---
title: 'Principal Backend Engineer, Enterpise Platform at Horizon3 AI'
canonical: 'https://feeny.ai/job/principal-backend-engineer-enterpise-platform-horizon3-ai-united-states-p0jmsqyt2xqb'
type: 'job'
last_seen: '2026-11-07'
---

# Principal Backend Engineer, Enterpise Platform at Horizon3 AI

- **Company:** [Horizon3 AI](https://feeny.ai/companies/horizon3-ai)
- **Location:** United States
- **Employment:** full-time
- **Work type:** remote
- **Posted:** 2026-11-03
- **Last confirmed live:** 2026-11-07
- **Apply:** https://jobs.ashbyhq.com/horizon3ai/729616b9-52bc-49ea-8216-6d2002549964

## Job description

Get to Know Us Horizon3 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

As a Principal Software Engineer on the Enterprise Platform team, you’ll set technical direction for foundational services that power NodeZero’s customer and partner experiences. You’ll help shape how the platform manages licensing and entitlements, account administration, onboarding and provisioning, notifications, and asset workflows for managed service and security providers. You’ll guide architecture and execution across teams, partnering with Engineering, Product, and business leaders to make complex platform capabilities secure, reliable, and operable at scale. This is a hands-on individual-contributor role with company-wide technical influence; you’ll develop other technical leaders through mentorship and technical guidance, not formal people management.

## Responsibilities

- Set long-term technical direction for Enterprise Platform capabilities, including licensing and entitlements, user access and account administration, onboarding and provisioning, product and usage notifications, and MSP/MSSP client and sub-client workflows.
- Guide architecture for multi-tenant services and account models, including parent-child relationships, permissions, product access, usage limits, and asset allocation across customer and partner accounts.
- Partner with Engineering, Product, and business leaders to shape technical priorities and investment decisions; make clear tradeoffs across customer value, security, reliability, scale, delivery speed, and maintainability.
- Lead high-impact, cross-team technical initiatives from ambiguous problem to durable solution, establishing the design principles and outcomes teams can execute against.
- Stay close to implementation through design reviews, code reviews, technical investigation, and hands-on contributions to critical systems where useful.
- Improve production reliability and supportability through testing, observability, monitoring and alerting, safe rollout practices, incident learning, and clear runbooks and support documentation.
- Help balance product delivery with operational support, on-call health, and long-term platform investment.
- Mentor senior engineers and technical leaders, and create reusable technical guidance that raises engineering quality across teams.
- Communicate architecture, risks, and decisions clearly to technical and non-technical stakeholders.

## What You’ll Bring

- A record of sustained technical impact across multiple teams, including contributions that shaped company-level technical direction.
- Deep experience with backend services or multi-tenant SaaS platforms, including production ownership of business-critical systems.
- Strong architectural judgment across complex data models, distributed systems, security, reliability, and scalability tradeoffs.
- A history of earning trust with senior technical, product, and business partners through clear communication and sound decisions.
- A track record of raising engineering quality and developing senior technical talent through influence and mentorship.

Required Education / Experience

- Bachelor’s degree in Computer Science, Computer Engineering, or a related field, or equivalent practical experience.
- Extensive professional software engineering experience building and operating production backend services.
- Demonstrated technical leadership and impact beyond a single team.
- Experience designing APIs and data models for multi-tenant or customer-facing SaaS systems.

Required Tech Stack Experience

- Deep experience building and operating backend services in a modern language such as Python, Go, Java, or TypeScript.
- Strong SQL and relational data modeling experience, along with API and service design for production systems.
- Experience building cloud-hosted services and operating containerized applications such as Docker; familiarity with Kubernetes or a comparable orchestrator.
- Experience with every example technology is not required; depth in relevant areas and the ability to make sound technical choices are important.

What Sets You Apart?

- Experience with MSP/MSSP, reseller, or other partner software models.
- Experience with account hierarchies, delegated administration, tenant isolation, or role-based access control (RBAC).
- Experience with licensing, entitlements, asset allocation, usage limits, or product notifications.
- Experience with Python or Go, AWS, PostgreSQL, GraphQL, Docker, and Kubernetes.
- A history of leading platform or architecture changes that improved reliability, delivery speed, developer effectiveness, or customer outcomes across an organization.

Travel Required We are a fully remote company, and this job may require up to 5% of travel to be successful.

## 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. In accordance with various State’s transparency regulations, we provide the following salary range information for this position:

- Base salary range $255,000 - $295,000 annually. The exact salary will be determined based on the selected candidate’s location, qualifications, experience, and relevant skills.
- Additional compensation: All full-time roles are eligible for an equity package in the form of stock options.

## Perks of Horizon3

- 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.

