Senior Security Engineer, Web Crypto & Browser Platform

Mozilla; Town of Belgium (WI); On-site; USD 63,941 - 84,493; Full time

Benefits offered by this job

Performance bonus

Health/dental/vision coverage

Retirement contributions

Wellness days

Birthday holiday

Job summary

Mozilla is seeking a security-focused software engineer to advance Firefox’s security architecture, cryptography stack, and WebPKI. You will design and ship web platform security features, collaborate with teams across Mozilla, and help improve browser reliability, performance, and memory efficiency.

The role emphasizes debugging multi-threaded native applications, contributing to technical design reviews, and growing in browser security, cryptography, and systems programming while working with

Qualifications

• Experience in software engineering with proficiency in C/C++ and cryptographic principles.
• Experience building and maintaining complex software systems in large-scale or security-sensitive environments.
• Strong debugging and problem-solving skills in multi-threaded native applications.
• Collaborative communicator able to work with distributed teams and explain technical concepts clearly.
• Growth mindset with curiosity to deepen browser security, cryptography, and systems programming.
• Familiarity with web technologies and Rust; comfortable working in large, multi-language codebases.

Responsibilities

• Advance Firefox security architecture and cryptography stack focusing on WebPKI and security-sensitive web APIs.
• Design and implement web platform security features in collaboration with teammates and the broader web community.
• Improve browser reliability, performance, and memory efficiency by analyzing and resolving issues in a multi-threaded browser environment.
• Collaborate on security initiatives, debug root causes, and implement long-term solutions with engineers across teams.
• Contribute to technical design and planning through reviews and discussions on security-related projects.

Skills

C/C++

Security fundamentals

Multi-threaded systems

Debugging skills

Collaborative communication

Rust familiarity

Job description

Mozilla is seeking a security-focused software engineer to advance Firefox’s security architecture, cryptography stack, and WebPKI. You will design and ship web platform security features, collaborate with teams across Mozilla, and help improve browser reliability, performance, and memory efficiency.

The role emphasizes debugging multi-threaded native applications, contributing to technical design reviews, and growing in browser security, cryptography, and systems programming while working with