The Wikimedia Foundation is seeking a Senior Software Engineer to enhance the MediaWiki Interfaces team. This role aims to improve the web API and integration interfaces of MediaWiki, the platform powering Wikipedia, to enable efficient and reliable access, editing, and consumption of knowledge for hundreds of millions of users globally. The position focuses on combining technical expertise with mission-driven impact, emphasizing code quality, leadership, data-driven decision-making, and fostering a culture of continuous improvement.
Requirements
- Extensive experience in software engineering, ideally in high-impact web platforms and/or open-source
- Good understanding of HTTP
- Proficiency in PHP and JavaScript
- 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
Responsibilities
- Designing, developing, 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
- Contributing to the adoption and advocacy of API-first development, and influencing best practices in system design, SLOs/SLAs, and OpenAPI Specification
- Championing product metrics: ensuring that key user journeys are instrumented and monitored to guide decisions and 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
Other
- Commitment to the Foundation's Mission and Values
- Clear communicator: You explain complex ideas simply and foster shared understanding across engineering, product, and non-technical audiences
- Outcome-oriented: You prioritize work that delivers value to users and aligns with organizational goals. You balance ideal solutions with the constraints of scale, legacy, and user expectations
- Accountable: You own your work end-to-end and help establish a culture of responsibility and follow-through
- Candid and respectful: You offer feedback directly, constructively, and with care - and invite the same in return. You support growth by challenging ideas, not people
