Loosely running with your example: A file already exists with this content: [{"cmd": "git checkout", "when": 1234 }] Another tool wants to add a setting/elem

Loosely running with your example: A file already exists with this content: [{"cmd": "git checkout", "when": 1234 }] Another tool wants to add a setting/element/etc, and simply creates a new config object with only the change in question included and APPENDS the existing config. [{"cmd": "git checkout", "when": 1234 }][{"cmd": "vagrant up", "when": 4567},{"comment": "Comments, notes, etc are kept even if they don't validate to the recognized configuration options."}] A configuration validator / etc loads the config and merges these in state-machine order, over-writing existing values with the latest ones from the end of the stream of objects and then determining if the result is a valid configuration. (Maybe file references fail to resolve / don't open / there's some combination of settings that's not supported...) [ {"cmd": "git checkout", "when": 1234 }, {"cmd": "vagrant up", "when": 4567}, {"comment": "... actually kept as above"} ]