Embedded Flight Security Engineer — Cryptography & Secure Boot

Cantos Ventures; Torrance (CA); On-site; USD 140,000 - 190,000; Full time

Benefits offered by this job

Stock incentives

Medical, Vision, Dental insurance

Paid time off

Job summary

Castelion is seeking a Software Security Engineer to build cryptographic foundations that secure our flight systems. You will own encryption, code signing, secure boot, and key management across embedded platforms, ensuring integrity, authenticity, and confidentiality of mission-critical systems.

You will collaborate with embedded, avionics, and infrastructure engineers to embed security from manufacturing provisioning through flight operations, translating cryptographic principles into

Qualifications

• Bachelor's degree in CS/CE/EE or related STEM field.
• 3+ years of professional software engineering with exposure to applied cryptography or security engineering.
• Experience implementing encryption, authentication, or digital signatures 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 for firmware and flight software.
• Key Management & Provisioning: design secure key generation, storage, rotation, and provisioning across environments.
• Secure Communications: implement and review authenticated and encrypted channels between vehicle, ground systems, and internal subsystems.
• Threat Modeling & Hardening: conduct threat modeling and security reviews across the software stack.
• Cross-Functional Integration: partner with teams to embed security into system architecture from design to deployment.

Skills

Applied cryptography

Software engineering

C/C++

Rust

Embedded/Linux

Education

Bachelor's degree in STEM

Tools

TLS Libraries

Code signing pipelines

Embedded toolchains

Job description

Castelion is seeking a Software Security Engineer to build cryptographic foundations that secure our flight systems. You will own encryption, code signing, secure boot, and key management across embedded platforms, ensuring integrity, authenticity, and confidentiality of mission-critical systems.

You will collaborate with embedded, avionics, and infrastructure engineers to embed security from manufacturing provisioning through flight operations, translating cryptographic principles into