Who we are:
Horizon3’s mission is to enable organizations to proactively find and fix and verify exploitable attack vectors before criminals exploit them. We are a fast-growing, remote cybersecurity company using automation and artificial intelligence to deliver Autonomous Penetration Testing as a Service (APTaaS). We are a team of learn it alls, committed to a culture of respect, collaboration, ownership, and results.
Overview
We are seeking a highly skilled Senior Software Engineer specializing in Developer Tools & Automation with deep expertise in testing, infrastructure, and system analysis. In this role, you will own the strategy and implementation of automation frameworks, infrastructure deployment pipelines, and observability tooling that drive the reliability, scalability, and quality of our services. You will design and maintain automated controls, test exercisers, log analysis systems, and results tracking frameworks—partnering closely with Engineering, DevOps, and Support to raise the bar for quality and velocity in a fast-paced, agile environment.
Key responsibilities:
Build and maintain Infrastructure-as-Code (IaC) solutions (Terraform, CloudFormation, VMware) to provision complex target environments for testing and development.
Design and lead development of log analysis platforms capable of ingesting and normalizing multi-format data streams (AWS, S3, Azure, OS, networking, Docker, Kubernetes, etc.) with user-facing visualization and reporting.
Own and evolve GraphQL APIs and databases (e.g., Neo4j) used for operational control, automation, and system health tracking.
Architect and implement test exerciser frameworks to validate functionality, performance, and resiliency across distributed services.
Develop results-tracking and observability frameworks with UI and reporting layers to provide real-time visibility into system health and test outcomes.
Drive collaboration across engineering, QA, and product management to define testing strategies, requirements, and automation standards.
Integrate testing frameworks and tooling into CI/CD pipelines (GitLab CI) to enable rapid, reliable delivery.
Contribute to architecture and design discussions, ensuring reliability and testability are first-class considerations.
Provide technical mentorship and leadership in automation, observability, and testing practices.
Required Education/Experience:
Bachelor’s degree in Computer Science, Engineering, or related field (or equivalent professional experience).
6+ years of experience in software development, test automation, DevTools engineering, or SDET leadership roles.
Expert-level proficiency in Python and/or JavaScript/TypeScript, with proven experience building frameworks and automation tooling.
Strong expertise in distributed systems debugging, log analysis, and observability using tools like CloudWatch, Datadog, or equivalent.
Proven experience with GraphQL APIs, Neo4j, Kubernetes, and microservices architectures.
Deep familiarity with AWS services (EC2, S3, Lambda, RDS, DynamoDB, IAM, CloudWatch) and IaC practices.
Hands-on experience with CI/CD automation (e.g., GitLab CI) and automated UI/API testing frameworks (e.g., Playwright).
Strong understanding of QA methodologies, test strategy, and risk-based testing in distributed environments.
Exceptional communication skills with the ability to influence cross-functional stakeholders and advocate for quality at scale.
Preferred Education/Experience:
Demonstrated ability to take projects from concept through design, implementation, and adoption.
Experience with multi-cloud deployments (AWS, Azure) and event-driven architectures.
Strong background in containerized environments (Docker, Kubernetes).
Familiarity with agile delivery practices and leading cross-team initiatives.
AWS Certifications (Developer or Solutions Architect) are highly valued.
Citizenship/Clearance
US Citizen Required
Why H3
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.
Growth Opportunities: Be part of a dynamic and growing team with numerous career advancement opportunities.
Innovation-Driven Culture: Work in a collaborative environment that encourages creativity and out-of-the-box thinking.
Flexible Work Environment: Enjoy the convenience and work-life balance that comes with remote work.
Inclusive and Diverse Team: We value diversity and promote an inclusive culture where everyone can thrive.
Travel Required
We are a fully remote company, and this job may require up to 5% of travel to be successful. Job-related travel expenses are reviewed and must be approved by your manager.
Compensation Disclosure:
In accordance with various State’s transparency regulations, we provide the following salary range information for this position:
Base salary range (based on level):
P4, Tier 1–2: $165,000 - $205,000
P5, Tier 1–2: $190,000 – $235,000
This position may be filled at either the P4 or P5 level depending on experience, skills, and interview performance. Final compensation is further determined by Tier 1 vs. Tier 2 location alignment.
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.
Join Horizon3.AI’s team of passionate professionals and contribute to the growth of cutting-edge cybersecurity solutions while building strong customer relationships in a dynamic and remote work environment.
Horizon3.ai is an equal opportunity employer and is committed to providing a work environment that is free from discrimination and harassment. We do not discriminate based on race, color, religion, sex, national origin, age, disability, veteran status, sexual orientation, gender identity or expression, genetic information, marital status, or any other legally protected status.
We believe that diversity and inclusion are essential to our success as a company and as a community. We are committed to attracting, developing, and retaining a diverse workforce that represents the communities in which we operate. We strive to create an inclusive work environment where all employees feel valued, respected, and supported.
We encourage all qualified candidates to apply for open positions with our company and welcome candidates from all backgrounds and experiences.
Top Skills
What We Do
Horizon3.ai's mission is to help you find and fix attack vectors before attackers can exploit them. NodeZero, our autonomous penetration testing solution, enables organizations to continuously assess the security posture of their enterprise, including external, identity, on-prem, IoT, and cloud attack surfaces.
Like APTs, ransomware, and other threat actors, our algorithms discover and fingerprint your attack surface, identifying the ways exploitable vulnerabilities, misconfigurations, harvested credentials, and dangerous product defaults can be chained together to facilitate a compromise.
NodeZero is a true self-service SaaS offering that is safe to run in production and requires no persistent or credentialed agents. You will see your enterprise through the eyes of the attacker, identify your ineffective security controls, and ensure your limited resources are spent fixing problems that can actually be exploited.
Founded in 2019 by industry, US Special Operations, and US National Security veterans, Horizon3.ai is headquartered in San Francisco, CA, and made in the USA.
