Back End Engineer

Horizon3 AI

1d • $130,000 - $190,000 • Remote

About The Position

We’re looking for a Backend Engineer to join our Application Platform Team (APT). APT owns cross-cutting platform features for the Horizon3.ai engineering team, and has a mandate to build out a world-class application platform which is reliable, scalable, and performant. As a Backend Engineer, you’ll help build and improve the backend systems and APIs that power NodeZero’s production-scale pentesting and reporting. You’ll work alongside experienced engineers to implement features, improve stability and performance, and make it easier for other Horizon3 teams to build on the platform.
This description reflects a mid level role: you’ll have meaningful ownership of components and projects, with strong mentorship and support from senior engineers and managers.

Requirements

• Ownership mindset at the feature/component level: You can take a scoped project from design discussion through implementation, testing, and rollout with guidance.
• You’re comfortable asking for help early when requirements or tradeoffs are unclear.
• Strong collaboration skills: Clear, concise written and verbal communication.
• Ability to work effectively with designers, frontend engineers, product, and customer-facing teams.
• Growth and learning orientation: Curiosity about how distributed systems, ETL pipelines, and APIs come together to support a complex SaaS product.
• Willingness to learn from senior engineers and to work in areas that might be new to you (e.g., graph databases, large-scale ETL, or advanced observability).
• Attention to quality: You care about testing, clear documentation, and building systems that are debuggable and observable in production.
• You’re comfortable iterating quickly while still keeping reliability in mind.
• Bachelor’s degree in Computer Science, Computer Engineering, or a related field, or equivalent practical experience.
• 1–4 years of professional software engineering experience.
• Experience building backend services using at least one modern language, such as Python, Go, Java, TypeScript, or similar.
• Experience working with SQL and at least one relational database in production.
• Experience building backend services on a cloud platform (AWS, GCP, or Azure), and familiarity with Docker and containerized applications.

Nice To Haves

• You don’t need all of these, but experience in some of the following will help you ramp faster on the Application Platform Team:
• Experience with PostgreSQL and performance tuning for large datasets.
• Experience with graph databases such as Neo4j or interest in learning them.
• Experience building or consuming GraphQL backends.
• Experience with ETL pipelines and data processing tools (e.g., Airflow-like frameworks, custom ETL jobs, or similar).
• Experience working on platform or infrastructure-facing teams, building capabilities that other engineering teams use.
• Experience with observability stacks (e.g., Datadog, Prometheus, Grafana) and instrumentation of services.

Responsibilities

• Build and enhance backend services that power NodeZero, with a focus on: ETL jobs and data pipelines used to process and analyze large graph and relational datasets.
• GraphQL APIs used by customer-facing features and internal tools (such as authentication, our internal management portal, reporting flows, and more).
• Improving the entrypoint to NodeZero, ensuring NodeZero runs seamlessly on various operating systems and provides improved observability into customer faced issues on installation process.
• Implement and evolve backend APIs in GraphQL and Python to support: Internal tools that enable managing customer accounts and operations at scale
• Product features that rely on reliable, performant data access.
• Help build foundational integrations platform
• Be involved in a new initiative to help scale Horizon3’s ability to integrate a large number of new partners.
• Help improve developer experience and API quality and operational readiness to ensure partner integrations are seamless.
• Collaborate closely with other teams: Partner with product, frontend, and other engineering squads to ship user-facing improvements.
• Work with on-call and support engineers to debug production issues and improve reliability.
• Contribute to platform performance and stability, including: Improving ETL and post-ETL performance around attack vectors and large customer environments.
• Enhancing observability and monitoring for runner queues, ETL jobs, and core APIs.
• Attack vector and asset graph processing.
• Platform features like runner queues, customer entitlements, and client migrations.
• Participate in code reviews, testing, and documentation, helping raise the quality bar across the team.

Benefits

• 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.

What This Job Offers

• Job Type: Full-time
• Career Level: Mid Level