About this role
Job title: Senior Software Engineer, MediaWiki
About the Role The Wikimedia Foundation is looking for a Senior Software Engineer to join the MediaWiki Platform team. This role focuses on the core MediaWiki stack and components such as authentication, caching, and media management, delivering a solid foundation for feature teams while prioritizing performance, reliability, and scale. This is a fully remote role offering a chance to combine technical depth with mission-driven impact, with working hours overlapping UTC-2 to UTC+3 to collaborate with a distributed team.
What You'll Do
- Designing, improving, and maintaining key parts of the MediaWiki stack
- Driving technical quality and operational excellence by defining and reinforcing standards in testing, observability, and system reliability
- Comfortably and autonomously creating proofs of concept, writing design documents, and breaking down complex projects into actionable tasks to support less experienced team members
- Developing and improving shared capabilities (e.g., authentication, caching, rate limiting) that enable other teams to build efficiently and consistently
- Championing key product metrics by focusing on measurable outcomes that guide our decisions and help us to evaluate success
- Leading by example in code review, decision-making, and team culture - fostering transparency, empathy, and collaboration
- Improving and automating processes for identifying, tracking, and resolving production issues
- Collaborating with the Product team and the community to ensure technical solutions align with WMF strategy, feature teams and volunteer contributor needs
- Coaching and mentoring teammates to support continuous growth and confidence in both technical and interpersonal skills
What We're Looking For
- Commitment to the Foundation's Mission and Values
- Extensive experience in backend software engineering
- Familiarity with platform or infrastructure products that serve internal or external engineering teams
- Experience with databases and event streams, including schema design, query optimization, and efficient data access patterns
- Deep understanding of software architecture, testing methodologies, and system design
- Strong experience in observability practices: setting up metrics, logging, monitoring, and alerting
- Familiarity with incident response, root cause analysis, and follow-up processes
- Experience working with CI/CD pipelines and automated test infrastructure
- Clear communicator; Outcome-oriented; Accountable; Candid and respectful; Collaborative leadership
Nice to Have
- Experience developing frameworks (designing for reuse, extensibility, stability, and backward compatibility)
- Proficiency in PHP and JavaScript
- Familiarity with identity management, including OAuth
- Experience with Kubernetes ecosystem, including Envoy
- Experience with Prometheus and Grafana
- Experience defining SLAs/SLOs or other production reliability frameworks
- Prior experience with MediaWiki or Wikimedia projects
- Contributions to open-source software
- Experience working in a fully remote, distributed team