Performance Newsletter



Redesigning browser history

"Let me send you that link", "I think the website was blue at the top with a picture of the author… I think she was wearing a hat?" Remembering how you found something on the web seems to be almost impossible sometimes.

I really felt pink sparkle hearts (the most powerful of all emoji feelings) for Patryk Adaś’ approach to rethinking how browser history should work.

Go enjoy it. 



AWS Cloudfront launched HTTP/2 support!

Http/2 support was added to ELB not that long ago, so it just seemed like a matter of time until Cloudfront also supported H2.

H2 is on all new distributions, but for existing ones, you'll need to go turn it on.



How is so damn fast

If you haven't already seen it, check out (I'll wait right here).
Done? Yeah… fast, hey?

It impressed Sam Saccone too. (his tweet storm provides some insight to how they achieved such fantastic results 👍)

A lot of performance is gained by clever usage of webpack sharding, which is fantastic, because the Housing engineering team shared their development and production webpack configurations. Goldmine ☘



Title Case verses Sentence case

If you've read anything I've written, you might've noticed that I'm one of those Sentence case UI people. Title Case always felt so formal, yet incorrect… it sends a shudder down my spine even just thinking about it. Then I read this article. 

If you've always felt icky one way or the other, then you're going to enjoy this 🔡



16% of a JPEG is nothing but metadata

Inian Parameshwaran wrote in this week to share his findings of analysing 195GB of images from the top 500K websites.

Turns out, metadata (on average) equates to around 16% of the file size. Interesting report, worth a look.



Real world #perfmatters

I came across this tweet, which really made me grin. (Also, who goes to drive-thrus anymore?)

No one likes a long wait at the drive-thru.
Research: shaving 7 secs off of wait time = +1% sales increase.

Customer experience is everything. 



Don't use document.write()

It's been known for some time now that document.write is the worst way to add content / scripts / or anything(!) to a page because it blocks a browser's HTML parser from being able to read-ahead.

Chrome has had developer console warnings for a little while now, but soon it'll intervene with slow or lower powered devices, causing the document.write to be ignored completely. It's time to leave document.write back in the 90's where it belongs 🔥



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