It can be useful to import a module for a single session without saving it as a scratchpad, or to be able to use it against a webpage.

Browsers support top-level await and ESM URL import, which are the keys to this. JSPM is a CDN that allows you to import any library as an ESM.

Suppose you want to import the latest version of request.

var request = await import('')

You can then extract the core request as request.default. You can import a particular version by changing the url – e.g. for 2.27.0.

You can also import ESMs from other CDNs, such as Skypack.

This isn’t yet possible in Node (14) – while ESMs are supported with the --experimental-modules flag, they can only be imported if already saved or as data URIs, not by URLs. Top-level await is supported with the --experimental-repl-await flag.