You wake up in a dark room.
You don’t remember how you got there.
You are not alone.
Around you are many other people, all regaining consciousness at the same time.

Suddenly, a screen flickers to life. Someone screams.
A grainy figure appears.
It’s a puppet, with red swirls painted on its face.
The puppet is riding a tricycle.
Jigsaw.

“Hello, and welcome. I trust that you are wondering where you are. I can assure you that while your location is not important, what I offer for you is important: salvation. You’ve worked for years building applications and systems, but do you really understand your tools? Are you truly free to express your intentions? For your sake, I hope so.”

You look around you.
The dirty walls are covered with code.
“|”. “&”. “infer”. “extends”.

Advanced TypeScript…
Union Types. Conditional Types. Mapped Types. Template Literal Types.

“Around you is everything you need to save each other, and yourselves. But I’m not an unreasonable person. I’m willing to teach you. We have twenty minutes. Let’s play a game.”