Senior Security Engineer, 100% En Remoto

Senior Security EngineerMattermost is the leading collaborative workflow platform for defense, intelligence, security, and critical infrastructure.Trusted by the U.S. 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.Why Join MattermostFully remote, globally distributed team no commute, genuine flexibilityBe a key voice in shaping and delivering security strategyCompetitive salary, equity, and benefits with meaningful work attachedThe RoleAs 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.You will work across a globally distributed team and partner closely with Engineering to manage AI-enabled risk.Key ResponsibilitiesLead security and IT projects to enhance the security posture of infrastructure and the companyDetect, investigate, and remediate security incidents using SIEM, EDR, and SOAR tooling (e.g. CrowdStrike, SentinelOne)Conduct threat hunting across cloud and endpoint environments using a Zero Trust frameworkAdminister company-wide IAM and security monitoring infrastructureContribute to security policies, incident response, forensics, and endpoint management programmesPartner with Engineering to assess and mitigate risks from AI-enabled tools and workflowsExplore and implement AI/automation in detection, analysis, and response pipelinesEngage closely with North American and international staff across time zonesRequired Background SkillsBachelor s degree in Computer Science or a related field, or significant professional security experience3+ years of hands-on experience in security engineering and incident responseExperience with SIEM platforms and security monitoring systemsExperience with EDR tools such as CrowdStrike or SentinelOneKnowledge of SOAR platforms and automation of security workflowsFamiliarity with Zero Trust architecture principles and threat hunting methodologiesExperience with cloud security controls across AWS, GCP, and/or AzureStrong knowledge of Linux systems and Kubernetes/Docker environmentsExperience with IAM solutions and infrastructure automationPractical experience evaluating security implications of AI systems and AI-assisted workflowsExperience managing security of Microsoft 365 and Google Workspace tenantsExcellent written and verbal communication skillsPreferred Background SkillsExperience with certification processes: SOC2, ISO **, FedRAMP, or Cyber Essentials PlusCertifications: OSCP, GCIH, GCFA, or equivalent penetration testing / incident response credentialsExperience in Go or PythonBackground in open-source communitiesEndpoint security management experience in a fully remote organisationExport Control EligibilityThis role may involve access to information subject to U.S. export control regulations (EAR/ITAR).Applicants should be aware that eligibility requirements may apply.Many Spain-based security professionals with defence backgrounds will qualify.Mattermost takes a market-based approach to pay and pay may vary depending on your location.The successful candidate s starting pay will be determined based on job-related skills, experience, qualifications, work location, and market conditions.These ranges may be modified in the future.Posting Range**** EURMattermost is an EEO Employer, we are a remote-first, open-source company.We are continually working to expand our hiring in more countries and regions, ensuring compliance with local laws and regulations, which takes time.Mattermost values your unique perspective we welcome all applicants.We encourage individuals from all backgrounds to apply and are committed to assessing candidates based on their skills and qualifications.If you require accommodations during the interview process, please let us know we re happy to assist.SIEM, EDR, SOAR, CrowdStrike, SentinelOne, Zero Trust

Bachelor s degree in Computer Science or a related field, or significant professional security experience 3+ years of hands-on experience in security engineering and incident response Experience with SIEM platforms and security monitoring systems Experience with EDR tools such as CrowdStrike or SentinelOne Knowledge of SOAR platforms and automation of security workflows Familiarity with Zero Trust architecture principles and threat hunting methodologies 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 Practical experience evaluating security implications of AI systems and AI-assisted workflows Experience managing security of Microsoft 365 and Google Workspace tenants Excellent written and verbal communication skills Preferred Background Skills Experience with certification processes: SOC2, ISO *****, FedRAMP, or Cyber Essentials Plus Certifications: OSCP, GCIH, GCFA, or equivalent penetration testing / incident response credentials Experience in Go or Python Background in open-source communities Endpoint security management experience in a fully remote organisation

The successful candidate s starting pay will be determined based on job-related skills, experience, qualifications, work location, and market conditions. These ranges may be modified in the future. Posting Range ***** EUR Mattermost is an EEO Employer, we are a remote-first, open-source company. We are continually working to expand our hiring in more countries and regions, ensuring compliance with local laws and regulations, which takes time. Mattermost values your unique perspective we welcome all applicants. We encourage individuals from all backgrounds to apply and are committed to assessing candidates based on their skills and qualifications. If you require accommodations during the interview process, please let us know we re happy to assist. SIEM, EDR, SOAR, CrowdStrike, SentinelOne, Zero Trust

Senior Security Engineer Mattermost is the leading collaborative workflow platform for defense, intelligence, security, and critical infrastructure. Trusted by the U.S. 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.