Senior Security Architect – Threat Modeling & Cloud Defense

Iridium; California (MO); Hybrid; USD 170,000 - 250,000; Full time

Benefits offered by this job

Hybrid work policy

Medical insurance

Dental insurance

Vision insurance

401(k) retirement plan

Paid time off

Paid holidays

Parental leave

Stock and bonus

Job summary

Iridium is seeking a Principal Security Engineer to design secure architecture from inception, conduct adversarial assessments, and guide threat modeling for a high-impact pre-launch service. You will influence design decisions, partner with engineering, and lead security initiatives in a hybrid work setting.

You will build threat models, perform red‑team assessments, and ensure secure identity integrations across SAML, OIDC, OAuth 2.0, WebAuthn, and CTAP, while mentoring teammates and shaping

Qualifications

• 10+ years of experience in network and information security, with depth in offensive or adversarial security; red team experience preferred.
• Strong applied expertise in AWS security fundamentals (IAM, VPC, misconfigurations).
• Hands-on understanding of identity protocols (SAML, OIDC, OAuth 2.0, WebAuthn, CTAP) and how flows can be attacked or strengthened.
• Ability to communicate security risk to engineers and non-technical stakeholders, including customers and partners.
• Experience as an individual contributor in a high ambiguity, high trust, small team environment.
• Excellent communication, able to convey complex topics clearly and adapt to different audiences.
• Ability to build relationships with senior leadership and provide constructive feedback.
• Analytical mindset to generate effective solutions and drive them to completion.
• Creativity and resourcefulness to make reliable decisions on new assignments.
• Thrives in a dynamic environment with shifting priorities.
• Proactive in sharing knowledge with others.

Responsibilities

• Analyze AWS-based cloud infrastructure, APIs, and services to identify attack paths and translate findings into defensive priorities.
• Advise on secure design decisions across cloud infrastructure and application logic early in development.
• Develop and maintain threat models and foster a threat-modeling culture in a small pre-launch team.
• Conduct or commission red-team style assessments across network, app, cloud, identity flows, and supply-chain vectors.
• Communicate security findings with business impact, guiding pragmatic prioritization and decisions.
• Evaluate integration of Iridium's service with partner identity systems (SAML, OIDC, OAuth 2.0, WebAuthn, CTAP).
• Identify weaknesses in these integrations and strengthen step-up authentication and assurance contexts.
• Serve as tier-2 security SME in partner or customer conversations; collaborate with engineering, product, and partner-facing teams.
• Help establish early security practices, lightweight processes, and standards for a pre-launch environment.
• Provide mentorship to engineers and future security team members.

Skills

Security engineering

AWS security

Red team

Threat modeling

Identity protocols

Clear communication

Job description

Iridium is seeking a Principal Security Engineer to design secure architecture from inception, conduct adversarial assessments, and guide threat modeling for a high-impact pre-launch service. You will influence design decisions, partner with engineering, and lead security initiatives in a hybrid work setting.

You will build threat models, perform red‑team assessments, and ensure secure identity integrations across SAML, OIDC, OAuth 2.0, WebAuthn, and CTAP, while mentoring teammates and shaping