DRY is excellent advice within the context of a single function, service, or module. It is good advice; beyond that, I would extend DRY to the scope of a version control repository or a deployment pipeline. It comes at a cost, though. Sometimes this is a very significant cost when applied between services or modules, particularly if they are developed independently. The problem is that the cost of having one canonical representation of any given idea across a whole system increases coupling, and the cost of coupling can exceed the cost of duplication.
— David Farley, Modern Software Engineering
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