diff --git a/env_test.go b/env_test.go
index 421adb7..8f09dff 100644
--- a/env_test.go
+++ b/env_test.go
@@ -4,8 +4,10 @@ import (
 	"context"
 	"os"
 	"testing"
+	"time"
 
 	"go.unistack.org/micro/v3/config"
+	rutil "go.unistack.org/micro/v3/util/reflect"
 )
 
 type Config struct {
@@ -17,6 +19,52 @@ type Config struct {
 	MapIntValue    map[string]int    `env:"MAP_INT"`
 }
 
+func TestMerge(t *testing.T) {
+	ctx := context.Background()
+	type Nested struct {
+		Name string `env:"NAME_VALUE"`
+	}
+	type Cfg struct {
+		Name   string `env:"NAME_VALUE"`
+		Nested Nested
+	}
+
+	conf := &Cfg{}
+
+	cfg := NewConfig(config.Struct(conf))
+
+	if err := cfg.Init(); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := cfg.Load(ctx, config.LoadOverride(true), config.LoadAppend(true)); err != nil {
+		t.Fatal(err)
+	}
+
+	w, err := cfg.Watch(ctx, config.WatchInterval(50*time.Millisecond, 500*time.Millisecond))
+	defer func() {
+		if err := w.Stop(); err != nil {
+			t.Fatal(err)
+		}
+	}()
+
+	os.Setenv("NAME_VALUE", "after")
+	changes, err := w.Next()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	for k, v := range changes {
+		if err := rutil.SetFieldByPath(conf, v, k); err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	if conf.Name != "after" || conf.Nested.Name != "after" {
+		t.Fatalf("changes %#+v not applied to %#+v", changes, conf)
+	}
+}
+
 func TestLoad(t *testing.T) {
 	ctx := context.Background()
 	conf := &Config{StringValue: "before_load"}
@@ -63,8 +111,6 @@ func TestLoad(t *testing.T) {
 	if len(conf.MapIntValue) != 2 {
 		t.Fatalf("something wrong with env config: %#+v", conf.MapIntValue)
 	}
-
-	t.Logf("cfg %#+v", conf)
 }
 
 func TestSave(t *testing.T) {
diff --git a/go.mod b/go.mod
index 2067e04..ae5e8b2 100644
--- a/go.mod
+++ b/go.mod
@@ -4,5 +4,5 @@ go 1.16
 
 require (
 	github.com/imdario/mergo v0.3.12
-	go.unistack.org/micro/v3 v3.8.10
+	go.unistack.org/micro/v3 v3.8.11
 )
diff --git a/go.sum b/go.sum
index d7b456f..93f41b9 100644
--- a/go.sum
+++ b/go.sum
@@ -9,8 +9,8 @@ github.com/patrickmn/go-cache v2.1.0+incompatible/go.mod h1:3Qf8kWWT7OJRJbdiICTK
 github.com/silas/dag v0.0.0-20210626123444-3804bac2d6d4/go.mod h1:7RTUFBdIRC9nZ7/3RyRNH1bdqIShrDejd1YbLwgPS+I=
 go.unistack.org/micro-proto/v3 v3.1.0 h1:q39FwjFiRZn+Ux/tt+d3bJTmDtsQQWa+3SLYVo1vLfA=
 go.unistack.org/micro-proto/v3 v3.1.0/go.mod h1:DpRhYCBXlmSJ/AAXTmntvlh7kQkYU6eFvlmYAx4BQS8=
-go.unistack.org/micro/v3 v3.8.10 h1:ZMKGGalqkZc677S5BmSPTAMZAE4q3u2FuqCrCd1TO7g=
-go.unistack.org/micro/v3 v3.8.10/go.mod h1:KMMmOmbgo/D52/rCAbqeKbBsgEEbSKM69he54J3ZIuA=
+go.unistack.org/micro/v3 v3.8.11 h1:Wv1YopcYNcsN3bW8Mv8v6AF99s0uKBtWQ1M/Ag8QLec=
+go.unistack.org/micro/v3 v3.8.11/go.mod h1:KMMmOmbgo/D52/rCAbqeKbBsgEEbSKM69he54J3ZIuA=
 golang.org/x/net v0.0.0-20210928044308-7d9f5e0b762b/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=