Senior Software Engineer, MediaWiki
Summary
The Wikimedia Foundation is looking for a Senior Software Engineer to join the MediaWiki Platform team. MediaWiki is the open-source platform that powers Wikipedia and its sister projects - impacting hundreds of millions of Wikipedia users across the globe.
The MediaWiki Platform team builds and maintains the core of MediaWiki as well as the components responsible for authentication, notifications, and media management. The team’s mission is to provide a solid foundation for feature teams to build on. It focuses on performance, reliability and scalability, helping to ensure broad and equitable access to free knowledge.
This role offers a unique opportunity to combine technical depth with mission-driven impact. As a Senior Engineer, you will not only write robust code but also lead by example, prioritize high-impact work, support better decision-making through metrics and observability and foster a culture of accountability, transparency, and continuous improvement.
Important: We are a fully remote team.



Your working hours will need to overlap with UTC-2 to UTC+3 time zones to accommodate members of your team around the world.
You will be responsible for:
- 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,

📌 Senior Software Engineer (España)
🏢 Wikimedia Foundation
📍 España