horizon3ai Staff Software Engineer, Backend to lead technical direction and build backend services for the Assessment Experience team at Horizon3. Design scalable APIs and workflows to transform how customers interact with autonomous pentesting.
Responsibilities
We are hiring a Staff Software Engineer, Backend to anchor the technical direction of the Assessment Experience team, transforming how customers work with NodeZero to secure their environment. Assessment Experience is part of the Proactive Offense engineering organization, which builds the core NodeZero product flow: hack, prioritize, fix, verify. Proactive Offense is responsible for driving the outcome the business is built around: allow customers to find weaknesses that represent real risk, remediate them, and prove the fixes actually eliminated attack paths.
Today, NodeZero offers a fairly traditional experience to configure and run pen tests. This team is rethinking that approach to make the experience more outcome based and natural for our customers. NodeZero should feel more like a peer or coworker that customers work with to identify real risk in their environments, and less like a product they need to manage. You will design and build the backend services, APIs, and data models behind that experience.
This is a hands-on role. You will write production code, set the standard for design and operational quality, and raise the technical bar for the engineers around you. You will be expected to be a domain expert and project leader whose influence extends beyond just your team.
What You'll Be Responsible For
Own the technical direction for Assessment Experience backend systems, from initial concept through implementation, iteration, and long-term evolution.
Design and build scalable backend services, APIs, and asynchronous or event-driven workflows that let customers configure assessments and consume their results reliably.
Lead architectural decisions that balance velocity, reliability, data correctness, maintainability, extensibility, and operability, and document the reasoning so others can build on it.
Translate ambiguous product and customer goals into concrete technical strategy, architecture, and execution plans, working closely with Product, Design, and engineering leadership.
Drive problems that cross team boundaries, partnering with teams that own attack content, integrations, and asset matching to define clean interfaces and remove systemic blockers.
Contribute production code and set the standard for design quality, code quality, testing, observability, and safe rollout practices such as feature flags.
Identify risks, dependencies, and tradeoffs early, and help the team sequence work across multiple concurrent initiatives, and evaluate emerging technologies, including AI-driven approaches to outcome-based, conversational experiences, recommending adoption or avoidance with clear rationale.
Raise the technical bar through design reviews, code reviews, architecture proposals, and technical writing that other teams can adopt as standards.
Qualification
You don't need all of theseBuilding or consuming GraphQL backendsGraph databases such as Neo4jUsing feature flags
Preferred
You don't need all of these, but experience in some of the following will help you be successful quickly:
Taking projects with diverse requirements and delivering a consistent unifying experience for customers.
Building or consuming GraphQL backends.
Graph databases such as Neo4j, or interest in learning them.
Familiarity with ETL and streaming data pipelines and data processing frameworks.
Observability stacks (for example Datadog, Prometheus, or Grafana) and service instrumentation.
Leading initiatives around API platforms, workflow-oriented customer experiences, or AI-assisted and conversational product experiences.
Using feature flags, staged rollouts, and customer feedback loops to ship quickly without creating avoidable customer issues.