Using asyc/await vs promises makes very different design decisions in js and if you know only one you may not design something optimally Optimally? How would y

Using asyc/await vs promises makes very different design decisions in js and if you know only one you may not design something optimally Optimally? How would you even define that? Good developers make good use of the tools that are laid out before them, and sure the available tools differ in each language. But: 1. These languages tend to have more in common than they do different. 2. These concepts aren't magic. They're relatively easily understood, and you can make good use of them long before you can call yourself an expert in the language. 3. A good design doesn't necessarily make use of any specific language feature. e.g. a Go library might be well designed and make use of mutex (a very generic and ubiquitous concept). It's not a "quick hack" just because the author didn't choose to use channels.