Human Resources Manager

Rio Rancho, United States | Posted on 08/06/2026

Castelion was founded to restore America’s ability to field advanced weapons at speed and scale. Inspired by the engineering urgency of the WWII and Apollo eras, we combine rapid iteration, vertical integration, and scalable manufacturing to deliver affordable, high-performance strike systems. Our mission: rebuild industrial agility to strengthen national security and outpace evolving threats.

About the Role:

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.

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.
• Employee Equity:
  Meaningful equity forall full-time employees - share value has increased 150x in three years
• Personal Time Off:
  Four (4) weeks of paidtime off to unplug, reset, and come back sharp velocity matters,burnout doesn't
• Medical:
  We offer plans at 100% employee covered and 80% of dependent coverage
• Dental & Vision:
  We cover 90% employees and 80% for dependents to ensure you and your family have access to quality preventive and ongoing care
• FSA/HSA:
  To support long-term health and financial resilience, we offer FSA and HSA options that allow employees to set aside pre-tax dollars for eligible medical and dependent care expenses
• Retirement: 401k plan offered to support long term financial growth along side high-impact, high-velocity work
• Paid Parental Leave:
  We support growing families with meaningful time to bond and recover. Birthing parents are eligible for up to 10 weeks of paid leave, while non-birthing parents may take up to 4 weeks of paid leave. This time can be usedfor pre-natal care, pregnancy, childbirth, and related medical needs ensuring every parent has the support they need during this important life moment.
  8-weeks of paid parental leave for all parents. Additional paid pregnancy leave for CA employees
• Meals & Catering:
  Frequently catered lunches and team meals, plus company-covered meals when extra timeor effort is required
• Snacks & Beverages:
  Fully stocked kitchen with unlimited snacks and drinks to keep you fueled throughout the day
• Performance & Fitness: $100 monthly fitness stipend to support peak performance and health, both insideand outside of work
• EV Charging:
  Onsite electric vehicle charging available for employees