You can upload Z-Machine, Glulx, TADS 2 and 3, Hugo, Dialog, Texture and Ink game files as well as single-page HTML files which includes Twine and other formats that export to HTML. It sets up an online interpreter and you then get a shareable link that leads to a page to play the game online.
Uploaded games can be set public, which makes them appear on the public gallery on the front page, or private, which gives you just the link. The game can be played by following the link but private games aren’t listed on the front page or anywhere else on the site.
You need to log in with a Google account to upload games. No account is needed for playing.
The service is produced in cooperation with IFTF and it’s meant as a lightweight alternative to Itch.io and a replacement for the old philome.la site that hosted Twine games but has now been read-only for a couple of years.
Have fun and let me know if you have any questions.