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The term drop in place refers to the concept that the deployer should be able to drop the new code in place and not encounter surprises. (This is conceptually similar to "adding functionality in a backwards compatible manner".) Changes are not drop in place when they affect the behavior of the system in a way that is unexpected by an administrator, user, or automated (API) client, and that require actions to be taken on behalf of the affected party. Examples of such changes include:
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