The “WikiWay” is the open editing philosophy of wikis meant to foster open collaboration and continuous improvement of their content. Just like other online communities, wikis often introduce and enforce conventions, constraints, and rules for their content, but do so in a considerably softer way, expecting authors to deliver content that satisfies the conventions and the constraints, or, failing that, having volunteers of the community, the WikiGnomes, fix others' content accordingly. Constrained wikis is our generic framework for wikis to implement validators of community-specific constraints and conventions that preserve the WikiWay and their open collaboration features. To this end, specific requirements need to be observed by validators and a specific software architecture can be used for their implementation, that is, as independent functions (implemented as internal modules or external services) used in a nonintrusive way. Two separate proof-of-concept validators have been implemented for MediaWiki and MoinMoin, respectively, providing an annotated view functions, that is, presenting content authors with violation warnings, rather than preventing them from saving a noncompliant text. 1. Introduction Since their first apparition more than 15 years ago, wikis have gained wide acceptance and now convey a nonnegligible share of the whole content delivered via the web. Wikipedia alone suffices to showcase what we would be missing without wikis: Wikipedia is among the top 10 most visited websites, (Alexa ranking, http://www.alexa.com/topsites/, retrieved 07/02/2010) is the most popular general reference work on the web  and delivers about 12 millions of articles. All this would probably not have been possible with “traditional”, prewiki webauthoring. The peculiar innovation brought by wikis is what has been termed “the WikiWay”: an open editing philosophy that allows users to easily collaborate on web content, imposing as few restrictions as possible on content authors . That in turn fosters the creation of possibly immensely large, as in the case of Wikipedia, communities which author contents collaboratively. In a sense, a wiki can be considered a state-of-mind, an inclination shared by the users, rather than a collection of scripts and pages. Technically, the WikiWay is incarnated by careful technological choices which reduce content contribution barriers. Let us briefly review such choices. Direct Editing within Browsers To relax the software and infrastructure requirements which are needed to contribute content on the web, for example,
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