# @babel/plugin-proposal-private-property-in-object > This plugin transforms checks for a private property in an object See our website [@babel/plugin-proposal-private-property-in-object](https://babeljs.io/docs/en/babel-plugin-proposal-private-property-in-object) for more information. ## Install Using npm: ```sh npm install --save-dev @babel/plugin-proposal-private-property-in-object ``` or using yarn: ```sh yarn add @babel/plugin-proposal-private-property-in-object --dev ```