# Senior Backend Engineer, Autonomous Defense at Horizon3.ai

- Company: Horizon3.ai
- What the company does: Horizon3 uses real-world attacks to safely show what attackers can actually do in your environment—so you can fix and prove what matters. Backed by NEA.
- Company website: https://horizon3.ai/
- Type: Startups (AI role)
- Level: Senior
- Location: US, Remote
- Work setup: Remote
- Pay: $170K to $235K base salary per year (USD)
- Posted: 2026-09-14
- Apply by: 2026-10-29
- Apply: https://jobs.ashbyhq.com/horizon3ai/6e817127-7746-4b95-b003-0e58cc233bd1
- Page: https://www.1752.vc/careers/jobs/horizon3-ai-senior-backend-engineer-autonomous-defense/

## About the role

As a Senior Backend Engineer on the Defensive Agent team, you'll build the platform that NodeZero's defensive agents run on. Our AI researchers define what these agents should reason about, you build the systems that make that work in production, across thousands of customer tenants, without breaking anything.

## What they're looking for

- Bachelor's Degree in Computer Science, Computer Engineering or related field
- 7+ yrs professional software engineering experience using modern object-oriented or functional languages (Python, Go, Scala, C++, TypeScript, etc)
- Experience building applications on cloud computing platforms such as AWS, Azure, GCP, using container technologies such as Docker and Kubernetes
- Expert proficiency in SQL
- Demonstrated experience designing and operating distributed systems in production: asynchronous workflows, queues, retries, idempotency, and partial failure
- A track record of shipping and operating production services, including on-call ownership

Tags: Engineering