diff --git a/luprex/cpp/core/luasnap.cpp b/luprex/cpp/core/luasnap.cpp
index 1502cf83..8505b4d5 100644
--- a/luprex/cpp/core/luasnap.cpp
+++ b/luprex/cpp/core/luasnap.cpp
@@ -36,7 +36,7 @@ void LuaSnap::serialize(StreamBuffer *sb) {
     // lua variables that we'll need.
     LuaVar key, value;
     LuaRet permstable, regcopy;
-    LuaOldStack LS(state_, permstable, regcopy, key, value);
+    LuaDefStack LS(state_, permstable, regcopy, key, value);
 
     // Construct a copy of the registry table.
     LS.set(regcopy, LuaNewTable);
@@ -93,7 +93,7 @@ void LuaSnap::deserialize(StreamBuffer *sb) {
     // Set up a stack frame.
     LuaArg permstable, regcopy;
     LuaVar key, value;
-    LuaOldStack LS(state_, permstable, regcopy, key, value);
+    LuaDefStack LS(state_, permstable, regcopy, key, value);
 
     assert(LS.istable(regcopy));
 
diff --git a/luprex/cpp/core/luastack.cpp b/luprex/cpp/core/luastack.cpp
index 3adf714f..d223e046 100644
--- a/luprex/cpp/core/luastack.cpp
+++ b/luprex/cpp/core/luastack.cpp
@@ -235,7 +235,7 @@ eng::string LuaCoreStack::classname(LuaSlot tab) const {
     eng::string result;
     if ((istable(tab)) && (gettabletype(tab) == LUA_TT_CLASS)) {
         LuaVar classes, name, dup;
-        LuaOldStack LS(L_, classes, name, dup);
+        LuaExtStack LS(L_, classes, name, dup);
         // Get the classes table from the registry.
         LS.rawget(classes, LuaRegistry, "classes");
 
@@ -245,9 +245,7 @@ eng::string LuaCoreStack::classname(LuaSlot tab) const {
         if (LS.isstring(name)) {
             LS.rawget(dup, classes, name);
             if (LS.rawequal(dup, tab)) {
-                result = LS.ckstring(name);
-                LS.result();
-                return result;
+                return LS.ckstring(name);
             }
         }
 
@@ -255,9 +253,7 @@ eng::string LuaCoreStack::classname(LuaSlot tab) const {
         LS.set(name, LuaNil);
         while (LS.next(classes, name, dup)) {
             if (LS.rawequal(dup, tab)) {
-                result = LS.ckstring(name);
-                LS.result();
-                return result;
+                return LS.ckstring(name);
             }
         }
     }
@@ -267,52 +263,43 @@ eng::string LuaCoreStack::classname(LuaSlot tab) const {
 eng::string LuaCoreStack::getclass(LuaSlot classtab, LuaSlot classname) const {
     lua_checkstack(L_, 20);
     LuaVar globtab, cname;
-    LuaOldStack LS(L_, globtab, cname);
+    LuaExtStack LS(L_, globtab, cname);
     LS.getglobaltable(globtab);
 
     if (LS.isstring(classname)) {
         if (!validclassname(LS.ckstring(classname))) {
             eng::string err = "invalid class name: " + LS.ckstring(classname);
-            LS.result();
             return err;
         }
         LS.rawget(classtab, globtab, classname);
         if (!LS.istable(classtab)) {
             eng::string err = "not a class: " + LS.ckstring(classname);
-            LS.result();
             return err;
         }
         LS.rawget(cname, classtab, "__class");
         if (!LS.rawequal(cname, classname)) {
             eng::string err = "not a valid class: " + LS.ckstring(classname);
-            LS.result();
             return err;
         }
-        LS.result();
         return "";
     } else if (LS.istable(classname)) {
         LS.rawget(cname, classname, "__class");
         if (!LS.isstring(cname)) {
             eng::string err = "table is not a class.";
-            LS.result();
             return err;
         }
         if (!validclassname(LS.ckstring(cname))) {
             eng::string err = "invalid class name: " + LS.ckstring(cname);
-            LS.result();
             return err;
         }
         LS.rawget(classtab, globtab, cname);
         if (!LS.rawequal(classtab, classname)) {
             eng::string err = "not a valid class: " + LS.ckstring(cname);
-            LS.result();
             return err;
         }
-        LS.result();
         return "";
     } else {
         eng::string err = "getclass expects a string or a classtab";
-        LS.result();
         return err;
     }
 }
@@ -326,9 +313,8 @@ eng::string LuaCoreStack::getclass(LuaSlot tab, std::string_view name) const {
 }
 
 void LuaCoreStack::makeclass(LuaSlot classtab, LuaSlot classname) const {
-    lua_checkstack(L_, 20);
     LuaVar classes, globtab, cname;
-    LuaOldStack LS(L_, classes, globtab, cname);
+    LuaExtStack LS(L_, classes, globtab, cname);
 
     // Validate the class name.
     assert(LS.validclassname(classname));
@@ -356,9 +342,6 @@ void LuaCoreStack::makeclass(LuaSlot classtab, LuaSlot classname) const {
     LS.settabletype(classtab, LUA_TT_CLASS);
     LS.rawset(classtab, "__class", classname);
     LS.rawset(classtab, "__index", classtab);
-
-    // Put the stack back.
-    LS.result();
 }
 
 void LuaCoreStack::makeclass(LuaSlot tab, std::string_view name) const {
@@ -370,7 +353,7 @@ void LuaCoreStack::makeclass(LuaSlot tab, std::string_view name) const {
 
 void LuaCoreStack::maketan(LuaSlot tab, int64_t id) const {
     LuaVar tangibles, metatab;
-    LuaOldStack LS(L_, tangibles, metatab);
+    LuaExtStack LS(L_, tangibles, metatab);
     
     // Try to get the existing tangible.
     LS.rawget(tangibles, LuaRegistry, "tangibles");
@@ -378,7 +361,6 @@ void LuaCoreStack::maketan(LuaSlot tab, int64_t id) const {
 
     // If we succeeded, return it.
     if (LS.istable(tab)) {
-        LS.result();
         return;
     }
 
@@ -397,8 +379,6 @@ void LuaCoreStack::maketan(LuaSlot tab, int64_t id) const {
 
     // Store the database into the tangibles table.
     LS.rawset(tangibles, id, tab);
-
-    LS.result();
 }
 
 
diff --git a/luprex/cpp/core/world-accessor.cpp b/luprex/cpp/core/world-accessor.cpp
index 6ca4444a..aa3a7407 100644
--- a/luprex/cpp/core/world-accessor.cpp
+++ b/luprex/cpp/core/world-accessor.cpp
@@ -807,7 +807,7 @@ int lfn_http_request(lua_State *L, const char *method) {
 
     LuaArg request;
     LuaRet response;
-    LuaOldStack LS(L, request, response);
+    LuaDefStack LS(L, request, response);
     LuaKeywordParser kp(LS, request);
     HttpClientRequest req;