Jest's configuration can be defined in the `package.json` file of your project, or through a `jest.config.js`, or `jest.config.ts` file or through the `--config <path/to/file.js|ts|cjs|mjs|json>` option. If you'd like to use your `package.json` to store Jest's config, the `"jest"` key should be used on the top level so Jest will know how to find your settings: