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Promotion of rules from sandbox to rules/core/ is discussed in RulesProjPromotion.
(Update: bug 5123 gets rid of rules/core – now that is simply part of the old "rules" directory to keep things simpler.)
Extras/
We'll want to discuss the structure and process behind creating new extras directories further once we reach a critical mass of committers in the rules project; but here's some initial thoughts on typical 'extra' rulesets.
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