Which Dart language features matter most in Flutter work?

Dart is statically typed and null-safe. A nullable type must be handled before use, and the compiler enforces that at compile time. Flutter code also leans on final fields, const constructors and collection literals, because immutability makes widget rebuilds cheaper and reasoning easier.

String greet(String? name) {
  final display = name ?? 'guest';
  return 'Hello, ' + display;
}

void main() {
  final record = (name: 'Asha', age: 28);
  print(greet(record.name));

  final scores = <int>[42, 87, 65];
  final passed = scores.where((score) => score >= 70).toList();
  print(passed.length);
}

Features that appear constantly

• Null safety with ?, ??, ??= and the null-aware spread operator
• late for fields initialised after construction, such as controllers in initState
• Records and destructuring for returning multiple values without a class
• Pattern matching and sealed classes for exhaustive state handling
• Extension methods for adding behaviour without inheritance

Dart is single-threaded per isolate but supports asynchronous concurrency through Future and Stream. That model is why blocking work must move to an isolate rather than spawning a thread and sharing memory.