“the whole is greater than the sum of its parts”

Lindsey Britt

President & CEO

President/CEO, founded and led Castalia Systems since 2011. She holds a Bachelor of Science in Business and Marketing and is a Certified Project Management Professional (PMP). She has years of experience across the Business Development, Program Management, Marketing and Human Resources spectrum ranging from start-up companies through major Defense Contractors. Prior to founding Castalia Systems, as a Business Development Manager, Ms. Britt supported the growth of a large defense company through the capture of multiple hundred+ million dollar business, covering over 30 locations worldwide.

Ms. Britt founded Castalia Systems after serving as a Program Manager, Business Development Manager, and Account Manager helping to grow an 8(a) small business to reach its potential. Her focus and passion is managing and growing Intelligence Community (IC) support, which has remained a significant focus throughout the growth of Castalia Systems.

Zachary Mann

Chief Operating Officer
Chief Financial Officer

Co-founded Castalia Systems in 2011. He earned a Master of Science in Electrical Engineering from the University of Southern California and a Bachelor of Science in Electrical Engineering from the University of Delaware. Mr. Mann is a retired Airforce Lieutenant Colonel and has over twenty years of experience in leading personnel.

Mr. Mann help found Castalia Systems after serving over seven years as the Director of Operations and Program Manager for an 8(a) small business. As a certified PMP, he managed numerous multi-million dollar programs during his tenure. He has supported numerous clients worldwide to include SOCOM, INSCOM, EUCOM, PACOM and the DJC2 JPO.

Mr. Mann, during his military service, served in numerous tactical communication units in Germany, Korea and Florida both on active duty and in part-time status. He served as the deployed commander for deployments to the Philippines, Pakistan, and Albania. He also served as a certified acquisition officer in Los Angeles, CA for the Space and Missile Center (SMC). In addition, he co-authored JCSE’s five year modernization plan to provide a roadmap for converged IP and similar technology for tactical communication applications.

Gary Doss, PhD

Chief Technology Officer
Chief Information Officer

Dr. Doss joined the Castalia family in 2017 to oversee the delivery of technical solutions and customer offerings. He holds a PhD, Bachelor, and Masters degrees in Computer Science, and Information Systems specializing in both Cyber & Information Security and Software Development. Dr. Doss brings years of experience from the Intelligence Community (IC), Department of Defense (DoD), and Research and Development. Dr. Doss has managed extremely large business units and programs, to include the management of multiple Defensive Cyber programs protecting entire federal agencies. Dr. Doss holds several certifications such as PMP, CISSP, CGEIT, CISM, and CISA.

During his career with the US Government, the US Navy as a Cryptologic Warfare and Engineering Duty Officer, and through Industry, he has supported operations and clients in over 20 countries, supported multiple COCOMs in 5 AORs, and has experience in multiple intelligence disciplines such as HUMINT, SIGINT, and GEOINT. Dr. Doss expertise in science and engineering has allowed him to develop, manage, and consult on advance research and development projects in a wide range of disciplines. Examples include advanced Artificial Intelligence systems, Aircraft Safety systems, Advanced Intrusion Detection, Satellite Communications, Insider Threat Detection, and Cryptographic Systems.


Working at Castalia Systems is a rewarding and exciting opportunity. Explore the current and future opportunities of joining a growing business that puts its employees first.