Wikimedia Foundation · 1 hour ago
Wikidata Platform Backend Migration Specialist (Contract Position)
United States
Contract
Remote
Mid LevelThe Wikimedia Foundation is seeking a contract Backend Migration Specialist to join the team supporting the Wikidata Platform. This role involves assisting with the migration of the Wikidata Query Service to a new system, identifying impacted queries, and supporting the community during the transition.
Computer Software
Responsibilities
Review existing WDQS example queries and determine which rely on Blazegraph-specific extensions or non-SPARQL-1.1 behavior
Help identify classes of non-standard queries (e.g., named subqueries, named paths, geospatial queries, MediaWiki API access)
Inform prioritization decisions by conducting heuristic-based analysis to estimate the volume and types of affected queries (e.g., replaying Blazegraph queries against the new backend and comparing failures or result differences)
Surface recurring pain points or missing abstractions back to the platform team
Collaborate with WMF and WMDE staff on tooling or analysis approaches, where appropriate
Rewrite example queries shown in the WDQS UI and documentation to be compatible with the new backend
Develop and document canonical rewrite patterns for common Blazegraph-specific query constructs
Identify inconsistencies in backward compatibility, and work with our teams to document alternative approaches or data access methods
Community support via documented responses, office hours, and guidance in rewriting queries
Update user-facing and technical documentation to reflect the new backend, ensuring accuracy, clarity, and usefulness during and after the migration. Examples of documentation to update include:
Wikidata Query Service help and tutorial pages
WDQS user manuals and technical/implementation documentation
Best-practice guidance for writing performant, standards-compliant SPARQL 1.1 queries
Qualification
Required
Strong, hands-on experience with SPARQL, including SPARQL 1.1
Experience working with large or complex RDF datasets
Experience with data platform migrations or deprecating legacy APIs
Ability to understand and refactor real-world queries written by others
Comfort working with incomplete information and evolving technical decisions
Strong written communication skills, especially for technical documentation
Ability to work independently while coordinating with multiple stakeholders
Preferred
Familiarity with Wikidata, WDQS, or MediaWiki-adjacent tooling
Experience supporting developer or researcher communities
Experience designing heuristics or lightweight analysis for query usage patterns
Company
Wikimedia Foundation
Wikimedia Foundation encourages the development and distribution of free educational content with projects such as Wikipedia.
Founded in 2003
501-1000 employees
H1B Sponsorship
Wikimedia Foundation has a track record of offering H1B sponsorships. Please note that this does not
guarantee sponsorship for this specific role. Below presents additional info for your
reference. (Data Powered by US Department of Labor)
Distribution of Different Job Fields Receiving Sponsorship
Represents job field similar to this job
Trends of Total Sponsorships
2025 (1)
2024 (4)
2023 (5)
2022 (3)
2021 (1)
2020 (5)
Funding
Current Stage
Late StageTotal Funding
$158.98MKey Investors
Alfred P. Sloan FoundationCraig Newmark PhilanthropiesGoogle.org
2020-01-01Grant· $2.1M
2019-09-10Grant· $2.5M
2019-01-22Grant· $1.1M
Leadership Team
Maryana Iskander
Chief Executive Officer
Denny Vrandečić
Head of Special Projects
Recent News
2026-01-19
2026-01-17
2026-01-17
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