Problem Statement
Why does Flutter have good performance compared to other cross-platform frameworks?
Explanation
Flutter achieves excellent performance by compiling directly to native ARM machine code using AOT compilation, eliminating interpretation overhead and JavaScript bridges that slow down other frameworks. The compiled code runs at native speed without any intermediate layers, and Flutter's rendering engine (Skia) draws directly to the canvas without going through platform widgets.
Flutter's architecture avoids the performance bottlenecks of bridge-based frameworks where every UI update must pass through a JavaScript bridge to native code. By rendering everything itself, Flutter eliminates this bridge entirely, allowing widgets to communicate directly with the rendering engine. This is why Flutter can maintain 60fps or even 120fps on capable devices even with complex animations.
The framework uses intelligent algorithms for diffing and reconciling widget trees, reusing existing RenderObjects when possible to minimize expensive layout and paint operations. Widgets being lightweight immutable objects means rebuilding them is cheap, while the heavier RenderObjects are reused across rebuilds. Flutter also leverages GPU acceleration for compositing layers and rendering.
Additionally, Dart's memory management is optimized for Flutter's pattern of creating and destroying short-lived objects, with generational garbage collection minimizing pauses. The ability to use isolates for CPU-intensive work without blocking the UI thread further improves perceived performance. These architectural decisions make Flutter one of the best-performing cross-platform frameworks available.
