Right now you can embed the gist by % followed by [] having the link to your gist, which includes all the files from that gist.

If you want to only add some files from that gist, you have to do it by adding ?file=index.js to the link. That seems to not work in hashnode, as the API response automatically adds .js at the end of generated URL in script tag

e.g.

This is snippet from my draft article

Response from first embed

Response from second embed