Lua runtime guide
Protecting MoonLoader and SA:MP Lua scripts
MoonLoader scripts run in a different environment from Roblox scripts. A protected file can be valid Lua and still fail when it reaches a game-specific API, LuaJIT FFI call or native hook. Test in the runtime you actually ship.
Check compatibility before a release
Start with a working source script. Obfuscate one representative build, then run it in the same MoonLoader and SA:MP setup your users have. Exercise startup, event handlers, FFI calls, memory access and shutdown. Compare the logs and behavior with the original. A clean parse alone is insufficient.
Keep the test small enough that you can tell what failed. Begin with startup and a simple event callback, then add the libraries and native calls your release actually uses. Record the loader and LuaJIT versions when you test; a result from a different setup is not a compatibility guarantee.
A useful test record has four columns: feature, original result, protected result, and the environment used. For a small squad utility, that might look like this:
| Feature | What to compare |
|---|---|
| Startup | Loaded modules, initialization order and first visible output. |
| SA:MP event callback | Arguments received, return values and whether the callback still fires after a reconnect. |
| FFI or memory read | Pointer type, address assumptions and behavior on the same game version. |
| Shutdown | Hooks removed, files closed and errors reported during unload. |
LuaJIT and FFI need special attention
Code using ffi.cast, native modules or host-provided functions depends on the surrounding runtime. An obfuscator should preserve calls and values, but it cannot supply missing modules or validate every game memory layout. Keep platform-specific integration tests for each update.
Check whether an FFI failure is environmental before blaming a compiler transform. Run the original and protected files with the same MoonLoader and LuaJIT installation. If both fail to load ffi or a native module, fix the installation or architecture mismatch first. If only the protected file fails, reduce the failing function to a small example and include the exact error and build identifier in your report. Do not post live memory addresses or private code if a smaller pattern reproduces it.
Choosing a protection level
Lite is the public starting point. Advanced access is reviewed individually. More protection may increase output size and startup cost, so use your actual script and environment to decide whether the extra layer is worth it. No client-side obfuscator can make code impossible to reverse.
If a build breaks
First separate a parser error from a runtime error. If the protected file does not parse, send the exact error and a minimal source sample. If it parses but a hook or FFI call behaves differently, identify the first observable difference and the module that owns it. Record the MoonLoader version, LuaJIT version, affected API, original behavior and protected behavior.
When the error happens after a callback rather than on startup, test the callback in isolation with a known input and compare both versions. Also check whether the callback was registered, whether it yielded, and whether an exception was swallowed by the host. These observations narrow a report much faster than a screenshot of the final error alone.
Run the source through Lua Script Doctor for language checks, then open a support ticket from your dashboard with a minimal reproducible example. Do not upload an entire private project just to report a small failure.
Try the Lua obfuscator or read the Lua 5.1 and Luau compatibility guide.
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