Very cool work! And great performance.
Funny - during quarantine I've been playing with the OPPOSITE. A no build, runtime only reactive JS engine...
Would love to compare notes - you can check out (very much WIP progress) at https://github.com/sreekotay/reefer
It's been only a few weeks of fun... but REALLY interesting problem space. I use a DOM memo-ish approach to help with performance...