We can't be everything to everyone, not a blocker, but I do want to just raise the topic & see what comes out, Malloy seems purely to be a querying tool. So we'd probably have parallel Knex.js code to write data, then Malloy to read it? I should check your road map (yay you have a road map!) to see if there's anything far off here, but it was one of the major other thoughts I had about trying to get onto Malloy.
Hats off on the GitHub vscode notebook. Really really nice malleable tactile way to show the project off. It seems like there is a DuckDB (itself very promising new tech) instance that it relies on, which I think somehow the Malloy vscode extension provided & loads the data into automatically... Is this running on my browser, or GitHub? How? What's the magic that makes this happen? It was really cool seeing the markdown notebook be so tactile, a great feat; really well done!