Mozilla
SeniorSiteReliabilityEngineer
Neural analysis suggests this role is
optimal for Senior candidates.
“Senior Site Reliability Engineer at Mozilla. Skills: Site Reliability Engineering, Kubernetes, CI/CD, Infrastructure as Code. Operate EKS-based Kubernetes platform. Evolve EKS-based Kubernetes platform”
Industry & Context.
Troubleshooting; Root-cause analysis
On-call rotation, Overlap with Pacific Time
What They're Looking For.
Must Have
7+ years infrastructure experience, 7+ years platform engineering experience, 7+ years site reliability experience, Hands-on production Kubernetes experience, Workload operations experience, Troubleshooting experience, Cluster management experience, Infrastructure-as-code on AWS experience, Security awareness in infrastructure work, Ownership mindset, Ability to proactively identify issues, Ability to drive work to completion, Ability to communicate risks early, Excellent async written communication, Ability to collaborate effectively, Ability to learn emerging technologies, Ability to evaluate emerging technologies, Ability to responsibly use emerging technologies, Availability for regular overlap hours
Nice to Have
GitOps workflows experience, Keycloak familiarity, OIDC familiarity, SAML familiarity, Federation familiarity, Email protocols knowledge, Email infrastructure operating experience, Open-source community work experience, French language proficiency, German language proficiency, Japanese language proficiency, Other language proficiency
What You'll Do.
Operate EKS-based Kubernetes platform
Evolve EKS-based Kubernetes platform
Support service migrations
Support platform improvements
Support reliability initiatives
Develop CI/CD systems
Support website releases
Support service releases
Support desktop releases
Contribute to pipeline reliability
Contribute to OIDC authentication
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 into design
Incorporate monitoring into design
Apply security-conscious practices
Implement least-privilege IAM
Implement secrets management
Implement network segmentation
Diagnose production incidents
Debug production incidents
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
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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