# Lifetime, safety, and compatibility [Back to C++](https://rustic-game-engine.pages.dev/markdown/scripting/cpp.md). C++ cannot call another behavior process or VM object. API 1.0 does not yet expose the scheduler's Engine Event `emit`/`subscribe` surface to scripts; cross-language coordination must use shared engine state. Create and attach the file in the Explorer as global, scene, or component scope. The Asset ID—not the path—is stored in the attachment. Global instances run first, then scene instances, then object components; editor-created references use order `0` and stable IDs break ties. Process globals persist for that instance until it is destroyed. The process reads/writes newline-delimited protocol v1 internally. Do not print to standard output, because it is reserved for the SDK response. Callbacks have a three-second deadline and 1 MiB response limit. The process environment and working directory are isolated. Syntax/build failures prevent replacement; runtime failures disable the instance. Legacy C++ behavior members are the current native contract and remain backward compatible.