Why Castelion, Why Now 

Castelion is moving incredibly fast to develop and deliver advanced defense systems at a time when execution matters more than ever. We believe focus, ownership, and excellence are decisive advantages - and we're building a world-class team to turn bold ideas into real capability. 

This is a rare opportunity to join at an early stage, where you'll have significant ownership, collaborate with exceptional teammates, and make a direct, measurable impact on our mission and the future of the company - regardless of your function.  

Database/Python Generalist

Castelion is seeking a Database / Python Generalist to build and improve the Seeker Team’s calibration automation tooling, PostgreSQL infrastructure, and Python backend services. This role will make far-field calibration faster, more reliable, and easier to execute while enabling engineering teams to access the correct calibration data automatically.

You will work across database architecture, query optimization, data pipelines, and hardware-facing test systems, partnering with algorithm, ML, and test teams to improve existing systems and build scalable solutions. This is a hands-on engineering role focused on practical improvements that directly accelerate seeker development and testing.

Responsibilities

• Own calibration automation: Develop far-field calibration tooling that combines individual tests into an end-to-end suite runner with resume-from-failure capabilities.
• Build calibration data infrastructure: Develop Golden Calibration data systems and a Calibration Dependency Graph to support reliable, automated calibration workflows.
• Optimize PostgreSQL performance: Improve schemas, queries, indexes, partitioning, and data access patterns to accelerate calibration data products and visualization.
• Evolve database architecture: Design schemas, ORM models, and shared data types to support new requirements from algorithm and ML teams.
• Build reliable data pipelines: Develop ingestion and synchronization workflows with appropriate retry, idempotency, consistency, and conflict-handling strategies.
• Maintain production databases safely: Implement schema migrations, backfills, indexing changes, and data-retention, archival, and deletion policies.
• Develop Python services: Build and maintain production backend services, APIs, database utilities, and reusable data-access components.
• Support hardware-facing testing: Contribute to Python-based test systems and chamber-testing workflows to expand testing capacity and reduce calibration runtime.
• Improve existing systems pragmatically: Identify bottlenecks, implement targeted improvements, and avoid unnecessary redesigns.

Basic Qualifications

• Strong Python software engineering skills, including experience building production services and APIs.
• Demonstrated experience architecting PostgreSQL schemas for real-world applications and safely modifying production databases.
• Deep PostgreSQL expertise, including indexing, query planning, transactions, locking, and performance analysis.
• Experience using EXPLAIN and EXPLAIN ANALYZE to optimize real-world query patterns.
• Experience designing safe schema migrations, backfills, and concurrent index changes.
• Experience building reliable data-ingestion pipelines and multi-database synchronization systems.
• Experience with ORMs and direct SQL, with sound judgment about when to use each.
• Understanding of partitioning, batching, pagination, and efficient bulk reads and writes.
• Experience developing shared Python types, database models, and reusable data-access tools.

Preferred Skills and Experience

• Experience automating data-retention, archival, and deletion policies.
• Experience building calibration, test automation, or engineering data-management systems.
• Familiarity with hardware-facing Python test systems and chamber testing.
• Experience supporting algorithm development, machine learning, or other data-intensive engineering workflows.
• Experience designing dependency-aware data pipelines and systems that select the correct data products automatically.
• Ability to improve existing systems through targeted, measurable changes while maintaining reliability.

Castelion offers a generous benefits package. Please refer to the bottom of our Careers page for more details.  

Other Duties 

Please note this job description is not designed to cover or contain a comprehensive listing of activities, duties or responsibilities that are required of the employee for this job. Duties, responsibilities and activities may change at any time with or without notice. 

Additional Eligibility Requirements 

This position may require access to classified information or restricted U.S. Government sites, systems, or information, as determined by the Company and/or applicable U.S. Government requirements. If the position is so designated, your employment in the role may be contingent upon your ability to obtain and maintain the required U.S. Government security clearance or other government authorization, and to satisfy any citizenship or other eligibility requirements imposed by applicable law, regulation, executive order, or government contract requirements. You will be notified if and when such requirements apply. 

Affirmative Action/EEO Statement 

Castelion is an Equal Opportunity Employer. We are committed to providing equal employment opportunities to all applicants and employees without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, age, disability, genetic information, protected veteran status, or any other characteristic protected by applicable federal, state, or local law. 

Castelion is committed to providing reasonable accommodations to qualified individuals with disabilities throughout the application and hiring process. If you require a reasonable accommodation to complete an application, participate in the interview process, or otherwise participate in the hiring process, please contact hr@castelion.com. Requests for accommodation will be considered on an individual basis and handled in accordance with applicable law. 

Castelion is committed to fostering a workplace where employment decisions are based on qualifications, business needs, and the ability to perform the essential functions of the role, with or without reasonable accommodation. 

EAR/ITAR Requirements 

This position requires access to export-controlled information, and as such, employment (or hiring of a contractor) is contingent upon the candidate’s ability to access all applicable export-controlled information without additional export licensing being required by the Bureau of Industry and Security and/or the Directorate of Defense Trade Controls.