diff --git a/c/lua/_demo/dump/load/load.go b/c/lua/_demo/dump/load/load.go
new file mode 100644
index 00000000..32d9cd61
--- /dev/null
+++ b/c/lua/_demo/dump/load/load.go
@@ -0,0 +1,68 @@
+package main
+
+import (
+	"os"
+	"unsafe"
+
+	"github.com/goplus/llgo/c"
+	"github.com/goplus/llgo/c/lua"
+)
+
+func reader(L *lua.State, data c.Pointer, size *c.Ulong) *c.Char {
+	file := (*os.File)(data)
+
+	fileInfo, err := file.Stat()
+	if err != nil {
+		return nil
+	}
+	fileSize := fileInfo.Size()
+
+	buffer := make([]byte, fileSize)
+	bytesRead, err := file.Read(buffer)
+	if err != nil {
+		return nil
+	}
+
+	*size = c.Ulong(bytesRead)
+
+	if bytesRead > 0 {
+		return (*c.Char)(unsafe.Pointer(unsafe.SliceData(buffer)))
+	}
+
+	return nil
+}
+
+func main() {
+	L := lua.Newstate()
+	defer L.Close()
+	L.Openlibs()
+
+	file, err := os.Open("../llgofunc.luac")
+	if err != nil {
+		c.Printf(c.Str("Failed to open file for reading\n"))
+		return
+	}
+	defer file.Close()
+
+	if L.Load(reader, c.Pointer(file), c.Str("greet"), nil) != lua.OK {
+		c.Printf(c.Str("Failed to dump Lua function\n"))
+	}
+
+	c.Printf(c.Str("Stack size before call: %d\n"), L.Gettop())
+	c.Printf(c.Str("Top element type after call: %s\n"), L.Typename(L.Type(-1)))
+
+	L.Pushstring(c.Str("World"))
+	if L.Pcall(1, 1, 0) != lua.OK {
+		c.Printf(c.Str("Failed to call function: %s\n"))
+	}
+
+	if L.Isstring(-1) != 0 {
+		c.Printf(c.Str("Result: %s\n"), L.Tostring(-1))
+	}
+}
+
+/* Expected output:
+Stack size before call: 1
+Top element type after call: function
+Result: Hello, World!
+*/
diff --git a/c/lua/_demo/dump/save/save.go b/c/lua/_demo/dump/save/save.go
new file mode 100644
index 00000000..e94cc2e5
--- /dev/null
+++ b/c/lua/_demo/dump/save/save.go
@@ -0,0 +1,56 @@
+package main
+
+import (
+	"os"
+	"unsafe"
+
+	"github.com/goplus/llgo/c"
+	"github.com/goplus/llgo/c/lua"
+)
+
+func writer(L *lua.State, p c.Pointer, sz c.Ulong, ud c.Pointer) c.Int {
+	file := (*os.File)(ud)
+	data := unsafe.Slice((*byte)(p), sz)
+
+	n, err := file.Write(data)
+	if err != nil || n != int(sz) {
+		return 1
+	}
+
+	return lua.OK
+}
+
+func main() {
+	L := lua.Newstate()
+	defer L.Close()
+	L.Openlibs()
+
+	if res := L.Loadstring(c.Str(`
+	function greet(name)
+		return 'Hello, ' .. name .. '!'
+	end
+	return greet
+	`)); res != lua.OK {
+		c.Printf(c.Str("error: %s\n"), L.Tostring(-1))
+	}
+
+	if res := L.Pcall(0, 1, 0); res != lua.OK {
+		c.Printf(c.Str("error: %s\n"), L.Tostring(-1))
+	}
+
+	if !L.Isfunction(-1) {
+		c.Printf(c.Str("Expected a function, but got %s"), L.Typename(L.Type(-1)))
+	}
+
+	file, err := os.Create("../llgofunc.luac")
+	if err != nil {
+		c.Printf(c.Str("Failed to open file for writing\n"))
+		return
+	}
+	defer file.Close()
+
+	if L.Dump(writer, c.Pointer(file), 0) != lua.OK {
+		c.Printf(c.Str("Failed to dump Lua function\n"))
+	}
+
+}
diff --git a/c/lua/lua.go b/c/lua/lua.go
index d013cfdb..7d3ffb13 100644
--- a/c/lua/lua.go
+++ b/c/lua/lua.go
@@ -78,8 +78,6 @@ const (
 type Number = c.Double
 
 // /* type for integer functions */
-// TODO(zzy):consider dynamic size
-
 type Integer = c.Int
 
 // /* unsigned integer type */
@@ -106,8 +104,11 @@ type KFunction func(L *State, status c.Int, ctx KContext) c.Int
 // ** Type for functions that read/write blocks when loading/dumping Lua chunks
 // */
 
-// typedef const char * (*lua_Reader) (State *L, void *ud, size_t *sz);
-// typedef int (*lua_Writer) (State *L, const void *p, size_t sz, void *ud);
+// llgo:type C
+type Reader func(L *State, ud c.Pointer, sz *c.Ulong) *c.Char
+
+// llgo:type C
+type Writer func(L *State, p c.Pointer, sz c.Ulong, ud c.Pointer) c.Int
 
 // /*
 // ** Type for memory-allocation functions
@@ -352,9 +353,11 @@ func (L *State) Pcall(nargs c.Int, nresults c.Int, errfunc c.Int) c.Int {
 	return L.Pcallk(nargs, nresults, errfunc, nil, nil)
 }
 
-// int   (lua_load) (State *L, lua_Reader reader, void *dt, const char *chunkname, const char *mode);
+// llgo:link (*State).Load C.lua_load
+func (L *State) Load(reader Reader, dt c.Pointer, chunkname *c.Char, mode *c.Char) c.Int { return 0 }
 
-// int (lua_dump) (State *L, lua_Writer writer, void *data, int strip);
+// llgo:link (*State).Dump C.lua_dump
+func (L *State) Dump(writer Writer, data c.Pointer, strip c.Int) c.Int { return 0 }
 
 // /*
 // ** coroutine functions