The Failed Promise of Web Components

Web Components are a total mess and impossible to build anything of significance with. I can't even imagine how anyone would get anything done with them. It's like an Angular developer, an artist, and a mid-2010s neural net walked into a bar and sketched out a spec by taking shots and passing it clockwise.

Separation of languages is a silly way to separate things. You're building components: logic, structure and style are coupled. SwiftUI adopts the React model, and it succeeds because of it. One can build an app in React/SwiftUI in about 1/2 the time spent "separating concerns", and build systems still extract things out to be clean and performant, there's no sacrifice being made there. CSS is a shitshow and a total mess especially on large teams.

React has nothing to do with how performant an app is and if anything speeds them up compared to anything previously, you may be confusing the power and ease with which it enables development as getting some drunk on building larger apps, but that's only because of how effective it is. Twitter is a good example, great performance. It's way more about the team than the tool, though certainly it will get easier over time to have the defaults be better at optimization for smaller teams who are ambitious.

Most of the super bloated websites I see are basically news sites and other less-techy sites that are stuffed with ad tracking and have no tree shaking. The majority of React apps build with Webpack which supports tree shaking and lazy loading out of the box, plus React makes it possible to pre-render your entire app and deliver it as HTML that hydrates.

I've built several complex apps (which I suppose are "of significance") with web components. I just used a framework (Polymer in my case) to abstract away the web components API.

I have never used SwiftUI so I can't comment on it. However, separation of concerns doesn't need to take extra development time. Inlining all CSS and JS is like dropping the MVC model because creating all the necessary classes is taking too much time; focusing on short term gains only lead to a mediocre end result, one that nobody wants to maintain five years down the line.

Good React is fine for large applications, but not for websites. Even in applications a few lines of Javascript and a rendering backend can replace entire JS frameworks. Try disabling Javascript for a day and you can see how many pages just become a white screen because whatever is replacing the browser's renderer isn't loading.

> Twitter is a good example, great performance.

I agree that it's a great example, but it performs horribly for me. I use their website on my phone and videos rarely play back properly, content jumps around while navigating, empty screens and loading bars are everywhere. Sometime I just have to reload because the Twitter website decided it doesn't want to load images anymore. Nitter links, on the other hand, load instantly, including image and video content, because of its minimalist approach.

Server side rendering is a welcome improvement because it means the developer doesn't offload the website's calculations to their visitors. I'm fine with whatever framework people pick on the server, as long as my browser doesn't get its rendering engine replaced by the fancy framework for the week.

React is a nightmare when it comes to performance or energy efficiency...

Downloading 500kb of js and processing this is just a nogo. The best advice to anyone interested in page speed, dont use this crap.

https://youtu.be/plt-iH_47GE

Use Gatsby and generate a static site w/ React? At least React is faster than Angular, which I strongly prefer.

My website which is entirely built in react (and uses Gatsby).

Takes 4kb to full page render (1 file - static only - JavaScript disabled).

That’s smaller than most any html+css especially if using some css library.

Of course once that is loaded and if JavaScript is enabled, then it will start to load interactive stuff and prefetch (which is around 100kb - but I have a lot of interactive stuff - including a zork style adventure Easter egg in the site header).

Weird, because we're using web components at my workplace to build complex web applications. We use Lit-Element as a base class and have come up with a top-down functional state pattern for data that removes the need for two-way binding. If a sub-component needs to update its state due to DOM interaction, it just fires off an event with info about that DOM interaction, and the data store for that component (another web component) does the necessary state modification, then fires off a "state-changed" event that tells all associated components to update their state from the "master" store (one line of code). All of the data elements use pure functions to do state modification, so doing complex operations is simply a matter of composing the appropriate functions. I've not used react myself other than playing with a few demos, but another developer on my team says the pattern is very similar to how react stores work, and the core modules that drive it are like 100 lines of code.

Check the time to interactive. Rehydration creates a massive cpu increase.

https://developers.google.com/web/updates/2019/02/rendering-...

Lit-Element puts lipstick on the low level pig, but React excels in many ways beyond it. Consistency between props (vs attributes), can render server side, awesome side effect system that makes it world class at hmr.

