diff --git a/scripts/build.sh b/scripts/build.sh
index b98acc6..edfb87b 100755
--- a/scripts/build.sh
+++ b/scripts/build.sh
@@ -20,7 +20,7 @@ cd ../..
 if [[ "$1" == "lua-5.0.3" ]]; then
     emcc -Ithirdparty/$1 thirdparty/$1/lib/liblua.a thirdparty/$1/lib/liblualib.a \
         -s WASM=1 -O3 -o dist/glue/glue-$1.js \
-        -s EXPORTED_RUNTIME_METHODS="['cwrap']" \
+        -s EXPORTED_RUNTIME_METHODS="['cwrap', 'lengthBytesUTF8']" \
         -s MODULARIZE=1 \
         -s ALLOW_TABLE_GROWTH \
         -s EXPORT_NAME="glue" \
diff --git a/src/binding-factory.ts b/src/binding-factory.ts
index 1c99f5f..930c777 100644
--- a/src/binding-factory.ts
+++ b/src/binding-factory.ts
@@ -165,7 +165,7 @@ const lauxBindings: Record<string, lauxBindingFactoryFunc> = {
                 return (this as LauxLib).luaL_loadstring(L, s) || lua.lua_pcall(L, 0, LUA_MULTRET, 0);
             },
             luaL_loadstring: function(L: LuaState, s: string) {
-                return (this as LauxLib).luaL_loadbuffer(L, s, s.length, s);
+                return (this as LauxLib).luaL_loadbuffer(L, s, luaGlue.lengthBytesUTF8(s), s);
             },
             luaL_newstate: luaGlue.cwrap("lua_open", "number", []),
         }
diff --git a/src/glue/glue.ts b/src/glue/glue.ts
index a16d5b6..21c4b09 100644
--- a/src/glue/glue.ts
+++ b/src/glue/glue.ts
@@ -1,5 +1,6 @@
 export interface LuaEmscriptenModule extends EmscriptenModule {
     cwrap: typeof cwrap;
+    lengthBytesUTF8: typeof lengthBytesUTF8;
 }
 
 export type EmscriptenModuleFactorySync<T extends EmscriptenModule = EmscriptenModule> = (