There's many ways to do this, but at its simplest because Node is single threaded, you can have a shared array of URL's and then a pool of workers who .pop() a

There's many ways to do this, but at its simplest because Node is single threaded, you can have a shared array of URL's and then a pool of workers who .pop() a URL off and stop when there are none left. Each worker's http request runs async, so with the `async` keyword at the start of their signature, and `await fetch(url)` inside, the code reads (and in some ways behaves) like regular synchronous iteration but runs (mostly) concurrently.