Enhanced Search for Wikibase

Recently, we at Professional Wiki released Wikibase Faceted Search, a new Wikibase extension that enhances the default search page experience with user-friendly filtering capabilities.

This blog post delves into the details of what the extension can do and tells the story of how it came to be.

Wikibase Faceted Search

Wikibase Faceted Search enhances MediaWiki’s search with faceted search capabilities. When searching for items, you can filter the results by the values of their statements using the right sidebar.

The sidebar displays the most common values for each property, together with the number of items that have that value. Each facet of the search appears in a collapsible element on the sidebar. You can build complex queries by selecting multiple values for the same property or different properties, including range queries, conjunctions (AND), and disjunctions (OR). 

MaRDI and Wikibase

Scientists thrive on curiosity and a drive to understand details precisely. That mindset translates into demanding requirements for data-management tools. In Germany, the National Research Data Infrastructure (NFDI) treats research data as a public good and aims to make it ffindable, accessible, interoperable, and reusable (FAIR). Rather than building a single central platform, Germany funds discipline-specific consortia to create infrastructure tailored to their respective fields.

The Mathematical Research Data Initiative (MaRDI) believes that the goals of NFDI align naturally with the Wikimedia movement. In 2021, MaRDI adopted Wikibase as the backbone of its mathematical research database. They have since heavily customized and extended their Wikibase, commissioning new Wikibase extensions as needed and improving the upstream software.

User testing and search

During usability tests, MaRDI researchers found that the default search interface used on Wikimedia projects did not fit their workflows. Users rarely searched for page text; instead, they wanted to filter results by property values, as is common in other research-data portals. For example, they might want to find Wikibase items about publications published after 2020 with a specific author.

Development of Wikibase Faceted Search

The MaRDI team commissioned us for Wikibase software development following prior successful collaborations, such as the development of the SPARQL extension.

We completed the first usable version of Wikibase Faceted Search after approximately two months of development, with further enhancements made over the next two months. We did the software development work, which included product management, UI design, and testing; the MaRDI team provided the initial concept and rigorous feedback.

Initially, we planned to build on top of WikibaseCirrusSearch, an existing extension that makes Wikibase values available via Elasticsearch. During the project, we discovered that due to limitations in WikibaseCirrusSearch, we had to create a new and more capable indexing strategy from scratch. This was the biggest surprise and challenge we had to overcome, and it took quite some time to implement well. But the work paid off — Wikibase Faceted Search can now serve as a replacement for WikibaseCirrusSearch and enables novel structured queries, even for those not using the faceted search UI.

For more technically minded readers: the search index that Wikibase Faceted Search creates allows for efficient aggregation queries (required by list facets) and supports combining Wikibase statement values with regular wikitext in the same search document.

Development happens on the Wikibase Faceted Search GitHub,  where you can post feature requests, bug reports, and software contributions.

Results, impact, and next steps

We released the first official version of Wikibase Faceted Search in 2025, together with usage documentation, installation instructions, and a demo video.

The new extension fills the need identified by MaRDI’s user testing. It offers the kind of intuitive, filter-driven discovery scientists expect, it’s easy to configure, and it can be reused by any Wikibase operator with similar structured-data needs.

You can see Wikibase Faceted Search in action on the MaRDI Portal search page.

Because the new extension is fully open source, you can install it on your own Wikibase for free. Wikibase Faceted Search is not yet available as part of Wikibase Suite as of the this post’s publication date. We hope it will soon be added, as has happened with some similarly developed Wikibase extensions, such as Wikibase EDTF and Wikibase Local Media.

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About the authors

Jeroen De Dauw is the founder and CEO of Professional Wiki. As a software architect and one of the original developers of Wikibase, he leads MediaWiki and Wikibase projects, providing both technical and product expertise. Besides having helped dozens of large organizations and enterprises with their knowledge management needs, Jeroen is a prolific open-source contributor, known for developing high-quality, user-centric software.

Moritz Schubotz is a Senior Researcher at FIZ Karlsruhe ‒ Leibniz-Institute for Information Infrastructure. He is co-spokesperson of the MaRDI project (Germany’s mathematical research data initiative), represents Wikimedia in the W3C Math Working Group, founded the Wikimedia Community Group Math, and has maintained the Math extension since 2012.

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Acknowledgments

This research was supported by the mathematical research data initiative MaRDI, funded by the Deutsche Forschungsgemeinschaft (DFG), project number 460135501, NFDI 29/1 “MaRDI – Mathematische Forschungsdateninitiative”.

Header image: Binoculars at Duomo roof, Milan by Alberto P Veiga (CC BY-NC-SA 2.0)