flutter run --profile  # Required for profiling
flutter pub global run devtools

// GOOD
const Column(children: [Text('Static'), Icon(Icons.star)])

// GOOD: Only counter rebuilds
Column(
  children: [
    const ExpensiveWidget(),  // no rebuild
    _Counter(),               // isolated state
  ],
)

RepaintBoundary(child: AnimatedWidget())

// BAD: compute in build
final sorted = items..sort();

// GOOD: compute once
late List<Item> _sorted;
void initState() { _sorted = items..sort(); }

@override
void dispose() {
  _animController.dispose();
  _textController.dispose();
  _subscription?.cancel();
  super.dispose();
}

// Check mounted
if (!mounted) return;
setState(() => _data = data);

// Use builder
ListView.builder(itemCount: items.length, itemBuilder: ...)

// Fixed extent
ListView.builder(itemExtent: 72, ...)

// Keys
ValueKey(item.id)

CachedNetworkImage(
  imageUrl: url,
  memCacheWidth: 200,
  memCacheHeight: 200,
)