Senior Software Engineer

Summary

The Wikimedia Foundation is looking for a Senior Software Engineer to join the MediaWiki Interfaces team. MediaWiki is the open-source platform that powers Wikipedia and its sister projects - impacting hundreds of millions of Wikipedia users across the globe. Our team owns the web API and other integration interfaces of MediaWiki, enabling other teams to create features that allows users to access, edit, and consume knowledge efficiently and reliably. The MediaWiki Product Insights have more information on the kind of work the group undertakes.

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-7 time zones to accommodate members of your team around the world.

You will be responsible for:

• 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;
• Collaborating with the Product team and the community to ensure technical solutions align with user and contributor needs;
• Coaching and mentoring teammates to support continuous growth and confidence in both technical and interpersonal skills.

Qualities we are looking for:

• 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;
• Collaborative leadership: You inspire trust and progress through support, example, and thoughtful contributions.

Requirements:

• Commitment to the Foundation's Mission and Values;
• 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;

Additionally, we’d love it if you have:

• • Experience developing frameworks (designing for reuse, extensibility, stability, and backward compatibility);
  • Experience defining and working with SLAs/SLOs or other production reliability frameworks;
  • Prior experience with MediaWiki or Wikimedia projects;
  • Contributions to open-source software;
  • Experience with developer experience tooling, public APIs, or platform teams;
  • Experience working in a remote, distributed team.

The Wikimedia Foundation is the nonprofit organization that operates Wikipedia and the other Wikimedia free knowledge projects. Our vision is a world in which every single human can freely share in the sum of all knowledge. We believe that everyone has the potential to contribute something to our shared knowledge, and that everyone should be able to access that knowledge freely. We host Wikipedia and the Wikimedia projects, build software experiences for reading, contributing, and sharing Wikimedia content, support the volunteer communities and partners who make Wikimedia possible, and advocate for policies that enable Wikimedia and free knowledge to thrive. 

The Wikimedia Foundation is a charitable, not-for-profit organization that relies on donations. We receive donations from millions of individuals around the world, with an average donation of about $15. We also receive donations through institutional grants and gifts. The Wikimedia Foundation is a United States 501(c)(3) tax-exempt organization with offices in San Francisco, California, USA.

As an equal opportunity employer, the Wikimedia Foundation values having a diverse workforce and continuously strives to maintain an inclusive and equitable workplace. We encourage people with a diverse range of backgrounds to apply. We do not discriminate against any person based upon their race, traits historically associated with race, religion, color, national origin, sex, pregnancy or related medical conditions, parental status, sexual orientation, gender identity, gender expression, age, status as a protected veteran, status as an individual with a disability, genetic information, or any other legally protected characteristics.

The Wikimedia Foundation is a remote-first organization with staff members including contractors based 40+ countries*. Salaries at the Wikimedia Foundation are set in a way that is competitive, equitable, and consistent with our values and culture. The anticipated annual pay range of this position for applicants based within the United States is US$[109,047] to US$[169,455] with multiple individualized factors, including cost of living in the location, being the determinants of the offered pay. For applicants located outside of the US, the pay range will be adjusted to the country of hire. We neither ask for nor take into consideration the salary history of applicants. The compensation for a successful applicant will be based on their skills, experience and location. 

*Please note that we are currently able to hire in the following countries: Australia, Austria, Bangladesh, Belgium, Brazil, Canada, Colombia, Costa Rica, Croatia, Czech Republic, Denmark, Egypt, Estonia, Finland, France, Germany, Ghana, Greece, India, Indonesia, Ireland, Israel, Italy, Kenya, Mexico, Netherlands, Nigeria, Peru, Poland, Singapore, South Africa, Spain, Sweden, Switzerland, Uganda, United Kingdom, United States of America and Uruguay.  Our non-US employees are hired through a local third party Employer of Record (EOR). 

We periodically review this list to streamline to ensure alignment with our hiring requirements. 

All applicants can reach out to their recruiter to understand more about the specific pay range for their location during the interview process.

If you are a qualified applicant requiring assistance or an accommodation to complete any step of the application process due to a disability, you may contact us at [email protected] or +1 (415) 839-6885.

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