In T253624 we looked at if we wanted to continue maintaining our own set of codesniffer sniffers and decided not to.
In T164653 we reviewed the rules that were in wikibase-codesniffer and moved many of them to mediawiki codesniffer.
Per T253624#6373219 the rules that needed to be moved in order to no longer need wikibase-codesniffer have been merged.
Now that v33 has been released, we should be able to remove wikibase-codesniffer entirely and retire the project (using rules with a slightly modified name)
The overhead that this will reduce is discussed slightly in T253624#6165346
>>! In T266823#6589625, @thiemowmde wrote:
> My suggestion for this migration would be to copy-paste the entire file https://github.com/wmde/WikibaseCodeSniffer/blob/master/Wikibase/ruleset.xml to every codebase that currently uses the WikibaseCodeSniffer, and slowly simplify it, e.g. remove exclusions you don't want to exclude any more, as well as remove additions you don't care about. I suggest to keep the comments, as they help other developers to understand that some exclusions are very intentional, and the Wikidata team doesn't want anybody to re-enable them (if this is still the case). Note that excluding a sniff is not a bad thing, and doesn't mean the code is bad. At this point we have sooo many sniffs, and many of them are about teeny tiny details nobody would really argue about. Feel free to diverge from the MediaWiki rule set a bit if it makes your team feel more comfortable.
 The same rules are applied on all repositories that currently use wikibase-codesniffer after the change
 All WMDE repos that use wikibase-codesniffer no longer use wikibase-codesniffer
 The wikibase-codesniffer project is appropriately discontinued (on git, in README, in packagist etc)