Where is the right place to write packages for Laravel?

Question

Laravel

I want to write a small package for Laravel. Where is the best place to start writing? As I understand it, it must be written as part of the framework so that it is possible to write tests and inherit from the Laravel TestCase. Accordingly, there are 2 options left: vendora directory, which seems to me not a very good idea, or another place in the project.
Tell me, where are the development packages for Laravel usually stored?

Answer 1

Or store it separately from the project, then upload it to your project via composer.
Or create any folder (eg Library) in app and store it there.

Answer 2

More practical in /vendor folder IMHO