Ryosuke

Posted on Oct 7, 2022 • Originally published at whoisryosuke.com

Migrating my Gatsby MDX blog to AstroJS (and why you shouldn't)

#astro #tutorial #react #javascript

It’s that time again. The initial commit on the last version of my Gatsby-based site was Mar 30, 2018, and the last major redesign was October 14th 2019. It’s been 3 years since I last touched the design of the site, so as a designer you can imagine I’ve been reeling waiting to change things up.

But I’ve also been quite busy lately between work and life, so I haven’t had the time to invest in the wild and ambitious redesign I’ve been envisioning for the past year or so. To keep things moving, I opted to do a mini redesign or a “refresh” where I kept things as simple as possible.

My goal was to try a few new libraries and get experience under my belt (cause isn’t that what dev blogs are for?). I’d swap out Gatsby for **Astro,** and Styled Components + Styled System for **Vanilla Extract**. I was interested in trying Astro as it just hit 1.0, and I’ve been experimenting for a while with Vanilla Extract as a way to write Typescript powered styles and export to CSS.

In case you’re looking at an archived version of this post in the distant future, here’s a preview of what the redesign looked like:

I’ll break down a bit of my redesign process and some of the issues that tripped me up along the way.

The Process

I started initially in code. Then designed a rough and finalized version in Figma. Then brought the design to life in Astro, React, and Vanilla Extract.

Gatsby to Astro

I had a framework from my Gatsby website to work with, and I needed to figure out how to migrate that content to another framework without too much effort. All my content is in MDX files, mostly Markdown with a few files using some custom React components (like a <Box> for layout).

At first, I wasn’t sure I was going to use NextJS or Astro. But Astro won me over once I saw how plug and play the Markdown and MDX support was with a couple of plugins (even frontmatter! which lots of stuff struggles with).

I learned a bit about how Astro works while prototyping a very rough and unstyled version of the blog. I started with a single blog post to see how things carried over. Things seemed good, so I proceeded with the design phase in Figma.

Figma Design

This was probably the chillest part of the process. I had 2 mood boards I’d been accruing over months, one for an ambitious redesign and one for a simpler one. I took a look at those, and dug around for a bit more inspo.

The first round didn’t deviate too far from where we ended up. I had a fairly clear vision of what I wanted, but the minor elements just needed to fall into place.

I got a little distracted trying to incorporate texture into the website…

But I eventually landed on using a 3D animation as the primary background element. I found an abstract 3D render on a stock image website and figured I could recreate something similar in ThreeJS / R3F.

With the design in place, I moved back over to the code to develop the design system and components.

Vanilla Extract with Sprinkles please

I started to develop some of the components in isolation using Storybook and Vanilla Extract. I used one of my previous projects as the basis, Gelato UI, a design system I created using Nx monorepo.

After finishing all the components here, I copied them over to my Astro website.

It actually wasn’t that simple initially though — when I was working on the design system, Astro didn’t support Vanilla Extract (even as a pre-compiled 3rd party library). Luckily someone updated the Vanilla Extract Vite plugin (which Astro uses under the hood).

Time to surf 3D waves

For this part it was pretty straightforward since I had a 3D design I was using as the basis. I opened up CodeSandbox and forked one of my old R3F sandboxes that had a custom shader material.

I created a cube (or box) and formed it into a long rectangle (like strips of paper). I made sure to increase the number of “segments” in the box so it’d animate a bit smoother.

import React, { useMemo, useRef } from "react";
import { MeshProps, useFrame } from "@react-three/fiber";
import { Line } from "@react-three/drei";
import "./material";

type WaveProps = MeshProps & {
  offset: number,
};

