Bundling JavaScript for Performance: Best Practices

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Chris Coyier on (Updated on )

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Performance advice from David Calhoun on how many scripts to load on a page for best performance:

[…] some of your vendor dependencies probably change slower than others. react and react-dom probably change the slowest, and their versions are always paired together, so they both form a logical chunk that can be kept separate from other faster-changing vendor code:

<script src="vendor.react.[hash].min.js"></script>
<script src="vendor.others.[hash].min.js"></script>
<script src="index.[hash].min.js"></script>

Funny how times haven’t changed that much! Me, in 2012, talking about how many CSS files need to be loaded on any given page: One, Two, or Three. I split it into global, section-specific, and-page-specific so it was less about third-party code, although that could certainly apply, too.

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