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.

About the Role

We’re looking for an HR Operations Specialist to join our People team and support our growing international workforce, with a primary focus on the Netherlands and broader EMEA region. This role is about execution excellence: you’ll keep our core HR processes running smoothly, ensure clean and compliant data across systems, and help us build scalable ways of working as we grow globally.

Roughly 80% of your time will be focused on HR Operations, with about 20% dedicated to Workplace Support responsibilities in our Amsterdam office. You’ll report into our Senior HR Partner, International, and work closely with colleagues across People Operations, Total Rewards, Workplace, Finance, Legal, and IT.

This is a great opportunity for someone early in their HR career who enjoys highly operational work, loves organizing and documenting processes, and thrives in a fast-paced, dynamic start-up environment.

What You’ll Do

• HR Operations

  • Run core HR processes for our international employees, including onboarding, job changes, offboarding, and contract changes, ensuring a smooth, consistent experience for our Netherlands and broader EMEA population.

  • Maintain clean, accurate employee data and documentation across our HR systems (e.g., Rippling, Deel), including preparing and updating employment documents (offers, addenda, letters, templates) and supporting compliance with Dutch and EU employment requirements.

  • Coordinate with payroll, benefits, and immigration partners (entity and EOR) to support timely, accurate processing, including sharing data changes, checking outputs, supporting visa and work authorization processes (eg., highly skilled migrant applications), and helping resolve discrepancies.

  • Own documentation hygiene and first-line HR support for global HR operations: organize folders, refresh outdated content, maintain clear SOPs, checklists, and FAQs, and act as a first-line contact for employees and managers on operational HR questions, escalating complex or sensitive matters appropriately.

  • Contribute to international HR projects and continuous improvement, including documentation clean-up, process mapping, local policy/handbook updates, onboarding improvements, identifying and suggesting “1% improvements” to workflows, and collaborating cross-functionally with People, Workplace, Finance, Legal, and IT.

• Workplace Support

  • Serve as the primary on-the-ground contact for our Amsterdam office, partnering with our serviced office provider, local leadership, and the Workplace team to keep the space running smoothly.

  • Coordinate day-to-day office needs, including supplies, snacks, mail/packages, access badges, and basic facilities requests, escalating building or vendor issues as needed.

  • Support local internal events and culture-building activities (e.g., team lunches, onsite meetings, celebrations), handling logistics such as catering, room setup, and vendor coordination.

  • Monitor the overall employee experience in the office, surfacing feedback and ideas to improve how the space supports collaboration, focus, and connection, and helping maintain an organized, welcoming environment.

What You’ll Bring

• 2+ years of experience in HR Operations / HR Administration, with a solid understanding of core HR processes (onboarding, job changes, offboarding, data changes, documentation), ideally supporting employees in the Netherlands and/or broader EMEA.

• Familiarity with Dutch employment practices (e.g., basic knowledge of holidays, sick leave, probation, notice periods); experience with other European markets is a plus.

• Strong systems and data orientation, comfortable working in HRIS/HR tools (e.g., Rippling, Deel, Ashby or similar), managing spreadsheets, and keeping records accurate and organized.

• High attention to detail and strong organization, with a track record of managing multiple small workflows at once, prioritizing effectively, and following through on repetitive operational tasks in a fast-moving environment.

• Comfort in an office-facing role, including facilities coordination, vendors, office supplies, and basic event logistics, and serving as the on-site point of contact in Amsterdam several days per week.

• Growth mindset and team-first approach, with strong communication skills in English (written and verbal), Dutch language skills strongly preferred, and the adaptability and resilience needed to collaborate across time zones in a fast-paced, scaling global environment.

Why Join Us?

• Make Your Mark: You’ll have the opportunity to influence and shape HR practices in one of our most important international hubs.

• Global Impact, Local Expertise: Be the voice of Dutch and European HR while contributing to an integrated, worldwide People strategy.

• Trusted Advisor Role: Gain visibility across the business as a go-to partner for leaders.

• Collaborative Culture: Join a supportive, innovative, and globally connected People team that prioritizes employee experience.

• Competitive Rewards: Enjoy a compensation and benefits package tailored to the Dutch market.
  

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.

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.

• Hybrid & Remote Work: We embrace a mix of remote and hybrid work models depending on role and location, including our Chicago office, where some roles require regular in-office presence.

• 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

In any materials you submit, you may redact or remove age-identifying information such as age, date of birth, or dates of school attendance or graduation. You will not be penalized for redacting or removing this information.