Laravel mix Uncaught ReferenceError: jQuery is not defined

Stefan Bogdanescu

Founder & Senior Architect · 2026-06-29

Laravel Company

Mastering JavaScript Dependencies in Laravel Mix: Solving the dreaded "jQuery is not defined" error

As developers working within the Laravel ecosystem, we often leverage tools like Laravel Mix (or Vite) to bundle our frontend assets. This process streamlines development by combining multiple JavaScript files into optimized bundles. However, when dealing with external libraries like jQuery or Bootstrap, managing their dependencies and ensuring they are correctly loaded in the browser environment can introduce subtle but frustrating runtime errors, such as Uncaught ReferenceError: jQuery is not defined.

This post dives deep into why this happens and provides a comprehensive strategy for managing JavaScript dependencies effectively, whether you are bundling assets or loading scripts directly in your Blade views.

The Root Cause: Bundling vs. Runtime Loading

The error you are encountering stems from a mismatch between how your compiled assets are loaded and when the global variables are actually defined in the browser's scope.

When you use import "jquery"; in a modern module setup (like in Webpack), you are telling the bundler to include jQuery, but this only affects the JavaScript files that are compiled by Mix. If you then try to load a separate script directly into your Blade view—especially within sections or inline <script> tags—that external script does not inherit the dependency context established by the Webpack build process.

The webpack.ProvidePlugin configuration successfully injects jQuery as a global variable ($) into the bundled output, which is why it works in compiled files but fails when raw scripts are executed in isolation within the HTML structure.

Strategy 1: Centralizing Dependencies via Bundles (The Correct Way)

For any code that relies heavily on external libraries and needs to be optimized, bundling is the superior approach. You correctly identified the need for dependency injection during the build process.

Here is how you ensure your bundled assets are self-sufficient:

// webpack.config.js snippet
mix.webpackConfig(webpack => {
    return {
        plugins: [
            new webpack.ProvidePlugin({
                $: 'jquery',
                jQuery: 'jquery',
                'window.jQuery': 'jquery',
            })
        ]
    };
});

This configuration ensures that any module inside your bundle can access $. This is critical when you rely on Mix to handle the final delivery of assets, as recommended by best practices in modern asset management. For robust framework development, understanding these build-time configurations is key to maintaining clean code structures, much like adhering to principles found in high-quality Laravel development.

Strategy 2: Managing Raw Scripts in Blade Views

The challenge arises when you mix bundled files (vendor.js, app.js) with raw scripts placed directly in the view layer, such as within @section('scripts').

To resolve the $ is not defined error for these inline scripts, you must ensure that jQuery is loaded before any script attempts to use it. Since Laravel Blade renders HTML sequentially, controlling the order of asset loading is paramount.

The Recommended Approach: Global Loading Order

Instead of relying on implicit module imports in your view, treat all external dependencies as global requirements that must be loaded explicitly before execution.

If you are loading scripts via mix(), ensure they reference each other correctly and load in a defined sequence within your main layout file.

Example of Correct Script Ordering:

Ensure your master layout loads the core dependencies first:

<body>
    @yield('body')

    {{-- 1. Load Core Dependencies (jQuery, Bootstrap) First --}}
    <script src="{{ mix('/assets/vendor.js') }}"></script>
    <script src="{{ mix('/assets/bootstrap.js') }}"></script>

    {{-- 2. Load Application Logic Last --}}
    <script src="{{ mix('/assets/app.js') }}"></script>

    @section('scripts')
        {{-- Now, any script here can safely assume jQuery exists globally --}}
        <script type="application/javascript">
            window.onload = function() {
                // This check is now reliable because the dependencies are loaded above
                if (window.jQuery) {
                    console.log("jQuery and Bootstrap are successfully loaded.");
                } else {
                    console.error("Error: Dependencies failed to load.");
                }
            }

            // Example usage after loading:
            $(document).ready(function () {
                console.log('DOM is ready and jQuery is available!');
            });
        </script>
    @endsection

    @yield('footer')
</body>

By explicitly loading the vendor files (which contain the injected dependencies) before your application logic, you establish a reliable global scope for all subsequent scripts in that view. This approach ensures consistency and predictability, which is vital when building scalable applications with Laravel.

Conclusion

The conflict between bundled module imports and raw script execution highlights a fundamental principle of front-end development: context matters. While Webpack/Mix excels at compiling dependencies into optimized bundles, runtime errors often occur when the browser environment lacks those dependencies before the code attempts to execute.

The solution is not just about configuring your build tool; it's about disciplined asset loading in your Blade templates. By centralizing dependency loading and ensuring a strict execution order, you can eliminate these frustrating reference errors and build more stable, maintainable applications on top of Laravel.