This reduces the compile time significantly. It is also a recommended
compiler option.

Note: Explicit usage of third-party code is still checked.

Since ts-node does not support project references we use js files with jsdoc type annotations instead.

This is needed to properly handle project references.

The increase is caused by a newer version of semver which introduced
memoization to improve the performance of range parsing. With this
lru-cache was added as a dependency which unfortunately leads to the
larger overall size of @feature-hub/core.

There is currently no issue without `skipLibCheck`, until we decide to
update to webpack 5, and
DefinitelyTyped/DefinitelyTyped#50773 is not
resolved till then.