The code and the slides for the lightning talk live coding I did on Wrocław TypeScript #7.
The slides for Kraków TypeScript User Group #5 are on the extended-15-minutes branch.
I've got some notes about refinement types in a gist blogpost.
There are links to some good stuff in the 5th slide.
You can find the notes I made to prepare for the talk in a Dropbox Paper doc.