Semantic MediaWiki (SMW) is an advanced version of the MediaWiki software that allows for better management of data than the regular counterpart. It was touted as the key selling point of Yaron Koren's now-dormant Referata network (on which this site's founder was an administrator and ran four separate wikis). On semantic sites, users can store, organise and edit items with features such as properties, types and forms. Data can even be queried, thanks to the "Special:Ask" function.
SMW was occasionally proposed for installation on Miraheze throughout the late 2010s, but was turned down each time due to Referata already offering it (before 2020–2021), infrastructure/performance concerns, and in June 2021, incompatibility with MediaWiki 1.36. Although Koren's Cargo has been widely suggested in its place, the Constant Noble site instead adopted DynamicPageList3 as the closest perceived substitute to SMW in early July 2021.
On January 27, 2022, Miraheze's test site Betaheze launched a subdomain for SMW experimentation, a while after the 4.0.x era of Semantic MediaWiki was inaugurated. (MediaWiki on Miraheze is currently on version 1.38.4 (a542c27).) After a delay of several months, SMW was deployed on Miraheze on April 18, albeit marked as "ManageWiki restricted". Wikis wishing to use the extension must apply a request at Miraheze Meta's Stewards' noticeboard.
At this writing, Semantic MediaWiki on Miraheze is "Permanently "experimental" and may be removed with little to no prior notice. WARNING: Disabling this extension after it's already been enabled will clear all SemanticMediaWiki database tables as well." It has so far been enabled as such on:
- the Conworlds Wiki (April 19, 2021)
- Rule the Seas (RTS) Wiki (May 2)
- this site (May 14)
- Feign Game Wiki (Turkish) (May 21–October 3)
- AliceSoft Wiki (June 4)
- Aral Gho (French; private) (July 11)
- RosettaCode.org (migrated version) (August 24)
- Art Mechanicum (August 25)