JavaScript is the most costly resource we send to browsers; having to be downloaded, parsed, compiled, and finally executed. Although browsers have significantly decreased the time it takes to parse and compile scripts, download and execution have become the most expensive stages when JavaScript is processed by a web page.

Sending smaller JavaScript bundles to the browser is the best way to reduce download times, and in turn improve page performance. But how much JavaScript do we really use?

When it comes to frameworks and UI libraries, there are some interesting numbers. Given the volume of chatter in the dev world, you’d be forgiven for thinking that React is used on the majority of websites today. The real number? 4.6% of websites. That’s less than the number of websites using CSS custom properties.

This is reminding me of what I wrote about dev perception.

Monday, November 11th, 2019 12:22pm

Tagged with javascript report almanac usage frameworks libraries performance filesize frontend development

Limiting JavaScript? - TimKadlec.com

Following on from that proposal for a browser feature that I linked to yesterday, Tim thinks through all the permutations and possibilities of user agents allowing users to throttle resources:

If a limit does get enforced (it’s important to remember this is still a big if right now), as long as it’s handled with care I can see it being an excellent thing for the web that prioritizes users, while still giving developers the ability to take control of the situation themselves.

Friday, February 1st, 2019 4:12pm

Tagged with javascript throttling limiting browsers resources performance speed proposal feature frontend development bandwidth filesize