Collaboration logo V2.svg
Later this month, everyone will be able to use the same user name on every wiki, thanks to Single-User Login. As a result, cross-wiki collaboration and communication is expected to improve. Collaboration logo by Berdea, freely licensed under CC-BY-SA 3.0.

On March 16, 2001, two months after Wikipedia’s creation, Wikipedia co-founder Jimmy Wales announced and launched the first Wikipedia projects to be written in languages other than English, starting with the German and Catalan Wikipedias. The Wikimedia Foundation now hosts over 900 wikis in hundreds of languages, covering ten subject areas; this includes Meta-Wiki, the global community site, and, the website for development and documentation of the software that runs the Wikimedia wikis.


The rapid growth of the projects presented a problem early on — one that is finally being solved this month with Single-User Login: accounts created on one wiki used to only work on that wiki. If you wanted to edit a different wiki, you had to register a new account. Sometimes, and with growing frequency over the years, your account name was already registered by someone else on that different wiki. Lack of single-user login required you to register a different account name, splitting your identity across the wikis. This caused problems in software development, making it hard to develop global notifications or global watchlists, for example. The lack of persistent identity across the wikis also caused problems with users being mistaken for other users: users blocked on one wiki were sometimes assumed to be the same person on another, for instance. As of last month, there were 2.8 million accounts with conflicting, identical usernames, out of over 90 million local accounts.


As early as May 2004, while proposing Wikimedia Commons as a free media repository, Erik Moeller (User:Eloquence) put forward the idea of using Commons as a place to unify all usernames. In June of 2005 the first specifics were proposed to establish and use “global accounts.” The Wikimedia Foundation committed software architect and engineer Brion Vibber to work on that project. Due to various complications, the resulting global log-in system, CentralAuth, was not ready for general use until 2008 — and only in 2009 were new account name requests checked against those that registered their global name. Following a community request in 2012 to complete single-user login and make all accounts global, the Wikimedia Foundation provided more resources for that task. In the spring of 2013, James Forrester was tasked with unifying and globalizing all accounts, and early planning began. Dan Garry took over the project at the end of 2013, and throughout the summer of 2014 he led the engineering work to complete the task. I, Keegan Peterzell, took over the project once most engineering challenges had been met, at the end of October 2014.


The move to all-global accounts has been taking place in stages over the past eight months. In August 2014, we started migrating all local accounts that did not conflict with another local account or a global account, making them global across all wikis. In September 2014, the ability to rename accounts moved from local requests to a global group, to prevent local renames that would separate an account from its global owner. In November and December 2014, we tested new global rename processing tools. In January 2015, GlobalRenameRequest was deployed on all wikis, with the special queue where requests are sent for processing. This special page allows users to request a new name from the wiki on which they are logged in, using localized, translated text. The form is short and allows global renamers to smoothly process requests from all wikis. In February 2015, we focused on preventing the ability to create an account that conflicted with a global account by anyone, as well as contacting over 80,000 accounts with unconfirmed email addresses to request confirmation. In March 2015, a script was run over all the remaining clashing accounts, based on a rename selection scheme to determine the final global accounts and which other accounts needed to be renamed.

Final stages

On March 17, 2015, we started contacting the 2.8 million accounts being renamed. Since being contacted, over 1.34 million accounts have been connected to their global accounts and will no longer need to be renamed; and over 10,000 accounts have been renamed to a new global account name of their choosing. This week, we will begin the process of renaming the remaining 1.46 million accounts – those which have not responded to all attempts at outreach. That process is expected to take approximately one to two weeks. Once renamed, account owners will still be able to log in using their old credentials and will be shown information about the renaming. At any point after being renamed, all affected accounts are free to request a new name of their choice, using GlobalRenameRequest. To learn more, visit this help page.

Once finalization is complete, every account on Wikimedia projects will be unique in all projects. Any confusion about user identities will be addressed by setting up a global user page for your account in the unified world; and software developers will be able to start projects that had been put on hold for over a decade due to this ongoing issue.

As a result of Single-User Login, cross-wiki collaboration and communication should improve, which should help the health of the overall Wikimedia movement. I look forward to sharing this new, unified wiki experience with the rest of you. The wait and the work should all be well worth it.

Keegan Peterzell
Community Liaison
Wikimedia Foundation