diff --git a/conv.go b/conv.go
index db588e3..b3b23f2 100644
--- a/conv.go
+++ b/conv.go
@@ -1,3 +1,5 @@
+// SPDX-FileCopyrightText: 2014-2024 caixw
+//
 // SPDX-License-Identifier: MIT
 
 package conv
diff --git a/conv_test.go b/conv_test.go
index 5469860..dad93d3 100644
--- a/conv_test.go
+++ b/conv_test.go
@@ -1,3 +1,5 @@
+// SPDX-FileCopyrightText: 2014-2024 caixw
+//
 // SPDX-License-Identifier: MIT
 
 package conv
@@ -5,7 +7,7 @@ package conv
 import (
 	"testing"
 
-	"github.com/issue9/assert/v3"
+	"github.com/issue9/assert/v4"
 )
 
 func TestMustBool(t *testing.T) {
diff --git a/doc.go b/doc.go
index aa78f69..b79f8d4 100644
--- a/doc.go
+++ b/doc.go
@@ -1,3 +1,5 @@
+// SPDX-FileCopyrightText: 2014-2024 caixw
+//
 // SPDX-License-Identifier: MIT
 
 // Package conv 提供了基础的类型转换功能
diff --git a/go.mod b/go.mod
index 7c5ac09..5f95bf0 100644
--- a/go.mod
+++ b/go.mod
@@ -1,5 +1,5 @@
 module github.com/issue9/conv
 
-require github.com/issue9/assert/v3 v3.1.0
+require github.com/issue9/assert/v4 v4.1.1
 
 go 1.18
diff --git a/go.sum b/go.sum
index 55b7465..e03cb71 100644
--- a/go.sum
+++ b/go.sum
@@ -1,2 +1,2 @@
-github.com/issue9/assert/v3 v3.1.0 h1:oxLFXS7QnBKI4lB31pRoYO96yErkWAJtR7iv+LNjAPg=
-github.com/issue9/assert/v3 v3.1.0/go.mod h1:yft/uaskRpwQTyBT3n1zRl91SR1wNlO4fLZHzOa4bdM=
+github.com/issue9/assert/v4 v4.1.1 h1:OhPE8SB8n/qZCNGLQa+6MQtr/B3oON0JAVj68k8jJlc=
+github.com/issue9/assert/v4 v4.1.1/go.mod h1:v7qDRXi7AsaZZNh8eAK2rkLJg5/clztqQGA1DRv9Lv4=
diff --git a/obj.go b/obj.go
index ce39599..50f2eb4 100644
--- a/obj.go
+++ b/obj.go
@@ -1,3 +1,5 @@
+// SPDX-FileCopyrightText: 2014-2024 caixw
+//
 // SPDX-License-Identifier: MIT
 
 package conv
diff --git a/obj_test.go b/obj_test.go
index 0193ab3..99e878e 100644
--- a/obj_test.go
+++ b/obj_test.go
@@ -1,3 +1,5 @@
+// SPDX-FileCopyrightText: 2014-2024 caixw
+//
 // SPDX-License-Identifier: MIT
 
 package conv
@@ -6,7 +8,7 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/issue9/assert/v3"
+	"github.com/issue9/assert/v4"
 )
 
 type A1 struct {
diff --git a/types.go b/types.go
index 63d4feb..df6aaa9 100644
--- a/types.go
+++ b/types.go
@@ -1,3 +1,5 @@
+// SPDX-FileCopyrightText: 2014-2024 caixw
+//
 // SPDX-License-Identifier: MIT
 
 package conv
diff --git a/value.go b/value.go
index 24a023c..29c0859 100644
--- a/value.go
+++ b/value.go
@@ -1,3 +1,5 @@
+// SPDX-FileCopyrightText: 2014-2024 caixw
+//
 // SPDX-License-Identifier: MIT
 
 package conv
diff --git a/value_test.go b/value_test.go
index f82e0e0..e34af0d 100644
--- a/value_test.go
+++ b/value_test.go
@@ -1,3 +1,5 @@
+// SPDX-FileCopyrightText: 2014-2024 caixw
+//
 // SPDX-License-Identifier: MIT
 
 package conv
@@ -6,7 +8,7 @@ import (
 	"reflect"
 	"testing"
 
-	"github.com/issue9/assert/v3"
+	"github.com/issue9/assert/v4"
 )
 
 func TestValue(t *testing.T) {