Staff Software Engineer, Database Platform

Get to Know Us Horizon3 http://Horizon3.ai is a fast-growing, remote cybersecurity company dedicated to the mission of enabling organizations to proactively find, fix and verify exploitable attack vectors before criminals exploit them. Our flagship product, the NodeZero™ platform, delivers production-safe autonomous pentests and other key assessment operations that scale across the largest internal, external, cloud, and hybrid cloud environments. NodeZero has been adopted by organizations of all sizes, from small educational institutions to government agencies and Global 100 enterprises. It is used by IT Ops/SecOps teams, consulting pentesters, and MSSPs and MSPs. We are a fusion of former U.S. Special Operations cyber operators, startup engineers & operators, and formerly frustrated cybersecurity practitioners. We're committed to helping solve our common security problems: ineffective security tools and false positives, resulting in alert fatigue, blind spots, "checkbox" security culture, cybersecurity skills shortage, and the long lead time and expense of hiring outside consultants. Collectively, we are a team of learn-it-alls, committed to a culture of respect, collaboration, ownership, and results. As a remote first company, we require minimum 25Mbps consumer grade broadband connection.     What You'll Do The Staff Engineer on the DB Platform team is the technical anchor for database architecture and reliability across Horizon3. NodeZero runs thousands of pentests generating enormous volumes of structured data — vulnerability findings, asset graphs, scan histories, time-series telemetry, and customer configurations. Every team at Horizon3 depends on the data stores this team builds and operates. You will set the technical direction for how Horizon3 designs, provisions, scales, and operates its database systems — from PostgreSQL and graph databases to time-series stores. This is a hands-on staff-level role. You will write production code, produce architecture designs, drive critical performance and reliability decisions, and mentor engineers through the craft of database engineering. The team is building from a small but strong foundation — your job is to raise the technical bar dramatically as the data volumes and query complexity grow. This role reports to the Data Platform Engineering Manager. Responsibilities - Database Architecture: Set the technical direction for Horizon3's database systems — schema design philosophy, data modeling standards, indexing strategies, and query contract design across teams - Performance Engineering: Own query performance across the platform — identify slow queries, produce execution plan analyses, implement fixes, and design the observability systems that catch regressions early - Reliability & Operations: Own the reliability engineering for all data stores — replication, failover, backup validation, capacity planning, and database incident response - Migration Engineering: Design and own the migration framework that makes schema evolution safe in production — zero-downtime migrations, reversible changes, and migration testing standards - Cross-team Enablement: Serve as the database expert for application engineering teams — review their schemas, query patterns, and ORM usage; set the access patterns that prevent problems from reaching production - Mentorship: Mentor P4 engineers through design review, code review, and deep technical pairing; be the person the team turns to when they hit a hard database problem     What You'll Bring Database Engineering - 8+ years of professional software engineering experience with deep specialization in database systems and data infrastructure - Expert-level PostgreSQL proficiency — you have tuned complex production query plans,