Sandbox and Execution Budgets

Each computer owns one Lua VM. Every node instance receives an isolated environment and state map. Compiled prototypes are globally cached by API version and SHA-256 source hash.

Available libraries are base primitives, math, string, table, bit32, and coroutine. The runtime does not expose io, os, debug, package, require, load, loadfile, dofile, or luajava. Java reflection and arbitrary Java objects are unreachable.

File access is available only through the computed:fs endpoint. Every computer owns an isolated directory tree under the world save (<world>/computed/computer/<id>/); one computer can never see another computer's files. Each computer filesystem has a 1 MiB quota (get_free_space reports the remainder). Previews never touch the filesystem.

Each node invocation is limited to 50,000 Lua instructions. Each computer is limited to 500,000 Lua instructions per game tick. The private hook cannot be read or replaced by Lua. Limit errors abort the offending invocation, retain committed values, add an inline runtime diagnostic, and permit a later policy-driven retry.

Unloading a computer or replacing/removing a definition cancels its yielded coroutines.