Note: The job is a remote job and is open to candidates in USA. Horizon3.ai is a remote cybersecurity company that develops the NodeZero platform for autonomous penetration testing and security assessment operations. The Senior Back-End Software Engineer will design, build, and operate real-time, event-driven services that transform pentest telemetry into findings, attack paths, reports, and insights at enterprise scale.
Responsibilities
- Design, build, and operate event-driven services that process pentest data in real time event streaming, stream processing, storage, schema evolution, and replayable processing
- Take ambiguous, high-impact problems from "we need to solve this" through design, implementation, rollout, and long-term operation, without needing the path drawn for you
- Help solve challenges around converting large per-pentest datasets, and converting that to a cohesive story over time. Tackling challenging problems such as understanding when two hosts are the same even with different IP addresses
- Translate existing batch-era logic — finding enrichment, attack path analysis, host and identity correlation, reporting — into streaming-friendly designs without regressing fidelity
- Solve genuinely hard distributed systems problems at scale: breaking out a half-decade hold monolithic data-storage for an engineering org that is rapidly growing in both scale of customers and number of engineering teams
- Set a high bar for operational excellence — SLOs, instrumentation, alerting, on-call, and incident response, as this system becomes central to every pentest Horizon3 runs
- Raise the technical bar around you through design reviews, technical writing, clear API contracts with neighboring teams, and durable decision records. Interface with other platform teams and attack-engineering teams
Skills
- As a remote first company, we require minimum 25Mbps consumer grade broadband connection
- Minimum of 4+ years of experience in software engineering or a similar role
- Proficiency in Python and/or Go, including experience with large-scale codebases
- Production experience with relational databases (PostgreSQL) — schema design, migrations, and query performance at scale
- Experience building and operating services in AWS or a comparable cloud, with containers and orchestration (Docker, Kubernetes)
- Hands-on experience with observability tooling (Datadog, OpenTelemetry, or similar) in production
- Bachelor's degree in Computer Science, Computer Engineering, or related field, or equivalent practical experience
- Production experience with event-driven architectures or streaming platforms (Kafka, Kinesis, Flink, or similar)
- Experience with designing distributed systems at scale, AWS a bonus
- Experience migrating a meaningful system from batch to streaming, or decomposing a monolith into services, while it stayed live for customers
- Graph database experience (Neo4j) and graph data modeling and SQL
- Background in cybersecurity, pentesting, or vulnerability management
- Experience with data-at-rest and in-transit encryption patterns (envelope encryption, KMS)
Benefits
- All full-time roles are eligible for an equity package in the form of stock options.
- Numerous career development opportunities
- A collaborative environment that encourages creativity and out-of-the-box thinking.
- We are a 100% remote company. Enjoy the flexibility to work in the way that supports you and brings out your best.
- Health, vision & dental insurance for you and your family
- A flexible vacation policy
- Generous parental leave
Company Overview