This reminds me of Meteor.js[0] from back in the day (2014?), which had a very similar approach—you wrote code that ran on both the frontend and the backend, and database updates were propagated automatically. It suffered from a pretty hard reliance on Mongodb and its own package manager (Atmosphere), and it was at odds with the rest of the JS ecosystem which was settling on NPM.
This project looks very cool! I like the focus on composition, Meteor was lacking that (and really, most other frameworks do as well).