René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"ng serve with esbuild/Vite ignores sourceMap configuration, injecting large inline source maps into all files","articleBody":"### Command\n\nserve\n\n### Is this a regression?\n\n- [ ] Yes, this behavior used to work in the previous version\n\n### The previous version in which this bug was not present was\n\n_No response_\n\n### Description\n\nThe development server (ng serve), which uses Vite/esbuild, consistently injects large, inline Base64 source maps into every JavaScript file it serves.\n\nThis behavior occurs even when source maps are explicitly disabled in angular.json and/or tsconfig.json. The most problematic aspect is that this transformation is also applied to pre-built, third-party packages from node_modules.\n\nThis unnecessarily inflates file sizes (often by 2-3x), which slows down page loads in development and makes debugging in browser DevTools more difficult due to the massive file content. The core issue is that the configuration to disable this behavior is not being respected. \n\n### Minimal Reproduction\n\n1.  Create a new Angular project:\n    ```bash\n    ng new sourcemap-repro\n    cd sourcemap-repro\n    ```\n2.  In `angular.json`, modify the configuration for the development server to explicitly disable all source maps. Under `projects.sourcemap-repro.architect.build.configurations.development`, set the `sourceMap` option:\n    ```json\n    \"sourceMap\": false\n    ```\n    *(Alternatively, using a more granular object like `{\"scripts\": false, \"styles\": false, \"vendor\": false}` also fails to prevent the issue.)*\n\n3.  Run the development server:\n    ```bash\n    ng serve\n    ```\n4.  Open the application in a browser and launch the developer tools (e.g., Chrome DevTools).\n5.  Navigate to the \"Network\" tab, refresh the page, and inspect any `.js` file (e.g., `main.js`, `polyfills.js`, or a chunk from `@angular/core`).\n6.  View the \"Response\" or \"Source\" for that file.\n\n**Expected Behavior:**\nThe served JavaScript files should **not** contain an inline source map. The file should end without a `//# sourceMappingURL=...` comment.\n\n**Actual Behavior:**\nEvery JavaScript file has a large inline Base64 source map appended to it, directly contradicting the configuration in `angular.json`.\n\n\n\n### Exception or Error\n\n```text\n\n```\n\n### Your Environment\n\n```text\nAngular CLI: 19.2.14\nNode: 20.19.0\nPackage Manager: npm 10.8.2\nOS: darwin arm64\n\nAngular: undefined\n...\n\nPackage                         Version\n---------------------------------------------------------\n@angular-devkit/architect       0.1902.15\n@angular-devkit/build-angular   19.2.14\n@angular-devkit/core            19.2.14\n@angular-devkit/schematics      19.2.14\n@angular/cli                    19.2.14\n@angular/compiler               19.2.14\n@angular/compiler-cli           19.2.14\n@angular/language-service       19.2.14\n@schematics/angular             18.2.11\nng-packagr                      18.2.1\ntypescript                      5.7.2\nzone.js                         0.15.0\n```\n\n### Anything else relevant?\n\n\u003cimg width=\"793\" height=\"356\" alt=\"Image\" src=\"https://github.com/user-attachments/assets/22cd3964-aa0d-432a-987a-eb50664007de\" /\u003e","author":{"url":"https://github.com/AlonMiz","@type":"Person","name":"AlonMiz"},"datePublished":"2025-09-28T14:33:40.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":0},"url":"https://github.com/31331/angular-cli/issues/31331"}