Actor Declarations
Actors are the canister-facing services in Sector9. They encapsulate stable canister state, expose shared public methods, and define the boundaries where actor invariants, entry guards, and async interleaving matter.
Actor Fields
Actor fields store canister state across method calls. In a persistent actor, ordinary fields also participate in upgrade persistence, while transient fields reset on upgrade. Mutable fields are the main heap roots the verifier tracks with reads, modifies, permissions, and actor invariants.
Public and Private Members
Visibility modifiers control which functions can be called from outside an actor and where verification places actor-invariant boundaries.