diff --git a/common/common.go b/common/common.go
index cfbe5ab..6ca5102 100644
--- a/common/common.go
+++ b/common/common.go
@@ -293,3 +293,36 @@ func (f *ArrayFlag) Set(value string) error {
 	*f = append(*f, value)
 	return nil
 }
+
+// FlagsParse parse args to map
+func FlagsParse(args []string, noValArg Set[string], schema map[string]string) map[string]string {
+	keyPos := 0 // position arg
+	keyGen := func() string {
+		keyPos++
+		return fmt.Sprintf("-pos%d", keyPos)
+	}
+	resultMap := make(map[string]string)
+	var key string
+	for _, arg := range args {
+		switch {
+		case len(arg) > 2 && arg[:2] == "--":
+			key = arg[2:]
+			resultMap[key] = ""
+		case len(arg) > 1 && arg[0] == '-':
+			d, ok := schema[arg[1:]]
+			if ok && len(d) > 0 {
+				key = d
+			} else {
+				key = arg[1:]
+			}
+			resultMap[key] = ""
+		case len(arg) > 0 && arg[0] != '-':
+			if noValArg.Has(key) || key == "" {
+				key = keyGen()
+			}
+			resultMap[key] = arg
+			key = ""
+		}
+	}
+	return resultMap
+}
diff --git a/common/common_test.go b/common/common_test.go
new file mode 100644
index 0000000..b985ee5
--- /dev/null
+++ b/common/common_test.go
@@ -0,0 +1,31 @@
+package common
+
+import (
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestFlagsParse(t *testing.T) {
+	args := []string{
+		"-a",
+		"pos-arg1",
+		"-b",
+		"vb",
+		"pos-arg2",
+	}
+	noValArg := MakeSet[string](2)
+	noValArg.Insert("append")
+	schema := map[string]string{
+		"a": "append",
+		"b": "block",
+	}
+	actual := FlagsParse(args, noValArg, schema)
+
+	expected := map[string]string{
+		"-pos1":  "pos-arg1",
+		"-pos2":  "pos-arg2",
+		"append": "",
+		"block":  "vb",
+	}
+	assert.Equal(t, expected, actual)
+}
diff --git a/internal/specialcmd/specialcmd.go b/internal/specialcmd/specialcmd.go
index 6c7e8c7..7959a0e 100644
--- a/internal/specialcmd/specialcmd.go
+++ b/internal/specialcmd/specialcmd.go
@@ -46,7 +46,7 @@ type cellStatus struct {
 func Parse(msg kernel.Message, goExec *goexec.State, execute bool, codeLines []string, usedLines Set[int]) (err error) {
 	status := &cellStatus{}
 	for lineNum := 0; lineNum < len(codeLines); lineNum++ {
-		if _, found := usedLines[lineNum]; found {
+		if usedLines.Has(lineNum) {
 			continue
 		}
 		line := codeLines[lineNum]
@@ -65,9 +65,19 @@ func Parse(msg kernel.Message, goExec *goexec.State, execute bool, codeLines []s
 			if execute {
 				switch cmdType {
 				case '%':
-					err = execInternal(msg, goExec, cmdStr, status)
-					if err != nil {
-						return
+					parts := splitCmd(cmdStr)
+					// optimize...
+					if len(parts) > 0 && parts[0] == "writefile" {
+						cmdBody := parseCmdBody(codeLines, lineNum, usedLines)
+						err = execWriteFile(msg, goExec, parts[1:], cmdBody)
+						if err != nil {
+							return
+						}
+					} else {
+						err = execInternal(msg, goExec, cmdStr, status)
+						if err != nil {
+							return
+						}
 					}
 				case '!':
 					err = execShell(msg, goExec, cmdStr, status)
@@ -95,7 +105,7 @@ func Parse(msg kernel.Message, goExec *goexec.State, execute bool, codeLines []s
 func joinLine(lines []string, fromLine int, usedLines Set[int]) (cmdStr string) {
 	for ; fromLine < len(lines); fromLine++ {
 		cmdStr += lines[fromLine]
-		usedLines[fromLine] = struct{}{}
+		usedLines.Insert(fromLine)
 		if cmdStr[len(cmdStr)-1] != '\\' {
 			return
 		}
@@ -104,6 +114,23 @@ func joinLine(lines []string, fromLine int, usedLines Set[int]) (cmdStr string)
 	return
 }
 
+// parseCmdBody starts from fromLine and joins consecutive lines until the line start with magic symbol( % ! )
+//
+// It returns the joined lines with the '\n', and appends the used lines (including fromLine) to usedLines.