## About Horizon3 AI

## Company Overview
- **One-liner**: Horizon3.ai provides an autonomous penetration testing platform (NodeZero) that safely hacks production environments to identify and fix exploitable attack paths using AI.
- **Entity Type**: Private (Series D – latest funding round in 2026, led by Prosperity7 Ventures)
- **Headquarters**: San Francisco, California, United States (447 Battery Street, San Francisco, CA 94111)
- **Founded**: 2019
- **Founders**: Snehal Antani (Co-Founder & CEO); founded by a mix of US Special Operations, US National Security, and cybersecurity industry veterans

## Core Business
- **Primary industry**: Cybersecurity (autonomous penetration testing, vulnerability management, continuous security validation)
- **Target customers**: B2B – large enterprises, Fortune 100, government agencies (NSA, CISA), healthcare providers, financial services, manufacturing, education, public sector
- **Mission**: “Turn the map around” – using the attacker’s perspective to help enterprises prioritize defensive efforts. The company aims to shift the advantage from attackers to defenders by fighting AI with AI.

## Products & Services
- **[NodeZero®](https://horizon3.ai/)**: Autonomous penetration testing SaaS platform. Safely runs real attack techniques in production environments (no agents, no disruption). Discovers and chains exploitable vulnerabilities, misconfigurations, harvested credentials, and dangerous defaults across external, identity, on-prem, cloud, and Kubernetes attack surfaces. Also includes Active Directory password auditing and phishing impact testing. Continuously validates fixes and repeats autonomously.

## Market Standing
- **Valuation**: Not publicly disclosed
- **Key Metrics**: 
  - Annual Revenue: **$35.5M** (per LinkedIn)
  - Total Funding: **$187M** (per LinkedIn) / **$181M** (per CB Insights – conflicting reports; both cited)
  - **225,000+** production-safe tests completed
  - **5,000+** customers
- **Notable Investors/Partners**: 
  - SignalFire (lead in Seed, Series A, Series B)
  - Craft Ventures (lead Series C)
  - Prosperity7 Ventures (lead Series D – 2026)
- **Growth Signals**:
  - Ranked **#1 in Security** on the 2025 Inc. 5000 list
  - **#3 overall** on the 2025 Deloitte Technology Fast 500
  - Fast Company’s **Most Innovative Companies** (2026) – #1 in Security
  - Named to the **Fortune Cyber 60** (2023 & 2025)
  - Two-time **Black Unicorn Award** winner
  - Headcount grew **115.5% YoY** to 341 employees (LinkedIn)
  - Active job postings up **168.2% YoY**; operates in 14 countries

## Competitive Advantages
- **AI-driven autonomous testing** that learns from hundreds of thousands of tests and uses the right AI (ML, GenAI) for each problem – delivers evidence-based results with **zero hallucinations**.
- **Production-safe** – zero downtime across all production tests, trusted by the world’s most sensitive high-security environments (NSA, CISA, Fortune 10, major healthcare).
- **No agents required** – fully self-service SaaS, safe to run continuously.
- **Real attack techniques** – not a scanner; shows actual attacker paths and impact.
- **Rapid verification** – instantly confirms fixes and repeats the cycle, enabling a continuous validation loop.

## Strategic Focus
- **Continuous validation** – driving a loop of test-fix-verify-repeat autonomously.
- **Fighting AI with AI** – building NodeZero to operate at machine speed against AI-powered attacks.
- **Global expansion** – already in 14 countries, with active hiring in EMEA, APAC, and the Americas.
- **Scaling the team** – 59 active job postings (as of mid-2026), with emphasis on engineering, sales, and customer success roles.

## Why Work Here
- **Culture**: Rated **5.0/5.0 on LinkedIn** (76 reviews) with perfect scores for Culture (5.0), Career (4.9), Compensation (4.7), and Work-Life (4.6). Described as a “kick-ass organization hell bent on disrupting an industry” with a team of “motivated learn-it-alls.”
- **Work Policy**: Remote-friendly (most roles listed as remote, HQ in San Francisco, CA). Offers flexibility across time zones.
- **Notable Perks** (from Built In and LinkedIn):
  - Comprehensive healthcare (medical, dental, vision, FSA)
  - Life insurance, disability insurance
  - 401(k) with company matching
  - Equity and employee stock purchase plan
  - Generous parental leave and family medical leave
  - Performance bonuses
  - Job training, conferences, and customized development tracks
  - Promotion policies and career growth support
- **Engineering Culture**: Built by US Special Operations and National Security veterans. Emphasis on high autonomy, real-world impact, and cutting-edge AI/security work. “If you want to be part of a kick-ass organization hell bent on disrupting an industry and keeping attackers at bay, let’s talk.”

## Sources
1. [horizon3.ai – Homepage](https://horizon3.ai/)
2. [horizon3.ai – About/Team](https://horizon3.ai/about-us/)
3. [LinkedIn – Horizon3.ai Company Page](https://www.linkedin.com/company/horizon3ai)
4. [Built In – Horizon3.ai Careers & Perks](https://builtin.com/company/horizon3ai)
5. [CB Insights – Horizon3.ai Profile](https://www.cbinsights.com/company/horizon-3-ai)

## Other roles at Horizon3 AI

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