[Hiring] Senior Full-Stack Engineer @Horizon3

Role Description

As a Senior Full-Stack Engineer on the Autonomous Defensive team, you'll build the platform that NodeZero's defensive agents run on. Your responsibilities include:

• Building the agent execution runtime: durable, resumable, long-running workflows with checkpointing, idempotent steps, cancellation, and timeouts.
• Designing and implementing the tool layer that agents act through, including a registry with versioning, schema validation, and server-side authorization.
• Building the connector framework for third-party security control planes (EDR, firewall, identity, SIEM, cloud IAM).
• Implementing the safe-change pipeline: dry-run and simulation, blast-radius classification, approval gates, staged rollout, rollback, and an immutable audit trail.
• Building the operator-facing front end in React and TypeScript.
• Building the client-side data and streaming layer over WebSockets.
• Extending NodeZero's tenant isolation model to agents that take write actions.
• Developing core product features in ETL and GraphQL.
• Building ETL pipelines for pentest and remediation outcomes.
• Instrumenting everything for distributed tracing and cost accounting.
• Partnering with AI researchers and product teams to transition capabilities from prototype to production.

Qualifications

• Bachelor's Degree in Computer Science, Computer Engineering or related field.
• 7+ years of professional software engineering experience using modern object-oriented or functional languages (Python, Go, Scala, C++, TypeScript, etc.).
• Proven experience delivering backend APIs, especially GraphQL.
• Production experience with React, TypeScript, and modern CSS layout.
• Experience building applications on cloud computing platforms such as AWS, Azure, GCP.
• Expert proficiency in SQL.
• Demonstrated experience designing and operating distributed systems in production.
• A track record of shipping and operating production services.

Requirements

• Experience building agentic or LLM-backed systems in production.
• Experience with durable execution or workflow engines.
• Experience building multi-tenant platforms with hard isolation requirements.
• Experience integrating a long tail of third-party APIs.
• Familiarity with security control planes and their APIs.
• Experience with database architectures including relational and graph databases.
• Experience with client-side data and streaming patterns.
• Experience building operator-facing or admin interfaces.
• Experience with observability tooling and distributed tracing.
• Awareness of prompt injection and untrusted-input handling.

Benefits

• Inclusive Team: We value diversity and promote an inclusive culture.
• Growth Opportunities: Numerous career development opportunities.
• Innovative Culture: Collaborative environment that encourages creativity.
• Hybrid & Remote Work: Flexible work models depending on role and location.
• Competitive Compensation: Salary, equity, and benefits including health, vision & dental insurance, flexible vacation policy, and generous parental leave.