Install jq and youtube-dl

Get a list of the last 100 URLs:

curl https://api.twitch.tv/kraken/channels/${TWITCH_USER}/videos?broadcasts=true&limit=100 | 
  jq -r '.videos[].url' > past_broadcasts.txt

Save them locally:

youtube-dl -a past_broadcasts.txt -o "%(upload_date)s.%(title)s.%(id)s.%(ext)s"

Did it. youtube-dl is smart enough to avoid re-downloading videos it already has, so as long as you run this often enough (I do daily), you should avoid losing videos before they’re deleted.

Thanks jrayhawk for the API info.