Human Resources Manager

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 and technical excellence are decisive advantages - and we are building a team that can deliver real capability, not just concepts.

This is a rare opportunity to join at an early stage, where your work will directly shape critical systems, influence major technical decisions, and have immediate, real-world impact.

We are seeking a Human Resources Manager responsible for launching and supporting people operations of a new manufacturing facility during a period of rapid growth. This role is highly operational and partners directly with leadership to build a high-performing workforce, establish a strong employee culture, and ensure exceptional execution of day‑to‑day HR operations.

• Partner with leadership to execute workforce strategies that support production goals, organizational growth, and operational excellence.
• Coach and develop leaders to improve manager effectiveness, accountability, employee performance, and engagement.
• Provide data‑driven HR guidance by identifying workforce trends, risks, and opportunities that improve business outcomes.

• Lead complex employee relations matters and performance management activities, ensuring timely, consistent, and legally compliant resolutions.
• Strengthen manager capability through coaching on investigations, corrective actions, conflict resolution, and employee development.
• Foster a high‑performance culture by driving accountability, consistent policy application, and proactive resolution of workplace issues.

• Serve as the HR expert for a large non‑exempt manufacturing workforce, ensuring compliance with wage and hour laws, attendance, scheduling, and timekeeping practices.
• Analyze workforce metrics, including turnover, attendance, overtime, and engagement, to identify trends and implement operational improvements.
• Partner with leaders to proactively resolve workforce challenges that could impact productivity, staffing or employee retention.

• Support rapid site expansion by partnering with leaders to achieve hiring, onboarding, and workforce readiness objectives.
• Coordinate HR support for organizational growth, new production lines, shift expansions, and workforce changes while maintaining a consistent employee experience.
• Ensure company HR programs and initiatives are executed effectively and consistently across the Rio Rancho site.

• Execute core HR programs, including performance reviews, compensation, promotions, employee development, and policy administration with accuracy and timeliness.
• Partner cross‑functionally with Payroll, Benefits and Talent Acquisition to deliver exceptional employee support and operational efficiency.
• Utilize workforce data and HR metrics to identify opportunities for continuous improvement and inform business decisions.

• Ensure compliance with federal, New Mexico, and company employment requirements while minimizing organizational risk.
• Lead audits, investigations, documentation, and regulatory activities with accuracy, consistency, and timely execution.
• Partner with leaders and Environmental Health & Safety to proactively address workplace risks and maintain a compliant, safe work environment.

• Bachelor's degree in Human Resources, Business, or related field.
• 6+ years of progressive Human Resources experience.
• 3+ years supporting manufacturing, production, distribution, or other operational environments with significant non‑exempt populations.
• Strong…