Configuring Custom Vite Settings in Angular 17

Angular 17 has introduced new changes and enhancements in its build system, including better integration with modern build tools like Vite. However, configuring Vite specific settings such as optimizeDeps directly through a vite.config.js file in an Angular project might not be straightforward due to the tightly coupled nature of Angular’s build system. In this blog post, we’ll explore how to effectively manage custom Vite settings in Angular 17, focusing on an issue related to dependency optimization.

Understanding the Challenge

Angular 17 still primarily uses its CLI for managing build processes, which means direct configuration of Vite through a vite.config.js might not be recognized as expected. Users trying to directly modify Vite settings may run into issues such as modules not being fetched dynamically due to non-optimized dependencies. This can lead to runtime errors like:

TypeError: Failed to fetch dynamically imported module

This error typically indicates that some dependencies aren’t being correctly handled by Vite’s optimization process.

Workaround for Configuring Vite in Angular 17

Since directly editing a vite.config.js doesn’t integrate seamlessly with Angular’s build process as of now, we need to consider alternative approaches. One effective method involves tweaking the Angular build process to disable certain new optimizations or caching mechanisms that might conflict with Vite’s default behavior.

Step 1: Modify Angular Build Configuration

To prevent Angular CLI’s new caching mechanism from potentially interfering with Vite’s module resolution, you can disable it in the angular.json file:

{
  "cli": {
    "cache": {
      "enabled": false
    }
  }
}

Disabling the CLI cache helps ensure that the build process does not store outdated dependencies or modules that could conflict with Vite’s optimization strategies.

Step 2: Implementing a Proxy Configuration

Since direct Vite configuration isn’t recognized, another approach is to implement a workaround using a proxy configuration script that can mimic some of Vite’s intended behaviors within Angular’s ecosystem. For example, to exclude certain packages from the optimization process, you could use a custom script that adjusts the build process:

// proxy-config.js
module.exports = function (config) {
  config.optimization.runtimeChunk = false;
  config.optimization.splitChunks = {
    cacheGroups: {
      default: false,
      vendors: false,
      // Exclude specific dependencies from chunks
      'my-third-party-package': {
        test: /[\\/]node_modules[\\/]my-third-party-package[\\/]/,
        name: 'my-third-party-package',
        chunks: 'all',
        enforce: true,
        reuseExistingChunk: true
      }
    }
  };
  return config;
};

Step 3: Integrate the Proxy Configuration

After setting up your proxy configuration, integrate it into your build process by modifying the angular.json to use this custom script during the build:

{
  "projects": {
    "your-project-name": {
      "architect": {
        "build": {
          "options": {
            "customWebpackConfig": {
              "path": "./proxy-config.js"
            }
          }
        }
      }
    }
  }
}

While Angular 17 doesn’t currently offer native support for direct Vite configuration through a vite.config.js file, there are workarounds that can approximate the desired behavior. By adjusting Angular’s build process through a custom proxy configuration or disabling certain new optimizations, developers can tailor the build process to better fit their needs, including managing how dependencies are optimized. As Angular continues to evolve, it’s likely that future releases will offer more integrated and flexible ways to configure underlying build tools like Vite directly.