// The box/cube parameters
const WAVE_SIZE = {
  width: 0.5,
  height: 10,
  depth: 0.05,
  // How "subdivided" the mesh is (aka bigger number = more polygons)
  widthSegment: 2,
  heightSegment: 32,
};

function Wave({ offset, ...props }: WaveProps) {
  const geom = useRef();
  useFrame((state) => {
    // Send (and update) "uniforms" or data to the shader (like the time)
    geom.current.material.uniforms.time.value = state.clock.getElapsedTime();
    geom.current.material.uniforms.offset.value = offset;
    // geom.current.geometry.verticesNeedUpdate = true
  });

  return (
    <mesh
      ref={geom}
      rotation={[-Math.PI / 2, 0, 0]}
      castShadow
      receiveShadow
      {...props}
    >
      <boxBufferGeometry
        args={[
          WAVE_SIZE.width,
          WAVE_SIZE.height,
          WAVE_SIZE.depth,
          WAVE_SIZE.widthSegment,
          WAVE_SIZE.heightSegment,
        ]}
      />
      <waveMaterial />
      {/* <meshBasicMaterial wireframe /> */}
    </mesh>
  );
}

export default Wave;

Now that I had a wave, I just had to create a component that makes a bunch more. I make an empty array of 9 items and map over it with each <Wave /> component.

import React from "react";
import Wave from "../Wave/Wave";

const Waves = () => {
  const waves = new Array(9)
    .fill(0)
    .map((_, index) => (
      <Wave key={index} position={[index * 0.6, 0, 0]} offset={index} />
    ));

  return waves;
};

export default Waves;

Then the magic (or animation) happened in the shader. Essentially the boxes animate using time as a variable (so as time progresses, the variable changes). We take that time and use a sin() calculation to make it fluctuate between 0 and 1 (instead of going from 0 to Infinity). This makes the math a bit easier for stuff since it loops from 0 to 1 and back to 0 looping infinitely.

We apply the animation to the z index, so it only animates vertices in the z direction (up and down in this case). And it’s offset using an offset variable, so all the waves don’t animate at the same pace. That variable is the array index we loop over to make waves (aka 0-9).

float z = position.z + sin(position.y + time + offset);

Here is a version with the wireframe enabled as a visual aid:

After the scene was laid out and animated, I took some time to make to look better. This included lighting the scene, placing the camera, and adding post processing effects (like a bokeh).

For the post processing I used @react-three/post-processing components, and to get the look just right I created a debug panel using Leva to adjust some values (like bokeh blur).

Custom shadow shader

Adding shadows (castShadow and receiveShadow) to all the objects helped give some depth — but I immediately noticed that my custom shader didn’t apply any shadows to the objects. After a bit of research, I found that the standard ThreeJS materials (like MeshPhongMaterial) have shadow calculations built into them. But when you create a custom shader, it’s a completely blank slate.

In order to add shadows, I had to copy and paste the shadow related code from the default ThreeJS materials (or shaders really).

import * as THREE from "three";
import { extend } from "@react-three/fiber";
import { mergeUniforms } from "three/src/renderers/shaders/UniformsUtils.js";
import { UniformsLib } from "three/src/renderers/shaders/UniformsLib.js";

class WaveMaterial extends THREE.ShaderMaterial {
  constructor() {
    super({
      transparent: true,
      // Enable fog/light/dithering maps to get passed to shader
      fog: true,
      lights: true,
      dithering: true,
      // wireframe: true,

      // Merge in the light and fog uniforms with any of your custom ones
      uniforms: mergeUniforms([
        { time: { value: 1 }, offset: { value: 0 } },
        UniformsLib.lights,
        UniformsLib.fog,
      ]),
      vertexShader: `
      // Include the shadow scripts
    #include <common>
    #include <fog_pars_vertex>
    #include <shadowmap_pars_vertex>

      uniform float time;
      uniform float offset;
      attribute float size;
      void main() {

          // Include the shadow scripts
        vec3 objectNormal = vec3( normal );
        vec3 transformedNormal = normalMatrix * objectNormal;
        #include <begin_vertex>
        #include <project_vertex>
        #include <worldpos_vertex>
        #include <shadowmap_vertex>
        #include <fog_vertex>

