Work on designing, implementing, testing, and shipping security and hardening features for Firefox, improving security architecture (cryptographic protocols, WebPKI, privilege isolation), and diagnosing stability, performance, and memory issues in a complex multithreaded, cross-platform codebase. Requires 3+ years in low-level systems programming with strong C/C++ proficiency, debugging skills, familiarity with web technologies, and interest or experience in Rust.

Work on Firefox Security to design, implement, test, and ship security features (including privilege isolation, cryptographic protocols, and WebPKI), diagnose multithreaded stability/performance issues, and collaborate across teams. Requires 3+ years in low-level systems programming with strong C/C++ proficiency and familiarity with web technologies and Rust. Role listed as Remote Sweden.

Work on designing, implementing, testing, and shipping security and hardening features for Firefox across multiple operating systems. Improve core security mechanisms (cryptographic protocols, WebPKI, security-sensitive web APIs), investigate and fix security issues, and diagnose stability, performance, and memory problems in a large multi-language codebase. Requires 3+ years in low-level systems programming with strong C/C++ skills and familiarity or interest in Rust.

Design, implement, test, and ship security and hardening features for enterprise Firefox users; improve core security architecture (cryptographic protocols, WebPKI, security-sensitive web APIs) and build privilege isolation. Diagnose and resolve stability, correctness, performance, and memory issues in a complex, multithreaded, cross-platform native codebase. Requires 3+ years of low-level systems programming experience with strong proficiency in C and/or C++ and familiarity with Rust and web technologies.

Work on designing, implementing, testing, and shipping security and hardening features for Firefox across multiple operating systems. Improve core security mechanisms (cryptographic protocols, WebPKI, security-sensitive web APIs), investigate and fix security issues, and diagnose stability, performance, and memory problems in a large, multithreaded codebase. Requires 3+ years in low-level systems programming with strong C/C++ proficiency and security fundamentals; familiarity with web technologies and Rust is desirable.

Join Firefox Security to build and improve security architecture across platforms (privilege isolation, cryptographic protocols, WebPKI, security-sensitive APIs). Responsibilities include designing, implementing, testing, and shipping security features; investigating security issues and fixing stability, performance, and memory problems in a multithreaded, cross-platform codebase. Requires 3+ years low-level/software systems experience, strong C/C++ proficiency, familiarity or interest in Rust and web technologies, and experience working with distributed teams. Salary range listed for Remote UK: £66,000–£87,000.

Work on designing, implementing, testing, and shipping security and hardening features for Firefox, improving security architecture (including cryptographic protocols and WebPKI), investigating and fixing security issues, and diagnosing stability, correctness, performance, and memory problems in a large, multithreaded, cross-platform codebase. Requires 3+ years of low-level systems programming experience, strong C/C++ proficiency, security knowledge, and familiarity with web technologies and Rust.

Work on Firefox Security to design, implement, test, and ship security features (privilege isolation, cryptography, WebPKI, security-sensitive web APIs), investigate and fix security issues, and improve reliability and performance in a complex, multithreaded, cross-platform codebase. Requires 3+ years in low-level systems programming with proficiency in C and/or C++ and familiarity or interest in Rust.

Mozilla seeks a Senior Security Engineer (Incident Responder) to monitor and mitigate attacks across products and services. Responsibilities include incident command, designing alerts/playbooks/automation, threat hunting, and managing SIEM/EDR/SOAR tooling. Requires 5+ years of incident response or SOC/PSIRT/CSIRT experience and hands-on experience with SIEM (Splunk/ELK/BigQuery), EDR, SOAR (Tines/Splunk SOAR), and cloud platforms. Hiring range for Remote Spain: €58,000–€77,000 per year.

Mozilla is hiring a Senior Security Engineer (Incident Responder) to monitor and mitigate attacks across products and services. Responsibilities include leading incident response lifecycle as incident commander, designing alerts/playbooks/automation for 24/7 response, threat hunting, triage, and post-mortem activities. Requires 5+ years in security incident management or SOC/PSIRT/CSIRT experience and practical expertise with SIEM (e.g., Splunk, ELK, BigQuery), EDR tools, SOAR platforms (e.g., Tines, Splunk SOAR), and cloud environments (GCP, AWS, Azure, Heroku).

