At Astranis, a Security Engineer plays a vital role in protecting the next generation of space infrastructure. Astranis builds and operates small, low-cost telecommunications satellites to provide internet access to underserved regions across the globe. Because these satellites operate in geostationary orbit (GEO) and act as critical infrastructure for entire nations, security is not an afterthought—it is a core engineering requirement. A security failure in orbit cannot be resolved with a physical hardware swap, making proactive, rigorous security engineering essential to the company's survival and mission success.

As a Security Engineer—whether specializing in Product Security, Red Teaming, or Security Operations—your work directly impacts the physical and digital integrity of the spacecraft, ground stations, and mission control networks. You will collaborate closely with flight software engineers, hardware designers, and mission operations teams to design secure architectures, perform threat modeling, conduct penetration tests, and build automated security controls. The challenge lies in balancing robust security with the severe resource constraints of space hardware, such as limited compute power, strict power budgets, and high-latency communication links.

This role requires a rare blend of deep technical curiosity, systems-level thinking, and a mission-first mindset. You will work on fascinating engineering problems that span embedded systems security, cryptographic protocol design, cloud-based mission control infrastructure, and global telecommunications networks. If you are excited by the prospect of defending space-bound hardware and securing global communications from sophisticated adversaries, this position offers an unmatched opportunity for impact.

The questions you will encounter during the Astranis interview process are designed to evaluate your practical security engineering skills, systems-level thinking, and ability to operate under constraints. Rather than testing for rote memorization, interviewers focus on your problem-solving methodology and how you apply security principles to complex, real-world scenarios.

The following representative questions are grouped by core technical domains to help you structure your preparation.

Product Security & Cryptography

This category focuses on your ability to design secure communication protocols, implement cryptographic controls, and protect software running on both the spacecraft and ground infrastructure.

• How would you design a secure boot process for an embedded flight computer with limited processing power and storage?

Preparing for an interview at Astranis requires a shift in mindset compared to traditional software companies. Because you are securing physical spacecraft and critical communications infrastructure, your technical decisions carry immense real-world weight. You must demonstrate that you can think deeply about physical, hardware, and network constraints while maintaining a high security bar.

When preparing, focus on mastering the following core evaluation criteria that Astranis interviewers use to assess candidates:

Embedded & Systems Security Knowledge – You must demonstrate a deep understanding of how software interacts with hardware. This includes operating system internals, memory management, secure boot processes, and low-level cryptographic implementations.

Threat Modeling & Risk Assessment – Interviewers want to see how you systematically analyze a system to find weak points. You should be able to break down a complex architecture, identify trust boundaries, enumerate threats, and propose practical, risk-prioritized mitigations.

Practical Problem-Solving & Coding – You should be comfortable writing clean, secure, and efficient code (typically in C, C++, Rust, Python, or Go). You will be evaluated on your ability to solve algorithmic problems, write secure code, and identify vulnerabilities in existing code blocks.

Mission-First Collaboration – At Astranis, security engineers do not work in an isolated silo. You must show that you can collaborate effectively with multidisciplinary teams, communicate complex security concepts clearly to non-security engineers, and find pragmatic solutions that do not block engineering velocity.

The interview process at Astranis is thorough, technical, and highly collaborative. It is designed to evaluate both your deep domain expertise and your alignment with the company's fast-paced, mission-driven culture. You will interact with several members of the security, software, and hardware engineering teams, giving you a comprehensive view of the people and projects you will be working with.

The process typically begins with an initial conversation with a recruiter to discuss your background, career goals, and interest in space technology. This is followed by a technical screen, which usually involves a coding session or a deep-dive discussion into systems security and threat modeling. If you pass this stage, you will be invited to the virtual or on-site interview loop, which consists of multiple focused technical rounds, a system design session, and conversations centered on collaboration and culture fit.

