# @babel/plugin-proposal-private-property-in-object > ⚠️ This version of the package (`v7.21.0-placeholder-for-preset-env.1`) is not meant to > be imported. Use any other version of this plugin or, even better, the > [@babel/plugin-transform-private-property-in-object](https://babeljs.io/docs/en/babel-plugin-transform-private-property-in-object) package. > 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 ```