Aug 29, 2017 · 1 min read
Both.
DDC+Chrome is the new way to iterate quickly on web code; it replaces Dartium.
All Dart 2 runtimes will support the same semantics — they are the semantics of Dart 2, after all — so dart2js will get the new checks. But you’ll still need DDC for development, because dart2js will remain a whole-program compile.