diff --git a/.github/workflows/test.yaml b/.github/workflows/test.yaml
index 30948bb..4fcd39c 100644
--- a/.github/workflows/test.yaml
+++ b/.github/workflows/test.yaml
@@ -4,7 +4,7 @@ jobs:
   test:
     strategy:
       matrix:
-        go-version: [1.13, 1.14, 1.15, 1.16, 1.17, 1.18]
+        go-version: [1.16, 1.17, 1.18, 1.19]
         platform: [ubuntu-latest, macos-latest, windows-latest]
     runs-on: ${{ matrix.platform }}
     steps:
diff --git a/go.mod b/go.mod
index 3756da7..0a60671 100644
--- a/go.mod
+++ b/go.mod
@@ -1,6 +1,6 @@
 module github.com/jxsl13/backupfs
 
-go 1.13
+go 1.16
 
 require (
 	github.com/golang/mock v1.6.0
diff --git a/internal/test.go b/internal/test.go
index 582ef93..7b6b18a 100644
--- a/internal/test.go
+++ b/internal/test.go
@@ -1,7 +1,7 @@
 package internal
 
 import (
-	"io/ioutil"
+	"io"
 	"os"
 	"path/filepath"
 	"sort"
@@ -35,7 +35,7 @@ func FileMustContainText(t *testing.T, fs afero.Fs, path, content string) {
 	f, err := fs.Open(path)
 	require.NoError(err)
 	defer f.Close()
-	b, err := ioutil.ReadAll(f)
+	b, err := io.ReadAll(f)
 	require.NoError(err)
 
 	require.Equal(string(b), content)