Catching up on the Bluesky world, I missed this note in Last Week in Bluesky about trending topics:

The technological underpinning of how Trending Topics work on Bluesky is noteworthy: every trending topic is a custom feed. Every time a new topic is trending, a new custom feed gets created, giving the team better control over the topic. It also allows for new possibilities that have not yet been explored, such as archiving and documenting feeds after the trend is over, or other options that have not yet been explored.

I like it. Technical choices affect what’s possible with moderation.