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If you don't have Node.js and npm set up, you'll need to do so. If you're using OS X, we can recommend using the Homebrew package manager, and installing its node package. [I have found since first writing this document that it's nicer to use NVM (Node Version Manager, see also). --mb] (That will give you both node and npm.) After you've installed npm, you can install elasticdump by following the instructions in its README.
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