                // Do what you need (in this case, makes wave animation)
        float x = sin(position.x);
        float y = position.y;
        float id = position.z;
        float z = position.z + sin(position.y + time + offset);
        vec3 pos = vec3(position.x, position.y, z);
        gl_Position = projectionMatrix * modelViewMatrix * vec4(pos, 1.0 );
      }`,
      fragmentShader: `
      // Include the shadow scripts
      #include <common>
      #include <packing>
      #include <fog_pars_fragment>
      #include <bsdfs>
      #include <lights_pars_begin>
      #include <shadowmap_pars_fragment>
      #include <shadowmask_pars_fragment>
      #include <dithering_pars_fragment>

      uniform float time;
      void main() {
        // CHANGE THAT TO YOUR NEEDS
        // ------------------------------
        vec3 finalColor = vec3(0.95, 0.95, 0.95);
        vec3 shadowColor = vec3(0, 0, 0);
        float shadowPower = 0.5;
        // ------------------------------

        // it just mixes the shadow color with the frag color
        gl_FragColor = vec4( mix(finalColor, shadowColor, (1.0 - getShadowMask() ) * shadowPower), 1.0);
        #include <fog_fragment>
        #include <dithering_fragment>
      }`,
    });
  }
}

extend({ WaveMaterial });

This introduced a “banding” to my objects, which is technically incorrect I’m sure, but it looked kinda cool so I was ok with it.

You can find the final sandbox here for reference.

Light vs Dark mode

In the final site I also had to add a shader uniform to let the shader know if it was light or dark mode on the site.

// Get theme value from Zustand store
const { mainNav, theme } = useStore();

// Change color based on theme
const WAVE_PROPERTIES = {
  color: {
    light: new Color({
      r: 0.95,
      g: 0.95,
      b: 0.95,
    }),
    dark: new Color("#000"),
    hovered: new Color("#001BD8"),
  },
};
const themeColor =
  theme === "light" ? WAVE_PROPERTIES.color.light : WAVE_PROPERTIES.color.dark;

useFrame((state) => {
  geom.current.material.uniforms.color.value = themeColor;
});

Hover interaction

Once I had the 3D in place, I wanted to include some sort of interaction with the user. So when the user hovers over a navigation item, it “highlights” a specific wave by changing it’s color. This was pretty simple, I just set some onMouseEnter and onMouseLeave props to sync which nav item was active to the store.

const { mainNav, setMainNav } = useStore();

const clearHover = () => {
  setMainNav("none");
};

return (
  <MainNavItem
    href="/blog"
    onMouseEnter={() => setMainNav("writing")}
    onMouseLeave={clearHover}
  >
    Writing
  </MainNavItem>
);

Then inside the 3D I grab the menu items and use a little math to pick a wave to color:

const NAV_TO_INDEX: Record<MainNavNames, number> = {
  none: 0,
  writing: 1,
  work: 2,
  resources: 3,
  playlist: 4,
};

const { mainNav, theme } = useStore();

// There's 18 waves, we want to do nearest ones and skip between
// Take the NAV_TO_INDEX and multiply by 2 to adjust for spacing
// And we add 8 to offset it enough to be in camera view
const isColored =
  mainNav !== "none" && offset === NAV_TO_INDEX[mainNav] * 2 + 8;

useFrame((state) => {
  if (isColored) {
    geom.current.material.uniforms.color.value = WAVE_PROPERTIES.color.hovered;
  } else {
    geom.current.material.uniforms.color.value = themeColor;
  }
});

This effect was pretty simple and made the site a bit more fun to use.

Astro, blast off!

With a final design and components in place, I started to lay out the various pages of the site. I had already roughly created the blog page, but I finished styling it, and moved on to the index page, then archive pages (blog and tags), and finally a playlist page.

