAML), and directory services (e.g., Active Directory, LDAP).

• Basic understanding of database concepts, including relational and schemaless databases (e.g., SQL vs. NoSQL), schema design, querying, and basic administration tasks.

Preferred Qualifications

• Proven experience integrating and troubleshooting APIs, including RESTful services, authentication mechanisms, and API-driven automations in enterprise applications.

• Familiarity with observability tools like Datadog, including monitoring, logging, and alerting for distributed systems to enhance system reliability and performance.

• Basic experience with managed database services such as Amazon RDS, including setup, backups, scaling, and query optimization.

• Full-stack coding proficiency in languages like Python, JavaScript, or Go, with experience developing custom tools or scripts for support automation.

Travel Required

We are ideally looking for someone to be based hybrid in our Amsterdam office or can be remote in UK, France, Ireland or Spain.

Compensation and Values

At Horizon3, we believe that our people are our greatest asset, and our compensation philosophy reflects this core value. We are committed to fostering an environment where all employees feel valued, respected, and rewarded for their contributions. Our compensation structure is designed to be fair, competitive, and transparent, ensuring that every team member is recognized and compensated equitably across roles, levels, and locations.

• Additional compensation: All full-time roles are eligible for an equity package in the form of stock options.

Perks of Horizon3.ai

• Inclusive Team: We value diversity and promote an inclusive culture where everyone can thrive.

• Growth Opportunities: Be part of a dynamic and growing team with numerous career development opportunities.

• Innovative Culture: Work in a collaborative environment that encourages creativity and out-of-the-box thinking.

• Competitive Compensation: We offer competitive salary, equity and benefits. Our benefits include health, vision & dental insurance for you and your family, a flexible vacation policy, and generous parental leave.

You Belong Here

Horizon3 is not just an equal opportunity employer - we are a community that values diversity, equity, and inclusion as fundamental principles of our culture and success. We are dedicated to fostering a workplace where everyone feels welcome and respected, regardless of race, color, religion, sex, national origin, age, disability, veteran status, sexual orientation, gender identity or expression, genetic information, marital status, hair length or any other legally protected status by law.

Our commitment to diversity and inclusion means we strive to attract, develop, and retain a workforce that reflects the varied communities we serve. We believe that diverse perspectives drive innovation and strengthen our ability to create cutting-edge cybersecurity solutions. At Horizon3, every team member is valued and supported in an environment that encourages personal and professional growth.

We welcome candidates from all backgrounds and experiences, and we encourage all qualified individuals to apply. Come be a part of Horizon3, where your unique contributions are recognized, and your potential is limitless.

Other Duties

Please note this job description is not designed to cover or contain a comprehensive listing of activities, duties or responsibilities that are required of the employee. Duties, responsibilities, and activities may change at any time with or without notice.

Application Note

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