What Async Promised and What It Delivered

Article

TL;DR: Async/await solved callback hell but introduced function coloring, silent failures, and new deadlocks.

Key Takeaways

• Unhandled promise rejections created an entirely new silent failure class that callbacks didn’t have
• Go goroutines and Java Loom virtual threads avoid function coloring entirely by design
• Zig went furthest — removed async/await from the language altogether

Discussion

• [jasode]: Go and Java Loom explicitly chose no function coloring; Zig removed async entirely
• [paulddraper]: Java also has silent unhandled rejection failures identical to JavaScript’s
• [andrewstuart]: Async is hard to learn but massively rewarding once internalized
• Community agreed async/await traded one class of bugs for another; Go/Loom approach now looks prescient.

Discuss on HN