diff --git a/file.go b/file.go
index d162360..2225cfc 100644
--- a/file.go
+++ b/file.go
@@ -50,7 +50,7 @@ func (c *fileConfig) Init(opts ...config.Option) error {
 	return nil
 }
 
-func (c *fileConfig) Load(ctx context.Context) error {
+func (c *fileConfig) Load(ctx context.Context, opts ...config.LoadOption) error {
 	for _, fn := range c.opts.BeforeLoad {
 		if err := fn(ctx, c); err != nil && !c.opts.AllowFail {
 			return err
@@ -69,7 +69,15 @@ func (c *fileConfig) Load(ctx context.Context) error {
 			if err == nil {
 				err = c.opts.Codec.Unmarshal(buf, src)
 				if err == nil {
-					err = mergo.Merge(c.opts.Struct, src, mergo.WithOverride, mergo.WithTypeCheck, mergo.WithAppendSlice)
+					options := config.NewLoadOptions(opts...)
+					mopts := []func(*mergo.Config){mergo.WithTypeCheck}
+					if options.Override {
+						mopts = append(mopts, mergo.WithOverride)
+					}
+					if options.Append {
+						mopts = append(mopts, mergo.WithAppendSlice)
+					}
+					err = mergo.Merge(c.opts.Struct, src, mopts...)
 				}
 			}
 		}
@@ -87,7 +95,7 @@ func (c *fileConfig) Load(ctx context.Context) error {
 	return nil
 }
 
-func (c *fileConfig) Save(ctx context.Context) error {
+func (c *fileConfig) Save(ctx context.Context, opts ...config.SaveOption) error {
 	for _, fn := range c.opts.BeforeSave {
 		if err := fn(ctx, c); err != nil && !c.opts.AllowFail {
 			return err
diff --git a/go.mod b/go.mod
index af9e94d..23cf5c8 100644
--- a/go.mod
+++ b/go.mod
@@ -4,5 +4,5 @@ go 1.16
 
 require (
 	github.com/imdario/mergo v0.3.12
-	github.com/unistack-org/micro/v3 v3.3.17
+	github.com/unistack-org/micro/v3 v3.4.0
 )
diff --git a/go.sum b/go.sum
index d490443..3e10b38 100644
--- a/go.sum
+++ b/go.sum
@@ -5,9 +5,9 @@ github.com/imdario/mergo v0.3.12 h1:b6R2BslTbIEToALKP7LxUvijTsNI9TAe80pLWN2g/HU=
 github.com/imdario/mergo v0.3.12/go.mod h1:jmQim1M+e3UYxmgPu/WyfjB3N3VflVyUjjjwH0dnCYA=
 github.com/patrickmn/go-cache v2.1.0+incompatible/go.mod h1:3Qf8kWWT7OJRJbdiICTKqZju1ZixQ/KpMGzzAfe6+WQ=
 github.com/silas/dag v0.0.0-20210121180416-41cf55125c34/go.mod h1:7RTUFBdIRC9nZ7/3RyRNH1bdqIShrDejd1YbLwgPS+I=
-github.com/unistack-org/micro/v3 v3.3.17 h1:WcyS7InP0DlS/JpRQGLh5sG6VstkdHJbgpMp+gmHmwg=
-github.com/unistack-org/micro/v3 v3.3.17/go.mod h1:022EOEZZ789hZY3yB5ZSMXU6jLiadBgcNB/cpediV3c=
-golang.org/x/net v0.0.0-20210423184538-5f58ad60dda6/go.mod h1:OJAsFXCWl8Ukc7SiCT/9KSuxbyM7479/AVlXFRxuMCk=
+github.com/unistack-org/micro/v3 v3.4.0 h1:z9F3lgAb2j4cZ1ib5qBj66JPYUAzR4sNIJqUDjVwyVQ=
+github.com/unistack-org/micro/v3 v3.4.0/go.mod h1:LXmPfbJnJNvL0kQs8HfnkV3Wya2Wb+C7keVq++RCZnk=
+golang.org/x/net v0.0.0-20210510120150-4163338589ed/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=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=