This seems to be a common misconception. TypeScript can be added gradually as well with strict settings disabled, and supports JavaScript with a config setting

This seems to be a common misconception. TypeScript can be added gradually as well with strict settings disabled, and supports JavaScript with a config setting. With Babel now supporting TypeScript[1], none of these arguments prevail. [1]: https://www.npmjs.com/package/babel-preset-typescript https://www.npmjs.com/package/babel-preset-typescript