Breaks

exceptions are no longer objects but Enums

Untyped generics for proc must be marked by {.untyped.} (otherwise the generics type will be forced to resolved and results in notype(no operations/proc binded))

varargs types are replaced by varargs pragma and unpack() iterator

Slightly breaks

var has to be explicitly initialized(v2: {.experimental: "strictDefs".})

concept is new style (implicit Self)

base methed no longer needs to be marked by {.base.}

Added

TYPE not nil (v2: {.experimental: "notnil".})

system.concat

system.allocFixed,etc

…