This process was full of frustration as I learned the Astro ecosystem and adapted to it. There were a lot of really simple things I wanted to do (like wrapping components in React Context providers) that would break the entire app. Most of these issues are described below. A lot of the issues I had were definitely a little niche in some cases, but I do think that a lot of users will expect to do most if not everything I did.

Astro-nomical Issues

Vanilla extract support

As I was creating the blog initially, there was no Vanilla Extract support. I mentioned it on Twitter and in the same day someone mentioned they had just patched the Vanilla Extract Vite plugin to support Astro.

Updated my dependency and it worked like a charm.

Although it has been a bit buggy? Occasionally pages will load with none or incorrect styles, and require a reboot to the dev server to correct. This is probably something that’ll get patched down the line since everything is so fresh hot 👍

MDX Provider not supported out of box

Had to find a custom Astro plugin script to do it. It essentially is a middleware for the MDX and it goes in does a simple “find and replace” on the exported JS. This works well, but it tends to crash the dev server randomly with a “maximum call stack exceeded” error 🤷‍♂️

// astro.config.js
import { defineConfig } from "astro/config";
import react from "@astrojs/react";
import { vanillaExtractPlugin } from "@vanilla-extract/vite-plugin";

import mdx from "@astrojs/mdx";

// Swap out elements in MDX file with React components
// e.g. `<p>` becomes `<Text>`
const mdxProvider = () => {
  return {
    name: "mdx-components-provider",
    enforce: "post",
    transform(code, id) {
      if (!id.endsWith(".mdx")) return;
      code = `import { components } from '@/components/MDXComponents/MDXComponents';\n${code}`;
      code = code.replace(
        "export default MDXContent;",
        `
        export default function (props) {
          const newProps = {
            ...props,
            components
          }
          return MDXContent(newProps);
        };`
      );
      return code;
    },
  };
};

// https://astro.build/config
export default defineConfig({
  markdown: {
    shikiConfig: {
      theme: "material-palenight",
    },
  },
  // Enable React to support React JSX components.
  integrations: [react(), mdx()],

  vite: {
    // Example: Add custom vite plugins directly to your Astro project
    plugins: [vanillaExtractPlugin(), mdxProvider()],
  },
});

// MDXComponents.tsx
import Box from "../Box/Box";
import Text from "../Text/Text";

export const components = {
  h1: (props) => (
    <Box mt={7}>
      <Text as="h1" fontFamily="heading" fontSize={5} {...props} />
    </Box>
  ),
  div: (props) => <Box {...props} />,
};

Can’t use render props inside `.astro` files

Tried to create a component that accepts another React component as a prop (<Accordion title={<Text>Title</Text>}>) and the compiler did not like it, crashing the site.

Had to convert to a regular string-based prop.

React Context doesn’t work for components in Astro pages

Lets say you have a about.astro page. You also have a <PageLayout> React component that wraps all the page content, and it has a few context providers inside (theme, shared app state, etc). You write your page markup in the about.astro file — cause why not?

<DefaultPage>
  {" "}
  // Has context providers
  <AnotherReactComponent>
    {" "}
    // Doesn't have access to context - despite being nested
    <h1>About Page</h1>
    <MoreReactStuff /> // Also can't access context
  </AnotherReactComponent>
</DefaultPage>

All the nested React components inside the Astro file will not get access to the context.

The solution? Create your page entirely inside React, then import that whole page component into your Astro page.

In my case however, this didn’t work. I had react-three-fiber components that needed a special client:load tag in Astro to load them. And when I added that tag to the entire page component, the page rendered — but the R3F component didn’t.

My workaround? I ended up using zustand to create a store outside of “React-land” and using that between components. But this still was a major issue with a lot of wrapper components that needed access to context (like a theme provider).

