If you're using BubbleIQ for IT or B2B customer support in Slack, your customers are able to respond to tickets directly from threads in Slack. It makes sense that they would be able to receive and reply to CSAT surveys in Slack, too.
Turn this feature on by messaging the BubbleIQ bot admin and clicking "Setup CSAT"
Now, when a ticket gets closed, the requestor of the ticket will receive this message in Slack:
When they open up the survey, they can give you a thumbs up, thumbs down, and comments.