Monitor and mitigate security incidents across Mozilla products; act as incident commander, design and maintain alerts/playbooks/automation, conduct threat hunting and threat intelligence triage, and participate in on-call rotation. Requires 5+ years managing security incidents or SOC/PSIRT/CSIRT experience and expertise with SIEM (Splunk/ELK/BigQuery), EDR, SOAR (Tines/Splunk SOAR), and cloud platforms (GCP/AWS/Azure).

Mozilla is hiring a Senior Security Engineer (Incident Responder) to identify and respond to security incidents at scale, act as incident commander, design and maintain alerts, automated actions, playbooks and escalation workflows, conduct threat hunting, triage threat intelligence, and participate in a 24/7 on-call rotation. Required experience includes 5+ years in incident management or SOC/PSIRT/CSIRT roles and proficiency with SIEM (Splunk preferred), EDR, SOAR platforms, and cloud platforms (GCP, AWS, Azure, Heroku).

Mozilla is hiring a Senior Security Engineer / Incident Responder to monitor and mitigate attacks across Mozilla products and services. Responsibilities include acting as incident commander, maintaining alerts, automation, playbooks and escalation workflows, conducting threat hunting, triaging threat intelligence, and participating in a 24/7 on-call rotation. Requires 5+ years experience in incident management/SOC roles and proficiency with SIEM (Splunk preferred), EDR, SOAR, and cloud platforms. Salary range for Remote Sweden provided in posting.

Mozilla is hiring a Senior Security Engineer (SecOps) to monitor and mitigate security incidents, act as incident commander, develop alerts/automation/playbooks, conduct threat hunting and threat intelligence, and partner with stakeholders. Requires 5+ years of incident management or SOC/PSIRT/CSIRT experience and hands-on expertise with SIEM (e.g., Splunk, ELK, BigQuery), EDR, SOAR platforms, and cloud environments (GCP, AWS, Azure, Heroku).

Mozilla is hiring a Senior Security Engineer (SecOps) to monitor and mitigate attacks, act as incident commander, design alerts/playbooks/automations, conduct threat hunting, and manage threat-intelligence workflows. Requires 5+ years in incident response or SOC/PSIRT/CSIRT roles, strong SIEM (Splunk/ELK/BigQuery) and EDR experience, familiarity with SOAR (Tines, Splunk SOAR), cloud platform experience (GCP/AWS/Heroku/Azure), and participation in an on-call rotation.

Mozilla is hiring a Senior Security Engineer (Incident Responder) to identify and respond to security incidents at global scale, act as incident commander, build alerts/playbooks/automations, conduct threat hunting, and work on-cloud and endpoint telemetry. Requires 5+ years of relevant incident response/SOC experience and proficiency with SIEM (Splunk preferred), EDR, and SOAR platforms.

Remote (US) Senior Security GRC Engineer role at Mozilla. Responsible for maintaining and maturing the ISMS (SoA, risk treatment plans, Management Review Meetings), supporting ISO 27001 and SOC 2 Type 2 audit execution and readiness, authoring audit narratives (e.g., SOC 2 System Description), leading security policy creation and review cycles, tracking gaps/remediation, and partnering with Engineering, IT, Legal, Privacy, People, and product leadership. Requires 5 years of relevant experience. Posted salary ranges for US tiers: $139,000–$218,000 USD per year (varies by tier).

Work within Mozilla’s Security GRC function to maintain the ISMS (SoA, risk treatment, MRM), support ISO 27001 and SOC 2 Type 2 audit execution and readiness, lead security policy creation and review cycles, track remediation efforts, support internal audits, and partner with engineering, legal, privacy, and product teams to drive control ownership and audit evidence.

Maintain and mature Mozilla's ISMS (SoA, risk treatment plans, MRMs); support ISO 27001 and SOC 2 Type 2 audits (scope, evidence, auditor interviews, findings remediation); lead security policy program; support internal audits and compliance scaling; partner with Engineering, IT, Legal, Privacy, People and product teams. Requires ~5 years in information security/GRC with hands-on experience in ISO 27001 and SOC 2.

The Senior Security GRC Engineer will own ISMS activities (SoA, risk treatment plans, management reviews), support ISO 27001 and SOC 2 Type 2 audits (scope, evidence, auditor interviews), drive security policy creation and review cycles, track gaps and remediation, and partner with Engineering, IT, Legal, Privacy, and People teams. The role requires ~5 years' experience in information security/GRC and deep familiarity with ISO 27001 and SOC 2.