HIMARS Specialist

About Castelion

Castelion is bringing a new approach to defense development and production: one that focuses on short, iterative design cycles, rapid testing in development, and modern commercial manufacturing strategies for production 're designing, building, and testing next generation long range strike weapons systems to give America and its Allies a definitive edge and deter future conflicts.

The HIMARS Specialist will serve as Castelion's internal subject matter expert (SME) on HIMARS employment, operations, and tactical integration. This individual will translate firsthand operational experience into actionable guidance for engineering, manufacturing, testing, and customer engagement teams.

You will play a critical role in ensuring our systems are intuitive, survivable, rapidly employable, and aligned with how warfighters actually operate.

• Serve as the internal SME on HIMARS operations, tactics, techniques, and procedures (TTPs)
• Provide operator-informed input into system architecture, human-machine interface (HMI), mobility concepts, and reload workflows
• Advise engineering teams on real-world constraints including crew ergonomics, field maintenance, deployment timelines, and survivability considerations
• Support design reviews to ensure operational realism is embedded in system decisions
• Participate in field tests, live fire events, and mobility demonstrations to evaluate usability and mission flow
• Assist Business Development and Program teams with customer engagement, CONOPS development, and operational briefings
• Develop training concepts and documentation rooted in real operational experience
• Identify capability gaps and improvement opportunities based on firsthand system use

• Prior experience operating the M142 HIMARS in an operational military environment
• Deep understanding of HIMARS crew operations, mission planning, reload procedures, and fire mission execution
• Experience in deployed, training, or live-fire environments
• Ability to communicate operational insights clearly to engineering and technical teams
• Active U.S. security clearance or ability to obtain one

• Experience serving as Section Chief, Platoon Sergeant, Fire Direction Specialist, or similar leadership role
• Instructor or evaluator experience within a HIMARS unit
• Exposure to joint fires integration and coordination with higher-echelon fire control systems
• Familiarity with modern digital fire control and targeting workflows
• Experience supporting acquisition, test, or modernization efforts

All employees are granted long-term stock incentives as part of their employment as Castelion. All employees receive access to comprehensive medical, vision, and dental insurance, and the company offers three weeks of paid time off per year.

Bias to Action and Creative Problem Solving
. Desire and experience questioning assumptions in ways that lead to breakthrough ideas that are ultimately implemented. Successfully bring in applicable processes/concepts/materials from other industries to achieve efficiency gains. Ability to personally resolve minor issues in development without requiring significant support.

High Commitment, High Initiative
. A successful candidate will have a genuine passion for Castelion's mission and consistently look for ways to contribute to the company's technical goals and prevent hardware blockers. Ability to work in a fast paced, autonomously driven, and demanding atmosphere. Strong sense of accountability and integrity.

Clear Communicator
. Proactively communicates blockers. Trusted in previous roles to be voice of company with regulators, suppliers, gate keepers and customers. Capable of tactfully managing relationships with stakeholders to achieve company-desired outcomes without compromising relationships. Emails, IMs and verbal interactions are logical, drive clarity, and detailed enough to eliminate ambiguity.

• To conform to U.S. Government export regulations, applicant must be a (i) U.S. citizen or national, (ii) U.S. lawful, permanent resident (aka green card holder), (iii) Refugee under 8 U.S.C. § 1157, or (iv) Asylee under 8 U.S.C. § 1158, or be eligible to obtain the required authorizations from the U.S. Department of State.

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.