[twic]

> However a special ID of “$” means: assume I’ve all the elements that there are in the stream right now, so give me just starting from the next element arriving.

I can already see lazy users just repeatedly reading $, and then dropping messages when they arrive faster than they read them.

Might it be safer to instead have command to ask what the latest ID in the stream is? You'd start off by using that to work out where the streams are, then construct an XREAD command to read from there. To construct your next XREAD, it should be easier to update the IDs from the ones you just read, rather than fetching the latest IDs again. Maybe.