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# Senior Mobile & Backend Security Engineer

- **Company:** United States Digital Space Llc
- **Location:** San Francisco, CA, United States
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** Application Programming Interfaces (APIs), Android Software Development, Code Review, Ruby, Mobile Security, Backend
- **Published:** November 7, 2026
- **Apply:** https://www.juju.com/job/28_25304_a7ff4aabab9874f0e3291987a2fe72bb

## About the Role

United States Digital Space LLC is seeking a Sr. Full Stack Application Security Engineer with deep mobile security expertise. This hands-on role partners with mobile, backend, and platform teams to prevent and remediate security issues across iOS, Android, APIs, and backend systems.

Expect architecture reviews, secure design influence, and security-focused delivery without slowing velocity. Strong mobile threat modeling, testing, and code review skills are essential, with proficiency in Ruby