Senior Backend Engineer, Autonomous Defense
Horizon3 AI3 days ago
Remote, United StatesSenior
Base Salary
$170k - $235k/yr
Responsibilities
- Build and own a durable, resumable agent execution runtime with checkpointing, idempotency, cancellation, and timeouts.
- Design a versioned agent tool layer with schema validation, per-tenant enablement, and server-side authorization.
- Build connector integrations for EDR, firewall, identity, SIEM, and cloud IAM control planes.
- Implement simulation, approval, staged rollout, rollback, blast-radius classification, and immutable audit workflows for production changes.
- Extend tenant isolation for agent write actions, including execution boundaries, egress controls, quotas, and prevention of cross-tenant leakage.
- Develop ETL and GraphQL product features and pipelines supporting agent context, run history, remediation state, and research datasets.
- Instrument agent runs with distributed tracing, per-tenant cost and token accounting, and debugging tools.
- Partner with AI researchers, attack engineers, and product teams to move capabilities from prototype to production.
Requirements
- Bachelor’s degree in Computer Science, Computer Engineering, or a related field.
- 7+ years of professional software engineering experience using modern object-oriented or functional languages.
- Experience building applications on cloud platforms such as AWS, Azure, or GCP and using Docker and Kubernetes.
- Expert proficiency in SQL.
- Demonstrated experience designing and operating production distributed systems involving asynchronous workflows, queues, retries, idempotency, and partial failure.
- Track record of shipping and operating production services, including on-call ownership.
- Preferred experience with agentic or LLM-backed production systems, durable execution or workflow engines such as Temporal, multi-tenant platforms, workload identity, and short-lived credential brokering.
- Preferred experience integrating third-party APIs, security control-plane APIs, relational and graph databases, GraphQL backends, observability tooling, and distributed tracing.
- Awareness of prompt injection and untrusted-input handling in agent systems.
Benefits
- Remote and hybrid work models are available depending on role and location, including the Chicago office where some roles may require regular in-office presence.
- Health, vision, and dental insurance are available for employees and their families.
- Flexible vacation policy and generous parental leave.
- Full-time roles are eligible for an equity package in the form of stock options.
- Inclusive culture and career development opportunities.
Tech Stack
AWSAzureC++DatadogDockerGoGoogle Cloud PlatformGrafanaGraphQLKubernetesNeo4jPostgreSQLPrometheusPythonScalaSQLTypeScript
Categories
About Horizon3 AI
Horizon3 AI builds NodeZero, a proactive security platform that autonomously performs penetration testing and validates attack paths across on‑prem, cloud, and hybrid environments. The company sells its software by subscription to security and IT teams at enterprises and government agencies, helping prioritize and verify fixes. Founded in 2019 and headquartered in San Francisco, it is privately held and serves customers across regulated industries and the public sector.