Feels like knockoutjs, i recall using it 10 years ago. It was all so simple back then.
Yeah, actual components like you’d encounter with any modern framework/library like React.
It has some nuances but they are pretty much real components, and I was able to make some pretty advanced functionality in an otherwise typical spaghetti code disaster.
Even wrote unit tests for it. People were in disbelief any of this was even possible.
Turns out that while modern patterns and tooling go a long way, they you still need to put effort into making quality software of any kind.
Apparently, they even have a v4 reboot: https://www.tko.io/
Maybe my memory is that bad now in my old(er) age. But at that point in 2015, React had been a thing for about 2 years already. Ember had components even earlier than that in 2011/2012. Using components generally was a pretty well-accepted pattern from my recollection. The wars between the frameworks were all centered around render performance rather than APIs (i.e. which virtual DOM was best? do you even need a virtual DOM? etc.)
Not taking anything away from knockout per se, more just gut checking my own understanding/remembrance of that dark age.