Ooo…this is smart. Ire explains why you should use the :lang pseudo-class instead of the [lang=''] attribute selector.
Fantastic post from Marcy about the consequences of the way we build, and how we can improve.
Pat has been doing some intense research around HTTP/2 prioritization which lead to this magnificent post discussing how each browser handles priorities (not well, for the most part) and also provides a handy test page for checking how CDN’s and servers are doing.
Andy has already taken that page and started tracking how CDN’s are doing (again, not well for most of them).
While ever you build under the assumption that things will always work smoothly, you’re leaving yourself completely ill-equipped to handle the scenario that they don’t.
I rather like Scott’s term for what happens when you use client-side JavaScript for A/B testing.
This pattern leads to such a unique effect on page load that at last week’s Perf.Now() Conference, I coined a new somewhat tongue-in-cheek performance metric called “Second Meaningful Content,” which occurs long after the handy First Meaningful Content (or Paint) metric, which would otherwise mark the time at which a page starts to appear usable.
Brucey-kins on how semantic markup like <strong> and <em> is interpreted by screenreaders.
Lovely performance “postmortem” from Eli Fitch about how MapBox got their first-meaningful-paint to drop from 4.7s to 1.9 seconds.
Some good insights into technical optimizations, but as always, the cultural aspects are the most difficult–and the most important.
Nurturing cultural awareness and enthusiasm for building fast, snappy, responsive, tactile products is arguably the most effective performance improvement you can make, but can be the most challenging, and requires the most ongoing attention.
Cennydd expands on something he discussed in his (excellent) book, Future Ethics: why hiring a chief ethics officer may not be a particularly effective approach.
A chief ethics officer would be too distanced from product and design orgs, where most ethical decisions are made; their duties would come into conflict with those of the CFO, who is already on the hook for financial ethics; and the seniority of the role would mean this person would be seen as an ethical arbiter, an oracle who passes ethical judgment. This is IMO a failure state for ethics. Loading ethical responsibility onto a sole enlightened exec doesn’t scale, and it reduces the chance of genuine ethical discourse within companies by individualising the problem.
I like Harry’s categorization for performance testing:
I try to distill the types of testing that we do into three distinct categories: Proactive, Reactive, and Passive.
I’ve been using “Active” and “Passive” myself and found that it really helps companies better understand why having both synthetic and RUM monitoring in place is important. I really like the way Harry breaks that “Active” category out further based on whether the tests are run proactively or reactively.
Removing the Base64 encoded font has reduced the total page weight by 16% (75 KB) per request (assuming no caching). This may not sound like a huge difference, but GOV.UK receives approximately 48 million visitors per month, so this adds up to mobile users saving approximately 800 GB per month, cumulatively. This is especially important to users on older mobile devices and expensive data plans.