A brief analysis and comparison of the CSS for Twitter's PWA vs Twitter's legacy desktop website. The difference is dramatic and I'll touch on some reasons why.

Legacy site *downloads* ~630 KB CSS per theme and writing direction.

6,769 rules
9,252 selectors
16.7k declarations
3,370 unique declarations
44 media queries
36 unique colors
50 unique background colors
46 unique font sizes
39 unique z-indices

https://t.co/qyl4Bt1i5x
PWA *incrementally generates* ~30 KB CSS that handles all themes and writing directions.

735 rules
740 selectors
757 declarations
730 unique declarations
0 media queries
11 unique colors
32 unique background colors
15 unique font sizes
7 unique z-indices

https://t.co/w7oNG5KUkJ
The legacy site's CSS is what happens when hundreds of people directly write CSS over many years. Specificity wars, redundancy, a house of cards that can't be fixed. The result is extremely inefficient and error-prone styling that punishes users and developers.
The PWA's CSS is generated on-demand by a JS framework that manages styles and outputs "atomic CSS". The framework can enforce strict constraints and perform optimisations, which is why the CSS is so much smaller and safer. Style conflicts and unbounded CSS growth are avoided.
How does the PWA do responsive design with 0 media queries? Modern responsive design is about conditionally rendering entire component trees, and making components adapt to their own dimensions. You need to use 'ResizeObserver' for that. Media queries in CSS aren't good enough.
In fact, putting state in CSS (:hover, @media, etc) is as much of a problem for dynamic web apps as putting state in the DOM. Removing state from style definitions simplifies coordinating changes to trees & styles, and opens the door to more native-feeling interactions.
The Twitter PWA is a good example of how a huge, highly dynamic app benefits from a simpler "styles in JavaScript" paradigm (powered by a subset of CSS) that is significantly more effective and reliable than working directly with CSS or CSS-in-JS.

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The entire discussion around Facebook’s disclosures of what happened in 2016 is very frustrating. No exec stopped any investigations, but there were a lot of heated discussions about what to publish and when.


In the spring and summer of 2016, as reported by the Times, activity we traced to GRU was reported to the FBI. This was the standard model of interaction companies used for nation-state attacks against likely US targeted.

In the Spring of 2017, after a deep dive into the Fake News phenomena, the security team wanted to publish an update that covered what we had learned. At this point, we didn’t have any advertising content or the big IRA cluster, but we did know about the GRU model.

This report when through dozens of edits as different equities were represented. I did not have any meetings with Sheryl on the paper, but I can’t speak to whether she was in the loop with my higher-ups.

In the end, the difficult question of attribution was settled by us pointing to the DNI report instead of saying Russia or GRU directly. In my pre-briefs with members of Congress, I made it clear that we believed this action was GRU.
I think about this a lot, both in IT and civil infrastructure. It looks so trivial to “fix” from the outside. In fact, it is incredibly draining to do the entirely crushing work of real policy changes internally. It’s harder than drafting a blank page of how the world should be.


I’m at a sort of career crisis point. In my job before, three people could contain the entire complexity of a nation-wide company’s IT infrastructure in their head.

Once you move above that mark, it becomes exponentially, far and away beyond anything I dreamed, more difficult.

And I look at candidates and know-everything’s who think it’s all so easy. Or, people who think we could burn it down with no losses and start over.

God I wish I lived in that world of triviality. In moments, I find myself regretting leaving that place of self-directed autonomy.

For ten years I knew I could build something and see results that same day. Now I’m adjusting to building something in my mind in one day, and it taking a year to do the due-diligence and edge cases and documentation and familiarization and roll-out.

That’s the hard work. It’s not technical. It’s not becoming a rockstar to peers.
These people look at me and just see another self-important idiot in Security who thinks they understand the system others live. Who thinks “bad” designs were made for no reason.
Who wasn’t there.

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THIS.

Russia hasn't been a willing partner in this treaty for almost 3 decades. We should have ended the pretense long ago.

Naturally, Rand Paul is telling anyone who will listen to him that Trump is making a HUGE MISTAKE here.


Rand is just like his dad, Ron. 100% isolationist.

They've never grasped that 100% isolationist is not 'America First' when you examine it. It really means 'America Alone'.

The consistent grousing of pursuing military alliances with allies - like Trump is doing now with Saudi Arabia.

So of course Rand has also spent the last 2 days loudly calling for Trump to kill the arms deal with Saudi Arabia and end our alliance with them.

What Obama was engineering with his foreign policy was de facto isolationism: pull all the troops out of the ME, abandon the region to Iranian control as a client state of Russia.

Obama wasn't building an alliance with Iran; he was facilitating abandoning the ME to Iran.

Obama wouldn't even leave behind a token security force, so of course what happened was the rise of ISIS. He also pumped billions of dollars into the Iranian coffers, which the Mullah's used to fund destabilizing activity [wars/terrorism] & criminal enterprises all over the globe