Senior Software Engineer, iOS (Contract)

The Wikimedia Foundation is a nonprofit organization that operates Wikipedia and other free knowledge projects. The Senior Software Engineer, iOS will join the App Growth team on a 3-month full-time contract to improve mobile Wikipedia experiences for a global, multilingual audience, leading medium-sized initiatives, system design, implementation, testing, observability, and cross-functional collaboration.

Responsibilities:

• Delivery and enablement - Delivery of medium complexity initiatives from technical discovery through delivery. Breaks down initiatives into features, drive estimation and manage scope. Identifies risks early, and helps the team make pragmatic tradeoffs across quality, velocity, maintainability, and user impact
• Implementation - Improving the mobile Wikipedia product experiences that serve a global, multilingual audience on iOS. Leads system design for medium-sized projects and can design and build accessible, adaptable, scalable components
• Quality, testing and observability - Consistently builds software that is easy to test, observe and debug. Instruments features that enable deeper analysis by Product Analysts
• Cross-functional collaboration - Partners with product managers, designers, analysts, and native app engineers to shape pragmatic solutions that balance user needs, technical constraints, platform expectations, and delivery timelines
• Prioritization - Proactively identifies high-impact technical opportunities and risks across the engagement timeframe, works with the team to clarify priorities and sequencing. Actively keeps the team aligned on outcomes, capacity, and shared goals
• Culture and standards - Complies with team standards in code review, technical design, testing, documentation, accessibility, observability, and decision-making - fostering transparency, empathy, and collaboration
• Operational Awareness - Plans work with awareness of downstream or upstream effects

Requirements:

• Bachelor's and 5-10+ years related professional experience with significant experience building iOS applications
• Strong professional experience and proficiency with Swift, SwiftUI, UIKit, and familiarity with architectural patterns in iOS
• Experience of iOS performance optimisation techniques to ensure smooth, responsive, and high-performing applications under a variety of conditions
• Experience working in a self-driven, lean environment
• Commitment to the Foundation's Mission and Values
• Experience adding webview-wrapped experiences to existing native mobile apps (iOS or Android)
• Experience in maintaining cross-platform mobile applications
• Experience building mobile games or other interactive mobile experiences
• Experience with data science, machine learning, and/or AI (e.g., familiarity with prompt engineering, Jupyter notebooks experience, etc.)
• Familiarity with Wikipedia / wikitext / markdown editing or content management systems (e.g., MediaWiki, Drupal, WordPress)
• Experience with leveraging agentic coding to scale the work of small engineering teams
• Bachelor's, master's, or doctorate degree in computer science, management information systems, or STEM field (or equivalent certification)
• Prior experience with MediaWiki or Wikimedia projects
• A history of open source contributions