Throughout the process, the hiring team looks for candidates who are passionate about solving hard, unprecedented problems and who exhibit high ownership. The atmosphere is intellectually stimulating and rigorous, but supportive—interviewers genuinely want to see how you think and how you approach complex, ambiguous challenges.

The timeline above outlines the standard progression from your initial contact to a potential offer. Candidates should use this visual guide to pace their preparation, ensuring they allocate sufficient time to practice coding, review cryptography fundamentals, and run through mock threat modeling scenarios before the intensive onsite rounds. While the exact duration can vary based on scheduling, the entire process is designed to move efficiently.

To succeed in the Astranis security interview, you must perform well across several distinct technical and architectural evaluations. Below is a detailed breakdown of the primary areas you will be tested on, including what strong performance looks like and the specific concepts you should master.

Embedded Systems & Firmware Security

Securing the spacecraft requires a deep understanding of embedded systems, firmware, and low-level software. You must show that you understand how to protect devices that run on bare metal or Real-Time Operating Systems (RTOS) where traditional security agents and enterprise tools cannot be installed.

Be ready to go over:

• Secure Boot and Chain of Trust – How to design bootloaders that cryptographically verify firmware signatures before execution, ensuring only authorized code runs on the flight computer.
• Memory Safety and Protection – Techniques for preventing and mitigating memory corruption vulnerabilities in C/C++ environments, including proper use of memory protection units (MPUs).
• Hardware-Based Security Features – Utilizing hardware security modules (HSMs), secure elements, and Trusted Platform Modules (TPMs) to secure cryptographic keys.
• Advanced concepts (less common) – Side-channel analysis mitigation, fault injection defense (such as clock or voltage glitching), and reverse engineering firmware binaries.

Example scenarios:

• Designing a secure firmware update mechanism over a low-bandwidth, high-latency satellite communication link.
• Auditing a piece of C-based telemetry-parsing code to identify and patch potential buffer overflow vulnerabilities.

Cloud & Ground Station Security

The satellite is only one part of the system; it must communicate with ground stations (teleports) and cloud-based mission control infrastructure. Securing these ground segments is critical to preventing unauthorized access to the space fleet.

Be ready to go over:

• API and Protocol Security – Designing secure, authenticated, and rate-limited APIs for transmitting telemetry and command data between the cloud and physical ground stations.
• Identity and Access Management (IAM) – Implementing zero-trust architectures, multi-factor authentication, and strict least-privilege access controls for mission operators.
• Network Segmentation and Firewalls – Isolating highly sensitive mission control networks from corporate IT networks and public internet interfaces.
• Advanced concepts (less common) – Software-Defined Radio (SDR) security, securing containerized workloads (Kubernetes) in remote ground environments, and defending against satellite uplink spoofing.

Example scenarios:

• Architecting a secure, automated pipeline for deploying software updates to remote ground stations distributed globally.
• Building a detection system to identify unauthorized or anomalous API calls originating from ground station networks.

Threat Modeling & Secure Design

A core responsibility of a Security Engineer is to help other engineering teams design secure systems from the ground up. You will be evaluated on your ability to systematically analyze a system design, identify risks, and propose practical mitigations.

Be ready to go over:

• Threat Modeling Frameworks – Applying structured methodologies like STRIDE to decompose a system, identify threat actors, and map out attack vectors.
• Trust Boundaries – Identifying where data crosses from untrusted zones (e.g., public internet, customer portals) to trusted zones (e.g., flight control systems).
• Fail-Safe and Resilient Architecture – Designing systems that fail securely without compromising the physical safety or availability of the spacecraft.
• Advanced concepts (less common) – Threat modeling physical security threats to ground teleports, and assessing risks associated with space-specific protocols (like CCSDS).

Example scenarios:

• Threat modeling a new web-based portal that allows customers to monitor their dedicated satellite payload bandwidth.
• Conducting a architectural security review of a proposed peer-to-peer communication protocol between multiple satellites.