diff --git a/flag.go b/flag.go
index a98e11d..b89a278 100644
--- a/flag.go
+++ b/flag.go
@@ -43,11 +43,24 @@ func (c *flagConfig) Init(opts ...config.Option) error {
 	for _, o := range opts {
 		o(&c.opts)
 	}
+
+	if err := config.DefaultBeforeInit(c.opts.Context, c); err != nil && !c.opts.AllowFail {
+		return err
+	}
+
 	c.configure()
 
 	fields, err := rutil.StructFields(c.opts.Struct)
 	if err != nil {
-		return err
+		if !c.opts.AllowFail {
+			return err
+		}
+
+		if err := config.DefaultAfterInit(c.opts.Context, c); err != nil && !c.opts.AllowFail {
+			return err
+		}
+
+		return nil
 	}
 
 	for _, sf := range fields {
@@ -84,10 +97,13 @@ func (c *flagConfig) Init(opts ...config.Option) error {
 		}
 
 		if err != nil {
-			c.opts.Logger.Errorf(c.opts.Context, "flag init error: %v", err)
 			if !c.opts.AllowFail {
 				return err
 			}
+			if err := config.DefaultAfterInit(c.opts.Context, c); err != nil && !c.opts.AllowFail {
+				return err
+			}
+
 			return nil
 		}
 
@@ -120,26 +136,52 @@ func (c *flagConfig) Init(opts ...config.Option) error {
 			err = c.flagMap(sf.Value, fn, fv, fd)
 		}
 		if err != nil {
-			c.opts.Logger.Errorf(c.opts.Context, "flag init error: %v", err)
 			if !c.opts.AllowFail {
 				return err
 			}
+
+			if err := config.DefaultAfterInit(c.opts.Context, c); err != nil && !c.opts.AllowFail {
+				return err
+			}
+
 			return nil
 		}
 	}
 
+	if err := config.DefaultAfterInit(c.opts.Context, c); err != nil && !c.opts.AllowFail {
+		return err
+	}
+
 	return nil
 }
 
 func (c *flagConfig) Load(ctx context.Context, opts ...config.LoadOption) error {
 	options := config.NewLoadOptions(opts...)
 	_ = options
+
+	if err := config.DefaultBeforeLoad(ctx, c); err != nil && !c.opts.AllowFail {
+		return err
+	}
+
+	if err := config.DefaultAfterLoad(ctx, c); err != nil && !c.opts.AllowFail {
+		return err
+	}
+
 	// TODO: allow merge, append and so
 	flag.Parse()
+
 	return nil
 }
 
 func (c *flagConfig) Save(ctx context.Context, opts ...config.SaveOption) error {
+	if err := config.DefaultBeforeSave(ctx, c); err != nil && !c.opts.AllowFail {
+		return err
+	}
+
+	if err := config.DefaultAfterSave(ctx, c); err != nil && !c.opts.AllowFail {
+		return err
+	}
+
 	return nil
 }
 
diff --git a/go.mod b/go.mod
index 611debc..19bf822 100644
--- a/go.mod
+++ b/go.mod
@@ -1,5 +1,7 @@
 module go.unistack.org/micro-config-flag/v3
 
-go 1.16
+go 1.18
 
-require go.unistack.org/micro/v3 v3.10.14
+require go.unistack.org/micro/v3 v3.10.16
+
+require github.com/imdario/mergo v0.3.13 // indirect
diff --git a/go.sum b/go.sum
index 3687050..8ff5437 100644
--- a/go.sum
+++ b/go.sum
@@ -2,8 +2,8 @@ github.com/imdario/mergo v0.3.13 h1:lFzP57bqS/wsqKssCGmtLAb8A0wKjLGrve2q3PPVcBk=
 github.com/imdario/mergo v0.3.13/go.mod h1:4lJ1jqUDcsbIECGy0RUJAXNIhg+6ocWgb1ALK2O4oXg=
 github.com/patrickmn/go-cache v2.1.0+incompatible/go.mod h1:3Qf8kWWT7OJRJbdiICTKqZju1ZixQ/KpMGzzAfe6+WQ=
 github.com/silas/dag v0.0.0-20211117232152-9d50aa809f35/go.mod h1:7RTUFBdIRC9nZ7/3RyRNH1bdqIShrDejd1YbLwgPS+I=
-go.unistack.org/micro/v3 v3.10.14 h1:7fgLpwGlCN67twhwtngJDEQvrMkUBDSA5vzZqxIDqNE=
-go.unistack.org/micro/v3 v3.10.14/go.mod h1:uMAc0U/x7dmtICCrblGf0ZLgYegu3VwQAquu+OFCw1Q=
+go.unistack.org/micro/v3 v3.10.16 h1:2er/SKKYbV60M+UuJM4eYCF0MZYAIq/yNUrAbTfgq8Q=
+go.unistack.org/micro/v3 v3.10.16/go.mod h1:uMAc0U/x7dmtICCrblGf0ZLgYegu3VwQAquu+OFCw1Q=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.0/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=