I think WebComponents have left a horrible taste in the mouth because they came well after React and others existed, didn’t take any inspiration or provide any abstractions that would help, did basically everything worse and seemingly without any discussion with real world devs, and then were hyped and pushed on everyone for years while they basically lacked all necessary features. Now, years later they have evolved and added libraries on top to smooth over all the weirdness, and if you squint they look similar, but the web would have been a better place if they had just provided some VDOM abstractions, style containment in a simple way, and so on rather than master-planned a High Modernist dystopia and then slowly painted over it until it resembled something like the organic cities that already existed.

Writing inline styles != rendering inline styles, look at “atomic style extraction” which with a compile step gives you far better results: automatic dead code elimination, automatic partial loading that’s tied directly to your usage, and no more jumping between the thing you’re styling and the the thing itself.

The nitpicks you have on Twitter are on specific behaviors (video and jumping and slow fetch) that have nothing to do with React. The site itself is lightweight and runs fast.

In lighthouse, I see a score of 100 performance and time to interactive at 1.8secs.

This is comparable to hacker news home page (which is purely static), but my first contentful paint was slightly faster (probably because my site is slightly smaller).

Both sites were about 4 times faster (TTI) than google home page and typescript home page.

I guess maybe you had a different experience than I did, because I never had web components "pushed" at me in any way. It was always a technology I was keeping my eye on but was hesitant to invest in until the browser support was there, and now that the browser support arrived I've seen a grand total of ONE web-component-focused talk at the web dev conferences I've attended, and that one was given by our project lead.

I've tried LitElement (still using it in a small project), and wanted to like it; but the whole experience was so cumbersome compared to something like React.

1) Classes for writing components. Yuck. React's function component feels much more elegant.

2) @property decorator. Double yuck! I want a reactive way of updating my component's state without having to declare this piece of state as a property accessible by the outside world.

3) this.requestUpdate(). Triple yuck compared to something like React's setState or useState hook.

4) In order to create children components, I need to create more customElement-decorated classes? Yuck again!

I’d be interested in checking out your site. I normally only have a 2G connection on my phone, I’d love to be able to read something that’s NOT HN. This site is the only site I know that takes less than 5-10 mins to load, if it loads at all.

> Downloading 500kb of js and processing this is just a nogo.

React + react-dom is under 40kb minified gzipped. The other 460kb are your responsibility.

Ok, here it is https://ricklove.me

Here is a post that explains some of the content that is interesting: https://ricklove.me/cool-stuff

Let me know how it does on a slow connection.

I think the irony here is that MVC in its original form has largely fallen out of fashion the last few years. And it is precisely because physically separating all of the functionality into a model/view/controller files doesn't actually make development easier. This makes sense right? Logically it's all coupled, so separating the pieces, even if they are functionally responsible for different things, doesn't really produce a system that is easier to maintain.

Look at the new default "razor pages" web project for .NET core. While it it is a little bit fancier, it basically brings back the same mental model that PHP has been using for decades. That is, cram all of the logic into a single file, and use a "service locator" pattern (I know it's actually DI under the hood) to "inject" extra functionality. In this way it is easy to trace where all of the pieces are coming from. Why abstract your `UserRegistrationView` to accept any `UserRegistrationModel` from a `UserRegistrationController` in a "decoupled" manner when the reality is that only one of any of that actually needs to exist ever? Might as well have the orchestration right next to the use-case!

The above applies to (what I believe to be) a significant majority of use-cases. At least the interesting ones.

MVC - because spending 50% Of your time looking for the other file with the almost identical name is fun... wait now we need the view... nope back to the controller again... why can’t these files be next to each other...

It’s ironic that this is done in the name of “Separation of concerns“ -

You know what separates concerns: having everything that affects this component - in one place. That’s true separation of concerns.

I’ve worked in multiple frameworks in multiple languages and nothing does it better than modern react (especially with webhooks).

> I think the irony here is that MVC in its original form has largely fallen out of fashion the last few years.

Not really — unless React is the only library you use.. MVC is still the best pattern. If you are an iOS developer you may already be familiar with MVC in Cocoa. Most UI frameworks, including ASP.NET Core, JSP and JSF (Java based frameworks), Ruby on Rails, and Django (Python) are all based on MVC. That's no accident. These disparate platforms — mobile and Web — all converged on MVC because it is the best architectural pattern for developing user interfaces.

