error: Could not find a declaration file for module ‘@ckeditor/ckeditor5-build-classic’ angular 9
Add typings.d.ts file in your project root or any folder add following code into the typing file declare module ‘@ckeditor/ckeditor5-build-classic’ { const ClassicEditorBuild: any; export = ClassicEditorBuild; } that’s it angular will automatically detect typings and compile it as dependency this will solve the issue its also sugggested in official CKEDITOR page: https://ckeditor.com/docs/ckeditor5/latest/builds/guides/integration/frameworks/angular.html Directory Structure