diff --git a/go.mod b/go.mod
index 2fda778..306c99f 100644
--- a/go.mod
+++ b/go.mod
@@ -3,6 +3,7 @@ module github.com/ez-api/ez-api
 go 1.24.5
 
 require (
+	github.com/bytedance/sonic v1.14.0
 	github.com/gin-gonic/gin v1.11.0
 	github.com/redis/go-redis/v9 v9.17.2
 	github.com/swaggo/files v1.0.1
@@ -15,7 +16,6 @@ require (
 
 require (
 	github.com/KyleBanks/depth v1.2.1 // indirect
-	github.com/bytedance/sonic v1.14.0 // indirect
 	github.com/bytedance/sonic/loader v0.3.0 // indirect
 	github.com/cespare/xxhash/v2 v2.3.0 // indirect
 	github.com/cloudwego/base64x v0.1.6 // indirect
diff --git a/internal/service/sync.go b/internal/service/sync.go
index 04c7ffa..07a8588 100644
--- a/internal/service/sync.go
+++ b/internal/service/sync.go
@@ -2,10 +2,10 @@ package service
 
 import (
 	"context"
-	"encoding/json"
 	"fmt"
 	"strings"
 
+	"github.com/bytedance/sonic"
 	"github.com/ez-api/ez-api/internal/model"
 	"github.com/ez-api/ez-api/internal/util"
 	"github.com/redis/go-redis/v9"
@@ -189,7 +189,7 @@ func (s *SyncService) SyncAll(db *gorm.DB) error {
 			Group:   group,
 			Models:  models,
 		}
-		payload, err := json.Marshal(snap)
+		payload, err := sonic.Marshal(snap)
 		if err != nil {
 			return fmt.Errorf("marshal provider %d: %w", p.ID, err)
 		}
@@ -242,7 +242,7 @@ func (s *SyncService) SyncAll(db *gorm.DB) error {
 			SupportsFIM:        m.SupportsFIM,
 			MaxOutputTokens:    m.MaxOutputTokens,
 		}
-		payload, err := json.Marshal(snap)
+		payload, err := sonic.Marshal(snap)
 		if err != nil {
 			return fmt.Errorf("marshal model %s: %w", m.Name, err)
 		}
@@ -257,7 +257,7 @@ func (s *SyncService) SyncAll(db *gorm.DB) error {
 }
 
 func (s *SyncService) hsetJSON(ctx context.Context, key, field string, val interface{}) error {
-	payload, err := json.Marshal(val)
+	payload, err := sonic.Marshal(val)
 	if err != nil {
 		return fmt.Errorf("marshal %s:%s: %w", key, field, err)
 	}
diff --git a/test/go.mod b/test/go.mod
index 2393f36..52a2e98 100644
--- a/test/go.mod
+++ b/test/go.mod
@@ -5,6 +5,6 @@ go 1.24.5
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
-	github.com/stretchr/testify v1.11.1 // indirect
+	github.com/stretchr/testify v1.11.1
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )
diff --git a/test/integration_test.go b/test/integration_test.go
index 028dcbe..90d35b6 100644
--- a/test/integration_test.go
+++ b/test/integration_test.go
@@ -4,13 +4,13 @@ package integration
 
 import (
 	"bytes"
-	"encoding/json"
 	"io"
 	"net/http"
 	"os"
 	"testing"
 	"time"
 
+	"github.com/bytedance/sonic"
 	"github.com/stretchr/testify/require"
 )
 
@@ -54,7 +54,7 @@ func TestEndToEnd(t *testing.T) {
 }
 
 func postJSONWithAuth[T any](t *testing.T, client *http.Client, url string, body interface{}, out T, token string) T {
-	b, err := json.Marshal(body)
+	b, err := sonic.Marshal(body)
 	require.NoError(t, err)
 
 	req, err := http.NewRequest(http.MethodPost, url, bytes.NewReader(b))
@@ -76,7 +76,7 @@ func postJSONWithAuth[T any](t *testing.T, client *http.Client, url string, body
 	if out != nil {
 		data, _ := io.ReadAll(resp.Body)
 		if len(data) > 0 {
-			require.NoError(t, json.Unmarshal(data, out))
+			require.NoError(t, sonic.Unmarshal(data, out))
 		}
 	}
 	return out
diff --git a/test/mock-upstream/main.go b/test/mock-upstream/main.go
index 8a7e7eb..cc26d94 100644
--- a/test/mock-upstream/main.go
+++ b/test/mock-upstream/main.go
@@ -1,9 +1,10 @@
 package main
 
 import (
-	"encoding/json"
 	"log"
 	"net/http"
+
+	"github.com/bytedance/sonic"
 )
 
 func main() {
@@ -30,7 +31,7 @@ func main() {
 			},
 		}
 		w.Header().Set("Content-Type", "application/json")
-		json.NewEncoder(w).Encode(resp)
+		_ = sonic.ConfigDefault.NewEncoder(w).Encode(resp)
 	})
 
 	mux.HandleFunc("/v1/models", func(w http.ResponseWriter, r *http.Request) {
@@ -41,7 +42,7 @@ func main() {
 			},
 		}
 		w.Header().Set("Content-Type", "application/json")
-		json.NewEncoder(w).Encode(resp)
+		_ = sonic.ConfigDefault.NewEncoder(w).Encode(resp)
 	})
 
 	log.Println("mock-upstream listening on :8082")