Senior Back-End Engineer (Data & App Platform)

• The Pentest Data Platform team owns how NodeZero turns raw pentest telemetry into the findings, attack paths, reports, and insights our customers act on. As Horizon3 has grown in both customer count and customer size. Our team is taking on the largest architectural change in Horizon3’s history: a ground-up rework of pentest data processing from a batch system into a real-time, event-driven microservice architecture
• We’re laying the foundation to make Horizon3 best-in-class for enterprise pentests at scale — handling hundreds of thousands of hosts and streaming findings as they’re discovered. Customers go from waiting weeks for insights to getting them in hours, fundamentally transforming how the entire product suite feels to use
• This work demands platform engineering to build the infrastructure foundation, paired with deep cybersecurity domain understanding to translate years of batch-centric business logic into real-time processing. As a Senior Engineer on this team, you will be one of the people we trust to own a hard piece of that rework end to end
• 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

Benefits

• Growth Opportunities: Be part of a dynamic and growing team with numerous career advancement opportunities
• Innovation-Driven Culture: Work in a collaborative environment that encourages creativity and out-of-the-box thinking
• Flexible Work Environment: Enjoy the convenience and work-life balance that comes with remote work
• Inclusive and Diverse Team: We value diversity and promote an inclusive culture where everyone can thrive

• As a remote first company, we require minimum 25Mbps consumer grade broadband connection
• Experience building and operating large scale distributed services in AWS (or comparable cloud), with containers and orchestration (Docker, Kubernetes)
• Proficiency in Python, Go, or similar languages with experience in large-scale production codebases
• Production experience with PostgreSQL including schema design, migrations, and query performance at scale
• Hands-on experience with production observability tooling (Datadog, OpenTelemetry, or similar)
• Bachelor’s degree in Computer Science, Computer Engineering, or a related field, or equivalent practical experience
• 4+ years of software engineering experience
• Experience migrating a live system from batch to streaming, or decomposing a monolith into services, without customer-facing regression
• Production experience with event-driven architectures or streaming platforms — Kafka strongly preferred; Kinesis or Flink also relevant
• Experience with Redshift or other columnar/analytical data platforms
• Graph database experience (Neo4j) and graph data modeling alongside SQL
• ETL orchestration experience with Argo, Airflow, Temporal, or comparable tools
• Experience with data reconciliation, backpressure, replay, retries, and schema evolution at scale
• Background in cybersecurity, pentesting, or vulnerability management
• Experience with data-at-rest and in-transit encryption patterns (envelope encryption, KMS)