From this twitter thread: https://twitter.com/nullvoxpopuli/status/1673077290593554434 The solid.js implementation augments the `state` from the interpreter instance https://github.com/statelyai/xstate/blob/740409e549ea91974b7fa8ef63438341958dafd9/packages/xstate-solid/src/useMachine.ts#L38C29-L38C44 via this `createImmutable`. Note that the concept of `createImmutable` should exist as a `util` in ember-resources https://github.com/NullVoxPopuli/ember-resources/