as per this git - https://github.com/angular/angular-cli/issues/8284 The reason for this rule is that the TypeScript version your app isn't necessarily the same as the TS version your library uses. Different versions of TS can produce different output, and give different errors for the same input. They don't even support the same language features. So packaging libraries with TS sources will always break someone's project. So we don't really support using incorrectly packaged libraries with TS sources. It's something you do at your risk. That being said, maybe you can try adding it to the include array. But I can't guarantee that will work in the future because it's still an incorrectly packaged library. this is a major issue especially for universal apps trying to use MDBootstrap. anything we can do about it?

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