Principal Engineer, Cybersecurity

T-Mobile•Bellevue, WA

About The Position

This role protects digital assets by ensuring robust cybersecurity across software, systems, and infrastructure. It conducts device security assessments, code reviews, and vulnerability testing to identify and mitigate risks, working with engineering teams and OEMs to implement security measures for mobile and IoT devices, including CPEs, hotspots, trackers, routers, and modems. Success is measured by the effectiveness of security controls and the reduction of vulnerabilities. The work strengthens organizational resilience against cyber threats and safeguards business operations and customer data. The role leads device security assessments and penetration testing, develops proactive security strategies, and integrates security practices into hardware and software development and deployment. It also conducts digital forensics on compromised or suspect devices, helps establish the device security assessment methodology and tooling roadmap, and mentors junior and mid-level security engineers. Other duties and projects may be assigned by business management.

Requirements

Bachelor’s degree plus 7 years of related work experience, or an advanced degree plus 5 years of related experience.
Degree in Computer Science, Information Technology, or an acceptable related area of study.
3–5 years of hands-on experience conducting device security assessments and testing on IoT devices, routers, modems, or similar embedded platforms.
3–5 years of proficiency with security tools such as Ghidra, IDA Pro, dotPeek, Burp Suite, Nmap, hashcat, and OllyDbg.
3–5 years of hands-on knowledge of 4G LTE and 5G architecture (RAN and Core), including cloud environments and containerized applications.
Required knowledge or capability in artificial intelligence, leadership, collaboration, problem solving, strategic thinking, cybersecurity, escalation management, security automation, security engineering, security incident management, stakeholder management, and threat modeling.
At least 18 years of age.
Legally authorized to work in the United States.

Nice To Haves

3–5 years of proficiency in Python, C++, C#, PHP, and shell scripting, including building scalable systems and automating workflows; familiarity with AI tools such as ChatGPT and Claude.
7–10 years conducting security assessments and vulnerability testing to identify and mitigate risks in digital environments.
7–10 years developing and implementing cybersecurity measures across mobile and IoT devices, cloud services, and network technologies.
7–10 years leading and collaborating with engineering teams to improve security postures and strategic cybersecurity initiatives.
Certified Information Systems Security Professional (CISSP) certification.
Certified Information Security Manager (CISM) certification.
Certified in Risk & Information Systems Control (CRISC) certification.

Responsibilities

Lead end-to-end device security assessments and penetration testing across IoT devices, CPEs, hotspots, trackers, routers, and modems to identify and mitigate risks.
Develop proactive device security measures, solutions, and strategies to improve security across technologies.
Collaborate with device engineering teams and OEMs to integrate security into hardware and software development, including deployment processes.
Conduct digital forensics on compromised or suspect devices to determine root cause, scope, and attacker methodology, partnering with threat response teams.
Drive strategic security initiatives to protect against cyber threats and support compliance with security standards.
Define and evolve T-Mobile’s device security assessment methodology, requirements, standards, and tooling roadmap.
Mentor and upskill junior and mid-level security engineers on device security techniques and best practices.
Perform other duties or projects as assigned by business management.

Benefits

Competitive base salary and compensation package.
Annual stock grant and employee stock purchase plan.
401(k) and access to year-round money coaches.
Annual bonus or periodic sales incentive or bonus, as applicable to the role.
Medical, dental, and vision insurance.
Flexible spending account.
Paid time off and up to 12 paid holidays.
Paid parental and family leave.
Family-building benefits, backup care, enhanced family support, and childcare subsidy.
Tuition assistance and college coaching.
Short- and long-term disability coverage, voluntary AD&D and accident coverage, voluntary life insurance, voluntary disability insurance, and voluntary long-term care insurance.
Mobile service and home internet discounts, for eligible employees.
Pet insurance, for eligible employees.
Commuter and transit programs, for eligible employees.