There’s a whole ecosystem of alternatives that have sprung up I have a feeling you haven’t tried (not MVVM or anything like that). Without appealing to any of them you aren’t convincing.

Even within the frontend world and not in React you have all sorts of new state systems and structures that are in my opinion far more intuitive, less code, less cross cutting concerns, easier to change and grow more naturally. The gist of it is either a global state store with cursors and namespaces (I like this less than most) or a global state system with state split out (see Recoil) or an entirely tree based reactive state system (see mobx-state-tree or mobx-store) or even just nesting reducers or any simple nesting state container (pure react, zustand). I’ve recently put together gqless[0] with a state system similar to recoil but simpler (sort of like use-atom). It’s wonderful.

Your data is a tree/graph, you app is a tree, your file system is a tree, everything matches. You just slot in state with corresponding actions and at the level of the view hierarchy where it first becomes relevant (router at top, view controllers are spread in the middle layers however needed, and leafs get their own state as needed). And all data level things stay up in the graph, which I guess you could argue is an M sitting above it all, the VC are blurred together with more C at the top of the tree and pure V at the leafs. Even styling is all encapsulated where it’s used. Each piece is a lego block that can be moved around. And yes, it works, and works well, even without all the handlebars of Rails.

Wouldn’t dream of going back. It’s perhaps not a mature enough ecosystem for most to navigate their way to getting a good DX on a stack like that. Many pieces have rough edges if you don’t know what to avoid, it’s not like these huge mature frameworks that keep you away from scary stuff but also box you into a rigid structure. But of course it means you can do all sorts of things unimaginable in MVC land.

The reality shows totally different numbers https://perf-track.web.app/react

That is really a great website. Why didn't you built that site with HTML?

Just check the stats here: https://perf-track.web.app/react

I'm quite sad that hunter2 isn't in your passwords.txt

It’s not a static site.

Type “dir” in the header (or other activities in the “cool-stuff” post).

Moreover, I can build anything I want very quickly - with great engineering - and still get performance comparable to a static site.

Good idea :) I’ll add that.

I guess I’ll know if someone finds the Bitcoin.

Update: I added a few more nerd lore passwords - thanks for the idea!

It took 30s to 60s to fully load, but the content was available very quickly. The most entertaining thing was the stripe example. I didn’t realize it was supposed to load the card form, so I hit subscribe and it caused an error (because the card form wasn’t loaded yet) but the app handled it appropriately. It would be better if the subscribe button were disabled before the component loaded (which took at least a minute), but it’s still pretty good.

Overall, it was a very refreshing experience.

Ah, makes sense on the stripe component.

I did notice that for some components I need to show a loading indicator while they are loading async (for a slow connection).

Thanks for letting me know!

> Twitter is a good example, great performance

This statement alone invalidates your arguments, because evidently you never once tried opening Twitter on an underpowered machine, be that desktop or a phone.

Most of the frameworks you mention above are 5+ years old. Back when jQuery was the THE THING to know.

In any case, my critique is not levied against MVC the pattern, rather, how it is manifest. One can logically follow MVC without the physical separation of concerns (files). It's a continuum: You start by defining your state, view, and orchestration all in the same place. Should any one piece of the above suddenly need to be reused elsewhere, you then abstract as necessary.

I was pushing back against the idea that "inlining" CSS/JS with HTML is poor practice. What React achieves, because it demands you inline JS (and CSS if you want) with the HTML, is a simple, declarative development paradigm. It's like reading a function. No procedural ad-hoc `let el = document.querySelector('#id')` garbage getting in the way. The behavior is with the component, not around the component. In many ways, this is how OOP was supposed to work.

Better, generate a static site without frameworks.

Could you give a few examples of those languages and frameworks just to understand what you are comparing React to?

Here’s a decent list through time for JavaScript frameworks: http://todomvc.com/

For my own experience with things that were specifically MVC or MVVM:

In C#: Asp.net MVC, WPF (with/without Prism)

In Typescript: Knockout, Angular 2.0+ (I guess it wasn’t mvc really - I disliked it for other reasons)

React (with hooks) on the other hand is the embodiment of a pure Functional Programming UI.

I can literally write a component with a single import and a single function.

For every reason functional patterns beats OOP patterns, react beats mvc - and achieves true separation of concerns (feature aligned concerns).

Yes, every word

Thanks, that helps.