default_ property
Default is true when no pipeline is stored for this project and these are the built-in world feeds. Writing one turns it false.
Please note: This property should have been non-nullable! Since the specification file does not include a default value (using the "default:" property), however, the generated source code must fall back to having a nullable type. Consider adding a "default:" property in the specification file to hide this note.
Implementation
bool? default_;