I have a project that's behind corporate proxy. We used to use an internal Artifactory (X) - everything works. I can commit and push, the build agent picks it up, downloads npm packages, builds and publishes it. All good. Recently it was decided that Artifactory X will be retired and everyone will move to Artifactory Y. I went over to my .npmrc file and updated the artifactory settings to the new one, something like: email = my.email@company.com always-auth = true registry=https://y-artifactory.company.com/artifactory/new/url/ //y-artifactory.company.com/artifactory/new/url/:_authToken=here-goes-my-auth-token I got this from the "set me up" from the new Y Artifactory, the same way I had set up the old one. However, here, when I build the project either locally or via our build agent, I first get a missing package error - for @types/minimatch. According to some GitHub posts, I should never even add it, but I added it to my development packages and run, but now it throws an even weirder error: ERROR in ./node_modules/react-draggable/build/cjs/Draggable.js 210:22 Module parse failed: Unexpected token (210:22) You may need an appropriate loader to handle this file type, currently no loaders are configured to process this file. See https://webpack.js.org/concepts#loaders | // the underlying DOM node ourselves. See the README for more information. | findDOMNode() /: ?HTMLElement/{ > return this.props?.nodeRef?.current ?? _reactDom.default.findDOMNode(this); | } | render() /: ReactElement<any>/{ Angular/TypeScript is complaining about optional property chaining. I understand the error, and know why it usually happens, but in my case, I'm targeting ES2015. Here's my relevant config: "lib": ["es2015", "dom", "ES2020.String"], "target": "es2015", "experimentalDecorators": true, "lib": ["es2015", "dom", "ES2020.String"], "module": "esnext", "moduleResolution": "node", "target": "es2015", So I don't understand why I am getting this error. It should have been transpiled. Furthermore, this error is pointed at a third party library we use (we use both Angular and React in the same project). If I switch back to Artifactory X, everything just compiles well and runs okay. Literally no other changes but the Artifactory change and it fails. I can see that: I am authenticated successfully npm packages are downloaded successfully Build started successfully Build fails with either missing type definitions for minimatch, or when I explicitily add the package, it fails with optional prop chaining. What would make my Angular build fail when just an Artifactory change? Continue reading...