Mozilla
SeniorSiteReliabilityEngineer
Neural analysis suggests this role is
optimal for Senior candidates.
“Senior Site Reliability Engineer at Mozilla. Skills: Site Reliability Engineering, Kubernetes, Infrastructure as Code, CI/CD. Operate EKS-based Kubernetes platform. Support service migrations”
Industry & Context.
Troubleshooting; Root-cause analysis
On-call rotation, Overlap with Pacific Time zone
What They're Looking For.
Must Have
7+ years of experience in infrastructure, platform engineering, or site reliability roles, Hands-on production Kubernetes experience, Infrastructure-as-code on AWS using Terraform, OpenTofu, or Pulumi, Security awareness in day-to-day infrastructure work, Demonstrated ownership mindset, Excellent async written communication, Ability to collaborate effectively with software engineers and non-engineering stakeholders, Ability to learn, evaluate, and responsibly use emerging technologies
Nice to Have
Experience with GitOps workflows, Familiarity with Keycloak or similar identity platforms, Knowledge of email protocols, Experience operating email infrastructure, Prior work in or alongside an open-source community, French, German, Japanese, or other language proficiency
What You'll Do.
Operate EKS-based Kubernetes platform
Support service migrations
Improve platform reliability
Develop CI/CD systems
Support release workflows
Diagnose production incidents
Debug production incidents
Implement improvements
Enhance system reliability
Write infrastructure in Pulumi
Maintain infrastructure in Pulumi
Write infrastructure in Terraform
Maintain infrastructure in Terraform
Write infrastructure in OpenTofu
Maintain infrastructure in OpenTofu
Operate observability stack
Evolve observability stack
Partner with engineering teams
Incorporate instrumentation
Incorporate monitoring
Apply security-conscious infrastructure practices
Diagnose production issues
Debug production issues
Drive root-cause analysis
Implement post-incident improvements
Prevent recurring problems
Participate in on-call rotation
Collaborate with SDEs
Collaborate with SREs
Support service onboarding
Contribute to runbooks
Contribute to architecture documentation
Contribute to team processes
How You'll Work.
Team & Collaboration
Software Development Engineers; Team members; Community contributors; Geographically distributed team; Engineering teams; Non-engineering stakeholders
Communication Scope
Written communication
Full Job Description
Why Thunderbird? Thunderbird is one of the world’s most trusted open-source email applications, empowering more than 20 million people globally. At MZLA, the team behind Thunderbird, we build privacy-respecting communication tools that help people manage their digital lives while staying in control of their data. We are open source by design. Our products are developed transparently and in collaboration with a global community of contributors, and that same spirit shapes how we work: collaboratively, inclusively, and with a shared commitment to putting users first. Our small but growing distributed team includes 65+ people across seven countries. As Thunderbird evolves beyond a single desktop application, we are expanding across desktop, mobile, and paid services to build independent, privacy-respecting alternatives to big tech ecosystems. Our revenue model combines user donations, which help keep Thunderbird’s apps freely available, with paid services that cover the costs of hosted offerings while supporting long-term sustainability and continued innovation. A note about MZLA and Mozilla: MZLA Technologies Corporation is the nonprofit-owned company behind Thunderbird and part of the Mozilla family. MZLA is separate from Mozilla Corporation and has its own compensation programs, benefits, and employment policies. To learn more, visit www.thunderbird.net The opportunity The Senior Site Reliability Engineer establishes and maintains the infrastructure and operational systems that Thunderbird users and teams depend on every day. You'll design and develop CI/CD systems for MZLA websites, services, and release workflows, diagnose and debug production incidents, and implement improvements to enhance system reliability. We believe that good infrastructure work is invisible when it's going well and invaluable when it isn' t. This role is for someone who treats production as something to be understood, not just kept running. You write things down, flag problems before they b
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