Senior Security Engineer
Department of War and Fortune 500s, our platform runs on-premises and in private clouds, delivering secure messaging, file sharing, workflow automation, audio/screenshare, and project management all with full data and operational control. Mattermost powers high-stakes workflows across mission planning, real-time, real-world operations, DevSecOps, incident response, and cyber defense enabling secure collaboration from tactical edge and DDIL environments to enterprise HQ. Teams operate across web, desktop, and mobile, with embedded interoperability for Microsoft Teams, Outlook, and Microsoft 365.

We are hiring a Senior Security Engineer to protect the people, infrastructure, and tooling that goes into building and hosting Mattermost. This is a hands-on, high-impact role at the intersection of enterprise security engineering, cloud information security, and AI-enabled threat response.

Fully remote, globally distributed team no commute, genuine flexibility
As a Senior Security Engineer, you will lead the design and implementation of security tooling,



harden our cloud and IT infrastructure, and serve as a key responder to incidents. Lead security and IT projects to enhance the security posture of infrastructure and the company
Conduct threat hunting across cloud and endpoint environments using a Zero Trust framework
Administer company-wide IAM and security monitoring infrastructure
Explore and implement AI/automation in detection, analysis, and response pipelines
Bachelor s degree in Computer Science or a related field, or significant professional security experience
Experience with SIEM platforms and security monitoring systems
Experience with cloud security controls across AWS, GCP, and/or Azure
Strong knowledge of Linux systems and Kubernetes/Docker environments
Experience with IAM solutions and infrastructure automation
Experience managing security of Microsoft 365 and Google Workspace tenants
Certifications: OSCP, GCIH, GCFA, or equivalent

📌 Senior Security Engineer, 100% En remoto (España)
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