GitKraken
After downloading and moving Kaleidoscope into the Application folder, you are ready to configure it to work with GitKraken. Open the Integration window over Kaleidoscope application menu > Integration…
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In the Integration window, navigate to the Git section:
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First install the ksdiff command line tool, afterwords make Kaleidoscope Git's default diff and merge tool.
In GitKraken, open the Preferences by clicking the gear icon in the toolbar.
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In the General section, select Kaleidoscope as External Merge Tool and External Diff Tool:
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And that's it, you're all set to start using Kaleidoscope together with GitKraken.