benilla-lua is a Lua 5.1.5 interpreter in Rust that speaks the 1.12.1 client's grammar. It is opt-in behind the `benilla-vm` feature, with `benilla-mlua`, the slice of mlua that benilla-ui uses, over it. The C build stays the default. Its front end ports 5.1.5's `lparser.c` and `lcode.c`, so registers, limits and messages match the C build's.
Our finish on top:
- the collector counts growth as C does, off the write path;
- frames under a leaky generic `for` start nil, as `luaD_precall`;
- the budget hook counts what C dispatches, and costs nothing when unset;
- `__index` chains stop at 100;
- mlua 0.11's conversions;
- `vm_parity` answers recorded per platform.
Tests: `vm_parity` on both VMs; the front-end corpus (8,543 chunks) against `string.dump`; 7,613 app and UI tests on benilla-lua. Built on macOS; Linux by CI.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Co-Authored-By: Sam <samuv.eth@gmail.com>
Mathih13