[disclaimer: I work on the Dart VM] Dart is actually not statically typed: in production mode (which is default) type annotations are ignored completely, in ch

[disclaimer: I work on the Dart VM] Dart is actually not statically typed: in production mode (which is default) type annotations are ignored completely, in checked mode they are translated to runtime type guards and not checked globally&statically during compilation. For more details please take a look at: http://www.dartlang.org/articles/why-dart-types/ http://www.dartlang.org/articles/why-dart-types/ Published benchmark scores are coming from the production mode. Even if you remove all type annotations performance will not change a bit. In fact by design Dart VM does not use any information provided in type annotations to perform optimizations.