diff --git a/daemon/handlers.sync.go b/daemon/handlers.sync.go
index 83af73c..5223135 100644
--- a/daemon/handlers.sync.go
+++ b/daemon/handlers.sync.go
@@ -2,6 +2,7 @@ package daemon
 
 import (
 	"context"
+	"encoding/json"
 	"log/slog"
 	"time"
 
@@ -74,7 +75,7 @@ func handlePubSubSync(ctx context.Context, socketMsgPayload interface{}) error {
 				slog.Error("Failed to encrypt key", slog.Any("err", err))
 			}
 
-			buf, err := msgpack.Marshal(payload)
+			buf, err := json.Marshal(payload)
 
 			if err != nil {
 				slog.Error("Failed to marshal payload", slog.Any("err", err))
diff --git a/model/handshake.go b/model/handshake.go
index 2d5fdd1..eba1975 100644
--- a/model/handshake.go
+++ b/model/handshake.go
@@ -12,7 +12,6 @@ import (
 	"time"
 
 	"github.com/sirupsen/logrus"
-	"github.com/vmihailenco/msgpack/v5"
 	"go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
 )
 
@@ -51,7 +50,7 @@ func (hs handshakeService) send(ctx context.Context, path string, jsonData []byt
 		return
 	}
 
-	req.Header.Set("Content-Type", "application/msgpack")
+	req.Header.Set("Content-Type", "application/json")
 	req.Header.Set("User-Agent", fmt.Sprintf("shelltimeCLI@%s", commitID))
 	resp, err := hc.Do(req)
 	if err != nil {
@@ -103,7 +102,7 @@ func (hs handshakeService) Init(ctx context.Context) (string, error) {
 		OSVersion: sysInfo.Version,
 	}
 
-	jsonData, err := msgpack.Marshal(data)
+	jsonData, err := json.Marshal(data)
 	if err != nil {
 		logrus.Errorln(err)
 		return "", err
@@ -130,7 +129,7 @@ func (hs handshakeService) Check(ctx context.Context, handshakeId string) (token
 		EncodedID: handshakeId,
 	}
 
-	jsonData, err := msgpack.Marshal(data)
+	jsonData, err := json.Marshal(data)
 	if err != nil {
 		logrus.Errorln(err)
 		return "", err
diff --git a/model/handshake_test.go b/model/handshake_test.go
index 6ee8e29..fcf8f5d 100644
--- a/model/handshake_test.go
+++ b/model/handshake_test.go
@@ -2,13 +2,13 @@ package model
 
 import (
 	"context"
+	"encoding/json"
 	"net/http"
 	"net/http/httptest"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/suite"
-	"github.com/vmihailenco/msgpack/v5"
 )
 
 type handshakeTestSuite struct {
@@ -21,12 +21,12 @@ func (s *handshakeTestSuite) TestHandshakeInitSuccess() {
 		// Verify request
 		assert.Equal(t, "POST", r.Method)
 		assert.Equal(t, "/api/v1/handshake/init", r.URL.Path)
-		assert.Equal(t, "application/msgpack", r.Header.Get("Content-Type"))
+		assert.Equal(t, "application/json", r.Header.Get("Content-Type"))
 		assert.Contains(t, r.Header.Get("User-Agent"), "shelltimeCLI@")
 
 		// Decode request body
 		var payload handshakeInitRequest
-		err := msgpack.NewDecoder(r.Body).Decode(&payload)
+		err := json.NewDecoder(r.Body).Decode(&payload)
 		assert.NoError(t, err)
 
 		// Verify payload
@@ -74,11 +74,11 @@ func (s *handshakeTestSuite) TestHandshakeCheckWithToken() {
 		// Verify request
 		assert.Equal(t, "POST", r.Method)
 		assert.Equal(t, "/api/v1/handshake/check", r.URL.Path)
-		assert.Equal(t, "application/msgpack", r.Header.Get("Content-Type"))
+		assert.Equal(t, "application/json", r.Header.Get("Content-Type"))
 
 		// Decode request body
 		var payload handshakeCheckRequest
-		err := msgpack.NewDecoder(r.Body).Decode(&payload)
+		err := json.NewDecoder(r.Body).Decode(&payload)
 		assert.NoError(t, err)
 
 		// Verify payload