but there isn&#x27;t 1 CDN, or 1 version... if you need two libraries, but the canonical CDN for jquery is on one, and your required extension is on another... that&#x27;s two DNS lookups, connections, request cycles, etc.<p>So you use the one that has both, but one is not canonical, which means more cache misses.  That doesn&#x27;t even count the fact that there are different versions of each library, each with it&#x27;s own uses, and distribution, and the common CDN approach becomes far less valuable.<p>In the end, you&#x27;re better off compositing micro-frameworks and building yourself.  Though this takes effort...  React + Redux with max compression in a simple webpack project seems to take about 65K for me, before actually adding much to the project.  Which isn&#x27;t bad at all... if I can keep the rest of the project under 250K, that&#x27;s less than the CSS + webfonts.  It&#x27;s still half a mb though... just the same, it&#x27;s way better than a lot of sites manage, even with CDNs