I’ve always like Jeremy’s categorization of developer tools:
I’ve mentioned two categories of tools for web development. I still don’t know quite what to call these categories. Internal and external? Developer-facing and user-facing?
The first category covers things like build tools, version control, transpilers, pre-processers, and linters. These are tools that live on your machine—or on the server—taking what you’ve written and transforming it into the raw materials of the web: HTML, CSS, and JavaScript.
The second category of tools are those that are made of the raw materials of the web: CSS frameworks and JavaScript libraries.
It’s a good way to think about things. There is nuance though, naturally. Sass is the first category since Sass never goes to users, it only makes CSS that goes to users. But it can still affect users because it could make CSS that is larger or smaller based on how you use it.
Jeremy mentions Svelte as a library where the goal is essentially compiling as much of itself away as it can before code goes to users. Some JavaScript is still there, but it doesn’t include the overhead of a developer-facing API. The nuance here is that Svelte can be used in such a way that all JavaScript is removed entirely. For example, SvelteKit can turn off it’s hydration entirely and do pre-rendering of pages, making a site that entirely JavaScript-free (or at least only opting in to it where you ask for it).
On React:
I know there are ways of getting React to behave more like a category one tool, but it is most definitely not the default behaviour. And default behaviour really, really matters. For React, the default behaviour is to assume all the code you write—and the tool you use to write it—will be sent over the wire to end users.
I think that’s fair to say, but it also seems like the story is slowly starting to change. I would think widespread usage is far off, but Server Components seem notable here because they are coming from the React team itself, just like SvelteKit is from the Svelte team itself.
And on Astro:
[…] unlike Svelte, Astro allows you to use the same syntax as the incumbent, React. So if you’ve learned React—because that’s what you needed to learn to get a job—you don’t have to learn a new syntax in order to use Astro.
I know you probably can’t take an existing React site and convert it to Astro with the flip of a switch, but at least there’s a clear upgrade path.
This isn’t just theoretically true, it’s demonstrably true!
I just converted our little serverless microsite from Gatsby to Astro. Gastby is React-based, so all the componentry is already built as React components. The Pull Request is messy but it’s here. I converted some of it to .astro files, but left a lot of the componentry largely untouched as .jsx React components. But React does not ship on the site to users. JavaScript is almost entirely removed from the site, save for some hand-written vanilla JavaScript for very light interactivity.
So there is some coin-flipping stuff happening here. Coin merging? Astro to me feels very much like a developer-facing tool. It helps me. It uses the Vite compiler and is super fast and pleasant to work with (Astro has rough edges, for sure, as it’s pre 1.0, but the DX is largely there). It scopes my styles. It lets me write SCSS. It lets me write components (in many different frameworks). But it also helps the user here. No more JavaScript bundle on the site at all.
I guess that means Astro doesn’t change the categories—it’s a developer-facing tool. It just happens to take what would be a user-facing tool (even Svelte) and makes them almost entirely developer-facing.
And just because I’ve had a couple of other Astro links burning a hole in my pocket, Flavio has a good intro tutorial and here’s Drew McLellan and Matthew Phillips chatting Astro on a recent Smashing Podcast.
And here’s Dave and I chatting about my recent little site-re-do in Astro: