Embedded Flight Security Engineer: Cryptography

Front Door Defense; Torrance, Northern (CA, KY); Hybrid; USD 150,000 - 200,000; Full time

Job summary

Castelion is building next-generation defense software. As a Software Security Engineer, you will design cryptographic foundations across embedded flight software and hardware, owning encryption, code signing, secure boot, and key management.

You will collaborate with embedded, avionics, and infrastructure teams to integrate security from manufacturing provisioning to flight operations in constrained environments.

Qualifications

• Bachelor's degree in Computer Science, Computer Engineering, Electrical Engineering, or related STEM field.
• 3+ years of professional software engineering experience with exposure to cryptography or security engineering.
• Experience implementing encryption, authentication, or digital signature systems in C, C++, Rust, or similar languages.
• Strong understanding of cryptographic fundamentals (PKI, TLS, key exchange, hashing, signatures).
• Experience working in Linux-based or embedded environments.

Responsibilities

• Secure Boot & Root of Trust: design and implement secure boot chains, hardware-backed root of trust mechanisms, and firmware verification processes for embedded flight systems.
• Cryptography & Encryption: develop and integrate cryptographic protocols and libraries for embedded and distributed systems.
• Code Signing & Update Security: own software signing infrastructure and verification workflows to ensure authenticity and integrity of firmware, flight software, and field updates.
• Key Management & Provisioning: design secure key generation, storage, rotation, and provisioning systems across development, manufacturing, and deployed environments.
• Secure Communications: implement and review authenticated and encrypted communication channels between vehicle, ground systems, and internal subsystems.
• Threat Modeling & Hardening: conduct threat modeling and security reviews across the software stack; identify vulnerabilities and mitigate accordingly.
• Cross-Functional Integration: partner with embedded, avionics hardware, and infrastructure teams to embed security into system architecture from design to deployment.

Skills

Applied cryptography

C/C++/Rust

Linux/Embedded

Secure boot

Education

Bachelor's degree in CS/CE/EE

Job description

Castelion is building next-generation defense software. As a Software Security Engineer, you will design cryptographic foundations across embedded flight software and hardware, owning encryption, code signing, secure boot, and key management.

You will collaborate with embedded, avionics, and infrastructure teams to integrate security from manufacturing provisioning to flight operations in constrained environments.