Five minutes or less, in English. Loom, YouTube (unlisted is fine), Vimeo, Drive, or Streamable, and the link must point at the video itself, not a folder. Make sure it is viewable by anyone. We want two things in it: your face on camera introducing yourself, and a screen recording walking through the best thing you have built, what was hard about it, and how people found it. Casual is fine, content matters far more than polish.
One difference from the video: it calls the screen recording optional. For this role it is not. Show us the thing you built.