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.

Senior IR Seeker Systems Engineer

The Senior IR Seeker Systems Engineer will lead the architecture and development of advanced infrared seeker systems. This role owns the seeker from initial concept through production, balancing performance, cost, manufacturability, and testability to deliver step-function improvements over existing systems.

Responsibilities

• Lead end-to-end development of IR seeker architecture (hardware & software), establishing the baseline for next-generation systems
• Drive rigorous trade studies across performance, cost, size, and risk, including acquisition/tracking models and detailed error budgets
• Evaluate and optimize seeker performance across thermal environments (MWIR/LWIR), including radome integration and system-level impacts
• Own execution strategy - identify key vendors, define SOWs, and partner internally to align staffing, requirements, and manufacturability targets
• Ensure designs deliver a clear performance-per-cost advantage and are scalable to production, while effectively communicating progress and results to leadership and customers

Basic Qualifications

• Bachelor's or Master's degree in Electrical Engineering, Physics, Aerospace Engineering, or a related technical field
• Direct experience working on IR missile seeker systems
• Strong systems engineering background across both hardware and software domains
• Experience with IR sensing modalities (e.g., mid-wave and/or long-wave IR), tracking, and guidance concepts
• Ability to develop and present polished, technically rigorous materials to customers and stakeholders

Preferred Skills and Experience

• Experience taking seeker or similar electro-optical systems from concept through production
• Background in modeling, simulation, and trade study development for high-performance systems
• Familiarity with radome design, thermal environments, and integration challenges
• Experience working with external vendors and managing technical deliverables

Additional Requirements

• Ability to put in extended hours, including evenings and weekends, when required to meet aggressive timelines
• This role is based in Allen, TX and requires full-time onsite presence

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.