# Caller post-back uses getSelf io_context

Viral posting invokers resume the caller on the thread that issued `co_await`, using `callerIoContext` captured from `ComponentThread::getSelf()` at promise construction time.

Dynamic `ExplicitPostTarget` only affects post-TO (`initial_suspend`), not post-back.

See [post-to-and-back-in-invokables.md](post-to-and-back-in-invokables.md).