- it has a bunch of useful serialization sugar (e.g. `{{ classes }}` serializes correctly whether it's an array, an object of booleans, etc. This is similar to Angular (in React-land, this got pulled out into a separate package, classnames). There's similar sugar for `style` and objects (which React also supports).
- I'm not a fan of the variadic event handler signature. If I understand correctly, having a event handler inside a loop adds an extra argument to the handler function, but what happens if there are nested loops? In React-land, this would be done w/ arrow functions and closures; in Angular, one would write a js function call similar to plain HTML event handlers. I prefer the React approach (though I understand that isn't really an option for the way you approached synergyjs)
- Similarly, if `#` is bound to loop index, then how do you access outer loop index in a nested loop situation?
- Binding view property names to form controls of the same name is an interesting abstraction. React looks clunky in comparison (yes, even hooks). Angular has a similar facility, with the addition of allowing custom transformation logic (think getter/setters for bidirectional bindings).
- prerendering via a browser-like environment isn't the best approach IMHO (I've seen people run into issues w/ jsdom missing features, for example, and something like puppeteer is a bit of a heavy thing to be running frequently server-side)
- I like the clear separation between JS and CSS (but, then again, I'm an old school person). React people might dislike it if they're used to css-in-js per-component style encapsulation.
Overall impression: appears to pack quite a punch for 4kb (more so than Preact IMHO, because of how it handles forms). Docs are clear and to the point, but could use more examples/tutorials (especially lifecycle hooks). Would like to see it mature a bit (e.g. in terms of addressing things like nested loops, as mentioned above), and I think it would benefit from considering a less expensive SSR approach.
Very promising!