Any framework that allows me to write simple code which then gets _automatically_ highly optimized to run efficiently and with high/low priority based on the us

Any framework that allows me to write simple code which then gets _automatically_ highly optimized to run efficiently and with high/low priority based on the user-interaction and effectively removes race-conditions and makes it more intuitive to deal with loading states is a good thing for me. In fact this feels so advanced stuff (React's runtime I mean) that it will probably one day land in the browser. So React's team is just one step ahead of the others, they are thinking: "what's the least amount of code we can let developers write so that we can optimize away all the rest of the stuff?". One thing I'm worried is whether with all these amazing optimizations and very different code-execution model, we have to rethink some of the valuable simple lessons of software architecture we learned over the years. For instance, we have to rethink a bit about how to organize code and how to test it. Some things that before we could confidently say "this piece of code will run at this time" will now be a bit more like "not sure when this piece of code will run". Cool stuff, but some tradeoffs to consider.