Same with React `children`

I had issues using children when it was content from an Astro page and the React component was client:load:

<SomeComponent client:load>
    <h1>Content inside Astro file</h1> // SomeComponent can't load this

This has to do with the way they isolate code into “islands”. If you inspect the HTML, you’ll see that the component we labeled with client:load is in an isolated island, but the HTML template it uses doesn’t included the nested children content.

Utility Props Problem

A lot of my components are “dynamic” where they have Vanilla Extract’s Sprinkles API working to swap out classnames based on the props I pass to the component. For Astro, it’d initially render these components, but they’d lose their “interactivity” without a client:load directive. So I couldn’t see style changes when I swapped props.

This got a little tedious, since a lot of components use or extend from a component that uses utility props.

A little slow and clunky

I have archive pages that need to query all of my blog posts — every single one. This ends up being an intensive process, taking a few minutes for it to spin up a page (~75 blog posts). This doesn’t get cached between pages, so it re-runs.

It’s smart enough to cache if I update other code, but the cache actually works against you? Sometimes it’ll cache broken code, and I’m forced to delete massive chunks to trigger a proper reload. It causes a lot of false positives when coding, which can be frustrating when debugging complex (or even trivial) issues.

What makes it worse is there’s no built in cache clearing option? I think they’d benefit from an astro clean command to give you a clean slate sometimes.

Markdown images broken?

One thing I didn’t notice until the website was built and in production on Netlify — all my markdown images were broken. Which was weird, because they worked fine in development.

I literally went back and double checked and the development server was using:

https://whoisryosuke.com/blog/2022/2022-05-17_182533_-_Windows_PowerShell_Setup.png

While the production server used:

https://whoisryosuke.com/blog/2022/leveling-up-windows-powershell-with-oh-my-posh/2022-05-17_182533_-_Windows_PowerShell_Setup.png

I’m not sure what causes the difference between what the markdown parser shows in development vs production. Luckily though, because I was already migrating my content from my previous Gatsby blog, all I had to do was go back and change my migration script to use the production URLs.

Speaking of which, here’s what that migration script looked like. It goes through all my blog folders, edits Markdown to add the Astro layout, and copies images over to a separate folder (to copy into /public):

const fs = require("fs");
const path = require("path");

// Loop through all years
// Go into each folder

// Get MDX file
// Add template to frontmatter
// layout: "@/layouts/BlogLayout.astro"

// Found images in folder with MDX?
// Copy images to public/blog/YEAR folder

const ROOT = "./content/blog/";
const IMAGE_ROOT = "./images/";

const years = fs.readdirSync(path.join(ROOT));

years.forEach((year) => {
  const blogPostFolders = fs.readdirSync(path.join(ROOT, year));

  // Go into each folder
  blogPostFolders.forEach((blogPostFolder) => {
    const blogImagePath = path.join(IMAGE_ROOT, year);
    const blogPostFolderContents = fs.readdirSync(
      path.join(ROOT, year, blogPostFolder)
    );

    // Create folder if it doesn't exist
    if (!fs.existsSync(blogImagePath)) {
      fs.mkdirSync(blogImagePath);
    }

    blogPostFolderContents.forEach((file) => {
      const filePath = path.join(ROOT, year, blogPostFolder, file);
      const copyPath = path.join(IMAGE_ROOT, year, file);
      // Get MDX file
      // Add template to frontmatter
      // layout: "@/layouts/BlogLayout.astro"
      if (file.includes(".md")) {
        const blogPostMdx = fs.readFileSync(filePath, "utf-8");
        console.log("mdx", blogPostMdx);

        // Find frontmatter closing tag (second `---`)
        const splitPost = blogPostMdx.split("---");
        console.log();
        splitPost[1] = `${splitPost[1]}
layout: "@/layouts/BlogLayout.astro"
`;
        const joinPost = splitPost.join("---");

        // Save post
        fs.writeFileSync(filePath, joinPost);
      }

      if (
        file.includes(".png") ||
        file.includes(".jpg") ||
        file.includes(".jpeg") ||
        file.includes(".gif") ||
        file.includes(".svg")
      ) {
        fs.copyFileSync(filePath, copyPath);
        fs.rmSync(filePath);
      }
    });
  });
});

That fixed it, but now when I look at the site in development, none of my blog images work 😓 I can probably create a plugin to fix it in development, but I feel like this is a bug that’ll get resolved down the line.

