ExtIdForAll
Handy metadata set that add an External ID field for all fields in the standard configuration of a new Salesforce org.
Contains a set of metadata records for all salesforce objects that you'll get with a clean install. Just push the content of this repo to your new org and you'll get a custom field (ExtId__c) that comes as a handy helper if you'll do data import later. I need this a lot, and I hate creating fields by hand. So I started doing this with a single deployment like this:
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