There's a caution story here. Today we finally pushed a near-complete rewrite in Angular of our Sproutcore app. It wasn't cheap.

When we started with SC, it was backed by Apple, Yehuda had just declared it the future of web development, and everything was very rosy.

After Ember split off from SC and the company developing it (Strobe) got acquihired by Facebook, the community got completely decimated and it quickly became a sinking ship.

The one thing SC never had was a ton of large scale real-world deployment (outside of Apple). I think that's the lesson here.