I Replaced Arrays of Objects with One ArrayBuffer - React Native Became 200x Faster

Most JSI benchmarks are misleading. They benchmark the native call itself, but not the actual cost of moving data into JavaScript. In real React Native applications, the bottleneck is often not JSI itself. It’s the shape of the data crossing the boundary. Returning thousands of JavaScript objects from native code creates allocations, property definitions, boxing, hidden classes, and garbage collection pressure. Even with JSI removing the traditional bridge, large payloads can still become su...