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.

Human Resources Manager

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.

Responsibilities

Site Leadership Partnership

• 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.

Employee Relations & Performance Management

• 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.

Non-Exempt Workforce Support

• 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.

Site Growth & Operations

• 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.

HR Operations

• 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.

Compliance & Risk Management

• 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.

Basic Qualifications

• 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 experience coaching managers through employee relations, investigations, corrective actions, and performance management.
• Deep understanding of wage and hour laws affecting hourly employees.
• Experience partnering directly with Operations leaders in fast-paced environments.
• Ability to manage multiple priorities with minimal direction.
• Excellent communication and relationship-building skills.

Preferred Skills and Experience

• Experience supporting a new facility launch or major site expansion.
• Experience in aerospace, defense, manufacturing, or other highly regulated industries.
• Multi-state HR experience.
• Experience with HRIS systems such as Rippling, Workday, UKG, or similar.
• PHR, SPHR, SHRM-CP, or SHRM-SCP certification.

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.

Benefits And Perks

All full-time employees are granted meaningful long-term equity, sharing in the company’s significant growth trajectory. We offer four (4) weeks of paid time off, ten (10) company-paid holidays, and comprehensive health benefits - including 100% employee-covered medical and strong dependent coverage, along with dental and vision plans. We also provide paid parental leave to support growing families, a $100 monthly fitness stipend to promote health and performance, and onsite EV charging for convenience. In addition, employees enjoy perks like catered meals, company-covered food during high-demand periods, and a fully stocked kitchen to stay fueled throughout the day.

While this position does not currently require a U.S government-issued security clearance, it may in the near future. Therefore, the ability to obtain and maintain a U.S. government–issued security clearance is required. U.S. citizenship is required, as only U.S. citizens are eligible for a security clearance.

Affirmative Action/EEO Statement

Employment with Castelion is governed on the basis of competence and qualifications and will not be influenced in any manner by race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability or any other legally protected status.