Hello,
In 2018, the Wikibase Registry was started to create a Wikibase of Wikibases, linking the different Wikibases in existence together in pursuit of a greater “Wikibase federation."
The Registry was started as a standalone Wikibase on Wikimedia Cloud Services, and it had fallen behind in content and technical maintenance. Lack of effective anti-spam measures meant strict editing restrictions, which did not help.
Since then, a new Wikibase Cloud supported by Wikimedia Germany was created. Since this service will continue to receive software updates and generally has more features, I have migrated the contents of Wikibase Registry to a new wiki at a new URL: https://wikibase.world. I encourage you to sign up and, if you have a Wikibase accessible over the open internet, to add an entry for it.
Links to Wikibase Registry will continue to work indefinitely. As Wikibase World is a new wiki with new item and property identifiers, I have created a static mapping between old and new at https://wikibase-registry.wmflabs.org/mapping. This mapping forms the basis of the redirect service; try visiting https://wikibase-registry.wmflabs.org/wiki/Item:Q5 or https://wikibase-registry.wmflabs.org/entity/P19 to see it in action.
The old Wikibase Registry is available as a read-only archive at https://wikibase-registry-archive.wmcloud.org/wiki/Main_Page. It says on the site that it is going offline today, July 1, but so long as no vulnerabilities in the old version of MediaWiki being used are being exploited in its read-only state I can keep it online indefinitely[1]. However, once it goes offline, you should assume it will not return. However, be assured that final XML and RDF dumps were created and uploaded to the Internet Archive: https://archive.org/details/wikibase-registry-final-2023-06-16.
Finally, I have created a companion Discourse to go along, at https://forum.wikibase.world. This Discourse can also be used for other Wikibases that wish to have a place for discussion without setting up their own forum.
Thank you, James Hare
[1] The one hard deadline I can think of will be in mid-2025 when the operating system running the VM reaches end-of-life, at which point I will be forced to shut it down.