Embedded Software Engineer Intern - Fall 2026

Castelion Corporation • Torrance, CA

12d

About The Position

Castelion is seeking motivated and talented Embedded Software Engineering interns for Fall 2026. You'll help create the software that drives and simulates our missile systems, from low-level firmware on microcontrollers to high-level integration and testing tools. You'll work alongside experienced embedded, hardware, and flight systems engineers to design, implement, test, and debug real systems in the loop. You won't be writing throwaway code; your contributions will directly support our rapid prototyping and real-world tests.

Requirements

• Currently pursuing a BS or MS in Computer Engineering, Electrical Engineering, Computer Science, or a related technical field
• Rising junior, senior, or graduate student at the time of the internship
• Strong C/C++ programming skills for embedded systems
• Experience with microcontrollers or SoCs (ARM, AVR, MSP430, PIC, etc.)
• Familiarity with developing in bare-metal or RTOS environments
• Understanding of board bring-up and debugging fundamentals
• Some familiarity with common protocols: SPI, I2C, CAN, UART, Ethernet, etc.
• U.S. Person status required (due to ITAR regulations)

Nice To Haves

• Experience integrating analog/digital hardware with firmware
• Familiarity with missile systems, defense technology, or aerospace components.
• Strong interest in working in a startup environment with high-impact projects.

Responsibilities

• Develop, test, and debug low-level firmware for embedded systems and flight hardware
• Write and integrate device drivers for sensors, actuators, and missile subsystems
• Bring up new hardware, test boards, and debug at the intersection of electrical and software layers
• Collaborate cross-functionally with hardware, GNC, and flight test teams to ensure robust integration
• Participate in design reviews, hardware-in-the-loop tests, and on-the-bench bring-up and validation
• Document your work clearly and share learnings to improve team knowledge and future designs

Benefits

• Mentorship from engineers who have shipped systems under tight timelines
• Housing or relocation stipends may be available to help offset temporary living expenses

What This Job Offers

• Career Level: Intern
• Education Level: No Education Listed