I was going to say that the API is almost identical to Snabbdom's and ask whether that was voluntary or an independent reinvention, but given how similar the "inline example" is[0][1] (down to the comments) I assume either snabbdom was used as a starting point or the inspiration is very much wilful?

[0] https://github.com/mbasso/asm-dom#inline-example

[1] https://github.com/snabbdom/snabbdom#inline-example