As others have said, the convention is to use tsc for typechecking and declaration file generation and babel (ie by way of webpack) for bundling. You should no

As others have said, the convention is to use tsc for typechecking and declaration file generation and babel (ie by way of webpack) for bundling. You should not have typescript mismatch issues if you follow good practices. You should get no mismatch with babel using one typescript version and your tsc command using another. Do not use a global tsc command for instance, typescript belongs as a dev dependency in your project