It means instead of the philosophy prevalent in the JS world of bringing everything in as a dependency by yourself, the library attempts to provide sensible default solutions for you.

I don’t know what that might cover, but it might be things as basic as parsers for headers and cookies. Which I applaud, because me personally, that’s shit I’ve never wanted to think about.

When it comes to frameworks (any framework) any jargon not explicitly pointing to numbers always eventually reduces down to some interpretation of easy.

It’s a slogan popularized by Python.

Python with its seven circles of infinite package hell also demonstrates the limits of this approach. It’s not very useful that the language gives you two AA batteries when your application needs a megawatt of power (metaphorically).

Batteries included really means large sections of the factory included!

Always the wrong sections in my experience...

If it includes third party middleware, is it still third party?