Using @import 'file' imports from node_modules when the file is named the same way any node module is named.

Angular.json

"stylePreprocessorOptions": {
              "includePaths": [
                "src/styles"
              ]
            },

Existing files

src 
   - styles
          - _globals.scss
          - _rxjs.scss

my-component.scss

@import 'globals';

-> Imports node-module "globals" index.js

my-component.scss

@import 'rxjs';

-> Imports node-module "rxjs" index.js

Version
@angular/cli: 6.0.0-rc.7