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README.md

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 - [Tumblr Shares Database Migration Strategy With 60+ Billion Rows](https://newsletter.systemdesign.one/p/how-to-migrate-a-mysql-database)
 - [Software Engineer Interview Learning Resources](https://systemdesign.one/software-engineer-interview-learning-resources/)
 - [7 Simple Ways to Fail System Design Interview](https://newsletter.systemdesign.one/p/design-system-newsletter)
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+## License
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+<p>Licensed under <a href="https://creativecommons.org/licenses/by-nc-nd/4.0/" target="_blank" rel="license noopener noreferrer" style="display:inline-block;">CC BY-NC-ND 4.0</p>