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alexander-akait merged 5 commits into from
Apr 17, 2026
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docs: clarify webpack loader execution order (right-to-left) #8136

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docs: clarify webpack loader execution order (right-to-left)
mr-baraiya Mar 29, 2026
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docs: clarify loader execution order and update example
mr-baraiya Mar 30, 2026
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docs: clarify loader execution order and update example to use postcs…
mr-baraiya Apr 16, 2026
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docs: clarify loader execution order, update example, and improve exp…
mr-baraiya Apr 16, 2026
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docs: fix mdx syntax and update loader example structure
mr-baraiya Apr 16, 2026
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22 changes: 17 additions & 5 deletions src/content/guides/asset-management.mdx
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Expand Up @@ -13,6 +13,7 @@ contributors:
- astonizer
- snitin315
- Brennvo
- mr-baraiya
---

If you've been following the guides from the start, you will now have a small project that shows "Hello webpack". Now let's try to incorporate some other assets, like images, to see how they can be handled.
Expand Down Expand Up @@ -95,15 +96,26 @@ npm install --save-dev style-loader css-loader
};
```

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Copilot AI Apr 16, 2026

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This section shows test: /\.css$/i in the config diff, but the explanatory sentence about test being a regex that selects which files the rule applies to was removed. Consider reintroducing a short explanation (e.g., that this rule targets .css files) so the example is self-contained for readers unfamiliar with webpack’s module.rules format.

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In this rule, `test: /\.css$/i` is a regular expression that tells webpack to apply the rule to `.css` files.

Copilot uses AI. Check for mistakes.
Module loaders can be chained. Each loader in the chain applies transformations to the processed resource. A chain is executed in reverse order. The first loader passes its result (resource with applied transformations) to the next one, and so forth. Finally, webpack expects JavaScript to be returned by the last loader in the chain.
Module loaders can be chained. Each loader in the chain applies transformations to the processed resource. A chain is executed in reverse order (right to left).

The above order of loaders should be maintained: [`'style-loader'`](/loaders/style-loader) comes first and followed by [`'css-loader'`](/loaders/css-loader). If this convention is not followed, webpack is likely to throw errors.
For example, given the following rule:

T> webpack uses a regular expression to determine which files it should look for and serve to a specific loader. In this case, any file that ends with `.css` will be served to the `style-loader` and the `css-loader`.
```js
export default {
module: {
rules: [
{
test: /\.scss$/i,
use: ["postcss-loader", "sass-loader"],
},
],
},
};
```

This enables you to `import './style.css'` into the file that depends on that styling. Now, when that module is run, a `<style>` tag with the stringified css will be inserted into the `<head>` of your html file.
Even though `postcss-loader` appears before `sass-loader` in the `use` array, webpack runs `sass-loader` first (compiling Sass into CSS), then runs `postcss-loader` on the result.

Let's try it out by adding a new `style.css` file to our project and import it in our `index.js`:
If this order is not maintained, webpack may throw errors.

**project**

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