diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index bdeb9fd..4e929c7 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -5,13 +5,13 @@ jobs:
 
   build:
     name: Build
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     steps:
 
-    - name: Set up Go 1.13
-      uses: actions/setup-go@v1
+    - name: Set up Go 1.19
+      uses: actions/setup-go@v4
       with:
-        go-version: 1.13
+        go-version: 1.19
       id: go
 
     - name: Install Cross binutils
@@ -19,7 +19,7 @@ jobs:
         sudo apt-get install -y gcc-aarch64-linux-gnu
 
     - name: Check out code into the Go module directory
-      uses: actions/checkout@v2
+      uses: actions/checkout@v4
 
     - name: Build
       run: |
@@ -34,14 +34,13 @@ jobs:
         done
 
     - name: Keep artifacts
-      uses: actions/upload-artifact@v2
+      uses: actions/upload-artifact@v3
       with:
         name: 'tunaccount-linux-arm64'
         path: 'tunaccount-linux-arm64-bin.tar.gz'
 
     - name: Keep artifacts
-      uses: actions/upload-artifact@v2
+      uses: actions/upload-artifact@v3
       with:
         name: 'tunaccount-linux-amd64'
         path: 'tunaccount-linux-amd64-bin.tar.gz'
-
diff --git a/ldap.go b/ldap.go
index 707d1f7..f16ec3f 100644
--- a/ldap.go
+++ b/ldap.go
@@ -180,9 +180,7 @@ func handleSearch(w ldap.ResponseWriter, m *ldap.Message) {
 			e.AddAttribute("loginShell", ldapMsg.AttributeValue(u.LoginShell))
 			e.AddAttribute("homeDirectory", ldapMsg.AttributeValue(fmt.Sprintf("/home/%s", u.Username)))
 			e.AddAttribute("userPassword", ldapMsg.AttributeValue(u.Password))
-			e.AddAttribute("objectClass", "top")
-			e.AddAttribute("objectClass", "posixAccount")
-			e.AddAttribute("objectClass", "shadowAccount")
+			e.AddAttribute("objectClass", "top", "posixAccount", "shadowAccount")
 			e.AddAttribute("shadowMax", "99999")
 			w.Write(e)
 		}
@@ -192,11 +190,12 @@ func handleSearch(w ldap.ResponseWriter, m *ldap.Message) {
 			e := ldap.NewSearchResultEntry(fmt.Sprintf("cn=%s,ou=groups,%s", g.Name, dcfg.LDAP.Suffix))
 			e.AddAttribute("cn", ldapMsg.AttributeValue(g.Name))
 			e.AddAttribute("gidNumber", ldapMsg.AttributeValue(strconv.Itoa(g.GID)))
+			members := []ldapMsg.AttributeValue{}
 			for _, username := range g.Members {
-				e.AddAttribute("memberUid", ldapMsg.AttributeValue(username))
+				members = append(members, ldapMsg.AttributeValue(username))
 			}
-			e.AddAttribute("objectClass", "top")
-			e.AddAttribute("objectClass", "posixGroup")
+			e.AddAttribute("memberUid", members...)
+			e.AddAttribute("objectClass", "top", "posixGroup")
 			w.Write(e)
 		}
 	}