+func parseCmdBody(lines []string, fromLine int, usedLines Set[int]) (cmdBody string) {
+	usedLines.Insert(fromLine)
+	fromLine++
+	for ; fromLine < len(lines); fromLine++ {
+		if len(lines[fromLine]) > 0 && (lines[fromLine][0] == '%' || lines[fromLine][0] == '!') {
+			return
+		}
+		cmdBody += lines[fromLine]
+		cmdBody += "\n"
+		usedLines.Insert(fromLine)
+	}
+	return
+}
+
 // execInternal executes internal configuration commands, see HelpMessage for details.
 //
 // It only returns errors for system errors that will lead to the kernel restart. Syntax errors
@@ -275,6 +302,39 @@ func execInternal(msg kernel.Message, goExec *goexec.State, cmdStr string, statu
 	return nil
 }
 
+// execWriteFile write cell body to file
+func execWriteFile(msg kernel.Message, goExec *goexec.State, args []string, cmdBody string) error {
+	// parse arg
+	noValArg := MakeSet[string](2)
+	noValArg.Insert("append")
+	schema := map[string]string{"a": "append"}
+	parse := FlagsParse(args, noValArg, schema)
+	_, appendMode := parse["append"]
+	filename, hasFileName := parse["-pos1"]
+	if !hasFileName {
+		filename = goExec.UniqueID + ".out"
+	}
+
+	// do write
+	fileFlag := os.O_RDWR | os.O_CREATE
+	if appendMode {
+		fileFlag |= os.O_APPEND
+	} else {
+		fileFlag |= os.O_TRUNC
+	}
+	file, err := os.OpenFile(filename, fileFlag, 0666)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	_, err = file.WriteString(cmdBody)
+	if err != nil {
+		return err
+	}
+	return kernel.PublishWriteStream(msg, kernel.StreamStdout, "write to "+filename+" success\n")
+}
+
 // execInternal executes internal configuration commands, see HelpMessage for details.
 //
 // It only returns errors for system errors that will lead to the kernel restart. Syntax errors
diff --git a/internal/specialcmd/specialcmd_test.go b/internal/specialcmd/specialcmd_test.go
index 59261d2..854557f 100644
--- a/internal/specialcmd/specialcmd_test.go
+++ b/internal/specialcmd/specialcmd_test.go
@@ -61,3 +61,61 @@ func TestDirEnv(t *testing.T) {
 	assert.Equal(t, "/tmp", os.Getenv(protocol.GONB_DIR_ENV))
 	require.NoError(t, s.Stop())
 }
+
+func TestMagicWrite(t *testing.T) {
+	s := newEmptyState(t)
+
+	expected := `fmt.Println("1")
+fmt.Println("2")
+// !*cat main.go
+`
+
+	type TestCase struct {
+		appendMode                 bool
+		filename, src, fileContent string
+	}
+	srcGen := func(testCase *TestCase) {
+		var appendArg string
+		if testCase.appendMode {
+			appendArg = " -a "
+		}
+		testCase.src = `%writefile ` + appendArg + testCase.filename + "\n" + expected + "%%\nfmt.Println(1)"
+	}
+
+	// build test cases
+	testCases := []*TestCase{
+		{false, "", "", expected},
+		{true, "", "", strings.Repeat(expected, 2)},
+		{false, "/tmp/TestMagicWrite.log", "", expected},
+	}
+	for _, testCase := range testCases {
+		srcGen(testCase)
+	}
+
+	// run test cases
+	fileClean := MakeSet[string](4)
+	defer func() {
+		for filename := range fileClean {
+			defer os.Remove(filename)
+		}
+	}()
+	for idx, testCase := range testCases {
+		t.Run(fmt.Sprintf("test-case-%d", idx), func(t *testing.T) {
+			filename := testCase.filename
+			if filename == "" {
+				filename = s.UniqueID + ".out"
+			}
+			fileClean.Insert(filename)
+
+			var msg kernel.Message
+			usedLines := MakeSet[int]()
+			lines := strings.Split(testCase.src, "\n")
+			err := Parse(msg, s, true, lines, usedLines)
+			require.NoError(t, err)
+
+			fileBytes, err := os.ReadFile(filename)
+			require.NoError(t, err)
+			assert.Equal(t, testCase.fileContent, string(fileBytes))
+		})
+	}
+}