Senior Software Engineer, MediaWiki

Job Posting Organization:
The Wikimedia Foundation is a nonprofit organization that operates Wikipedia and other Wikimedia free knowledge projects. Established with the vision of a world where every individual can freely share in the sum of all knowledge, the foundation believes in the potential of every person to contribute to shared knowledge and the importance of free access to that knowledge. The organization hosts Wikipedia and various Wikimedia projects, builds software experiences for reading, contributing, and sharing content, supports volunteer communities, and advocates for policies that enable Wikimedia and free knowledge to thrive. As a charitable, not-for-profit organization, it relies on donations from millions of individuals globally, with an average donation of about $1

• The Wikimedia Foundation is a United States 501(c)(3) tax-exempt organization with offices in San Francisco, California, USA. It values diversity and strives to maintain an inclusive workplace, encouraging applicants from diverse backgrounds to apply. The foundation operates with staff members, including contractors, in over 40 countries, ensuring a global reach and impact.

Job Overview:
The Senior Software Engineer position within the MediaWiki Platform team offers a unique opportunity to engage in impactful work while leveraging technical expertise. The MediaWiki platform is the backbone of Wikipedia and its sister projects, serving hundreds of millions of users worldwide. The MediaWiki Platform team is responsible for building and maintaining the core of MediaWiki, focusing on components such as authentication, notifications, and media management. The team's mission is to provide a robust foundation for feature teams, emphasizing performance, reliability, and scalability to ensure equitable access to free knowledge. In this role, the Senior Engineer will not only write high-quality code but also lead by example, prioritize impactful work, and support decision-making through metrics and observability. The position requires collaboration with various teams and community members to align technical solutions with organizational strategies and user needs, fostering a culture of accountability, transparency, and continuous improvement.

Duties and Responsibilities:
The Senior Software Engineer will be responsible for designing, improving, and maintaining key components of the MediaWiki stack. This includes driving technical quality and operational excellence by defining and reinforcing standards in testing, observability, and system reliability. The engineer will autonomously create proofs of concept, write design documents, and break down complex projects into actionable tasks to support less experienced team members. Additionally, the role involves developing and improving shared capabilities such as authentication, caching, and rate limiting to enable other teams to build efficiently. The engineer will champion key product metrics by focusing on measurable outcomes that guide decisions and evaluate success. Leading by example in code review, decision-making, and team culture is essential, as is improving and automating processes for identifying, tracking, and resolving production issues. Collaboration with the Product team and the community is crucial to ensure that technical solutions align with the Wikimedia Foundation's strategy and the needs of feature teams and volunteer contributors. Coaching and mentoring teammates to support their growth in both technical and interpersonal skills is also a key responsibility.

Required Qualifications:
Candidates must demonstrate a commitment to the Wikimedia Foundation's mission and values. Extensive experience in backend software engineering is required, along with familiarity with platform or infrastructure products that serve internal or external engineering teams. A strong background in databases and event streams, including schema design, query optimization, and efficient data access patterns, is essential. Candidates should possess a deep understanding of software architecture, testing methodologies, and system design. Strong experience in observability practices, including setting up metrics, logging, monitoring, and alerting, is also necessary. Familiarity with incident response, root cause analysis, and follow-up processes is expected, as well as experience working with CI/CD pipelines and automated test infrastructure.

Educational Background:
While the job description does not specify exact educational requirements, it is generally expected that candidates possess a degree in Computer Science, Software Engineering, or a related field. Advanced degrees may be preferred but are not explicitly required. The emphasis is on practical experience and demonstrated skills in software engineering rather than formal educational credentials alone.

Experience:
The position requires extensive experience in backend software engineering, with a strong emphasis on practical application and problem-solving skills. Candidates should have a proven track record of working on complex software projects and be comfortable with both independent and collaborative work environments. Experience in developing frameworks, working with CI/CD pipelines, and contributing to open-source software is highly valued. Familiarity with remote work dynamics and experience in distributed teams will be advantageous.

Languages:
While the job description does not specify mandatory languages, proficiency in English is essential for effective communication within the team and with stakeholders. Additional language skills may be beneficial, particularly in languages relevant to the Wikimedia Foundation's global audience and contributor base, but are not explicitly required.

Additional Notes:
This is a fully remote position, allowing for flexibility in work location. However, candidates must be able to work hours that overlap with UTC-2 to UTC+3 time zones to accommodate team members worldwide. The Wikimedia Foundation offers competitive and equitable salaries, with the anticipated annual pay range for applicants within the United States being US$113,082 to US$175,725, depending on various factors including location and experience. For applicants outside the US, the pay range will be adjusted according to the country of hire. The foundation does not consider salary history in its compensation decisions, focusing instead on the skills and experience of the applicant. The organization is committed to maintaining an inclusive and equitable workplace, encouraging diverse applicants to apply.