Would I use Astro again?

Maybe. Probably not though. If I had a project that needed to merge multiple frontend frameworks, this would be a great pick. If I had a simple website that didn’t use too many dynamic elements, you’d avoid many of the headaches I had.

I also like the island architecture, despite being at odds with it in this project and framework. I think if Astro could support it in a more clear way that didn’t require the user to read docs and run into walls.

But if I had to create a Markdown based site, I’d definitely pick another solution (or wait until these bugs get worked out — cause it is easy to use compared to other frameworks).

The whole experience honestly had me appreciating NextJS a bit. It was missing a few things that Astro had (like easy MDX imports and frontmatter support), but the minimalism and freedom NextJS provided make it more attractive for prototyping and even production projects.

Grain of new salt

As someone who’s very new to the framework and didn’t bother to ask around on the Discord before complaining in this blog posts, this is just sharing my initial experience and critiques. Like I mentioned before, many of these issues will be resolved in the (often near) future. And I have no excuse to contribute cause it’s open source 😅

Are you using Astro in your project and enjoying it? Did I get something wrong about Astro? Let me know on Twitter. Always interested in hearing other’s experiences.

So when’s the redesign?

Soon.

And expect wild things like gamepad input 🎮

I’ve said too much already 😉

See you next time!
Ryo

References

Three.js no shadows on ShaderMaterial

A basic example of a ThreeJS (r108) ShaderMaterial with shadows, fog and dithering support.

How to add shadows to custom shaders using ShaderMaterial as basis
Basically need to include a bunch of scripts ThreeJS uses in other materials (like MeshLambertMaterial).
This is similar to the THREE.ShaderChunk["common"] process in older/vanilla stackoverflows

https://github.com/zadvorsky/three.bas/issues/7

Was finally able to import shader “chunks” (aka #include scripts from ThreeJS) — but was getting error about transformedNormal not existing. Had to define it myself.

react-three-fiber by example

Three.js Shaders Tutorial (part 2/2) | GLSL Shaders with Uniforms and Varying

DEV Community

Migrating my Gatsby MDX blog to AstroJS (and why you shouldn't)

The Process

Gatsby to Astro

Figma Design

Vanilla Extract with Sprinkles please

Time to surf 3D waves

Custom shadow shader

Light vs Dark mode

Hover interaction

Astro, blast off!

Astro-nomical Issues

Vanilla extract support

MDX Provider not supported out of box

Can’t use render props inside `.astro` files

React Context doesn’t work for components in Astro pages

Same with React `children`

Utility Props Problem

A little slow and clunky

Markdown images broken?

Would I use Astro again?

Grain of new salt

So when’s the redesign?

References

Top comments (0)

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The Process

Gatsby to Astro

Figma Design

Vanilla Extract with Sprinkles please

Time to surf 3D waves

Custom shadow shader

Light vs Dark mode

Hover interaction

Astro, blast off!

Astro-nomical Issues

Vanilla extract support

MDX Provider not supported out of box

Can’t use render props inside .astro files

React Context doesn’t work for components in Astro pages

Same with React children

Utility Props Problem

A little slow and clunky

Markdown images broken?

Would I use Astro again?

Grain of new salt

So when’s the redesign?

References

Read next

7 Best Java IDEs for Developers

/llms.txt: A Simple Way to Control How AI Bots See Your Site 🤖

Build Your Developer Portfolio: Exciting Web Development Projects You Can Start Today

🔥10 Useful Tools That Will Make Development Easier in 2025

Can’t use render props inside `.astro` files

Same with React `children`