diff --git a/goutils b/goutils
index 21e3d06e..66b3d4cb 160000
--- a/goutils
+++ b/goutils
@@ -1 +1 @@
-Subproject commit 21e3d06e6b8ec57581b8aa0fd44a76a588dce832
+Subproject commit 66b3d4cbebd19b4b5d4c593c7e5e7b62c9d6c9eb
diff --git a/internal/api/v1/file/validate.go b/internal/api/v1/file/validate.go
index 96889570..94e927c7 100644
--- a/internal/api/v1/file/validate.go
+++ b/internal/api/v1/file/validate.go
@@ -57,7 +57,7 @@ func validateFile(fileType FileType, content []byte) gperr.Error {
 		return config.Validate(content)
 	case FileTypeMiddleware:
 		errs := gperr.NewBuilder("middleware errors")
-		middleware.BuildMiddlewaresFromYAML("", content, errs)
+		middleware.BuildMiddlewaresFromYAML("", content, &errs)
 		return errs.Error()
 	}
 	return provider.Validate(content)
diff --git a/internal/net/gphttp/middleware/cidr_whitelist_test.go b/internal/net/gphttp/middleware/cidr_whitelist_test.go
index 9de55033..c7e45e8f 100644
--- a/internal/net/gphttp/middleware/cidr_whitelist_test.go
+++ b/internal/net/gphttp/middleware/cidr_whitelist_test.go
@@ -62,7 +62,7 @@ func TestCIDRWhitelistValidation(t *testing.T) {
 
 func TestCIDRWhitelist(t *testing.T) {
 	errs := gperr.NewBuilder("")
-	mids := BuildMiddlewaresFromYAML("", testCIDRWhitelistCompose, errs)
+	mids := BuildMiddlewaresFromYAML("", testCIDRWhitelistCompose, &errs)
 	expect.NoError(t, errs.Error())
 	deny = mids["deny@file"]
 	accept = mids["accept@file"]
diff --git a/internal/net/gphttp/middleware/middleware_builder_test.go b/internal/net/gphttp/middleware/middleware_builder_test.go
index 2233fe3c..16a4e26a 100644
--- a/internal/net/gphttp/middleware/middleware_builder_test.go
+++ b/internal/net/gphttp/middleware/middleware_builder_test.go
@@ -14,7 +14,7 @@ var testMiddlewareCompose []byte
 
 func TestBuild(t *testing.T) {
 	errs := gperr.NewBuilder("")
-	middlewares := BuildMiddlewaresFromYAML("", testMiddlewareCompose, errs)
+	middlewares := BuildMiddlewaresFromYAML("", testMiddlewareCompose, &errs)
 	expect.NoError(t, errs.Error())
 	expect.Must(json.MarshalIndent(middlewares, "", "  "))
 	// t.Log(string(data))
diff --git a/internal/net/gphttp/middleware/middlewares.go b/internal/net/gphttp/middleware/middlewares.go
index 7360f7f7..571d5e1d 100644
--- a/internal/net/gphttp/middleware/middlewares.go
+++ b/internal/net/gphttp/middleware/middlewares.go
@@ -73,7 +73,7 @@ func LoadComposeFiles() {
 	}
 	for _, defFile := range middlewareDefs {
 		voidErrs := gperr.NewBuilder("") // ignore these errors, will be added in next step
-		mws := BuildMiddlewaresFromComposeFile(defFile, voidErrs)
+		mws := BuildMiddlewaresFromComposeFile(defFile, &voidErrs)
 		if len(mws) == 0 {
 			continue
 		}
@@ -92,7 +92,7 @@ func LoadComposeFiles() {
 	}
 	// build again to resolve cross references
 	for _, defFile := range middlewareDefs {
-		mws := BuildMiddlewaresFromComposeFile(defFile, errs)
+		mws := BuildMiddlewaresFromComposeFile(defFile, &errs)
 		if len(mws) == 0 {
 			continue
 		}
diff --git a/internal/route/provider/event_handler.go b/internal/route/provider/event_handler.go
index eacd5670..23f45ab3 100644
--- a/internal/route/provider/event_handler.go
+++ b/internal/route/provider/event_handler.go
@@ -12,7 +12,7 @@ import (
 type EventHandler struct {
 	provider *Provider
 
-	errs *gperr.Builder
+	errs gperr.Builder
 }
 
 func (p *Provider) newEventHandler() *EventHandler {
diff --git a/internal/route/route.go b/internal/route/route.go
index 04ad1b8d..ee8c8bdd 100644
--- a/internal/route/route.go
+++ b/internal/route/route.go
@@ -219,19 +219,19 @@ func (r *Route) Validate() gperr.Error {
 
 	switch r.Scheme {
 	case route.SchemeFileServer:
-		r.ProxyURL = gperr.Collect(errs, nettypes.ParseURL, "file://"+r.Root)
+		r.ProxyURL = gperr.Collect(&errs, nettypes.ParseURL, "file://"+r.Root)
 		r.Host = ""
 		r.Port.Proxy = 0
 	case route.SchemeHTTP, route.SchemeHTTPS:
 		if r.Port.Listening != 0 {
 			errs.Addf("unexpected listening port for %s scheme", r.Scheme)
 		}
-		r.ProxyURL = gperr.Collect(errs, nettypes.ParseURL, fmt.Sprintf("%s://%s:%d", r.Scheme, r.Host, r.Port.Proxy))
+		r.ProxyURL = gperr.Collect(&errs, nettypes.ParseURL, fmt.Sprintf("%s://%s:%d", r.Scheme, r.Host, r.Port.Proxy))
 	case route.SchemeTCP, route.SchemeUDP:
 		if !r.ShouldExclude() {
-			r.LisURL = gperr.Collect(errs, nettypes.ParseURL, fmt.Sprintf("%s://:%d", r.Scheme, r.Port.Listening))
+			r.LisURL = gperr.Collect(&errs, nettypes.ParseURL, fmt.Sprintf("%s://:%d", r.Scheme, r.Port.Listening))
 		}
-		r.ProxyURL = gperr.Collect(errs, nettypes.ParseURL, fmt.Sprintf("%s://%s:%d", r.Scheme, r.Host, r.Port.Proxy))
+		r.ProxyURL = gperr.Collect(&errs, nettypes.ParseURL, fmt.Sprintf("%s://%s:%d", r.Scheme, r.Host, r.Port.Proxy))
 	}
 
 	if !r.UseHealthCheck() && (r.UseLoadBalance() || r.UseIdleWatcher()) {
diff --git a/internal/types/docker.go b/internal/types/docker.go
index a7bbc34c..89b32e11 100644
--- a/internal/types/docker.go
+++ b/internal/types/docker.go
@@ -54,21 +54,15 @@ type (
 	} // @name ContainerImage
 
 	ContainerError struct {
-		errs *gperr.Builder
+		errs gperr.Builder
 	}
 )
 
 func (e *ContainerError) Add(err error) {
-	if e.errs == nil {
-		e.errs = gperr.NewBuilder()
-	}
 	e.errs.Add(err)
 }
 
 func (e *ContainerError) Error() string {
-	if e.errs == nil {
-		return "<niL>"
-	}
 	return e.errs.String()
 }
 
@@ -77,6 +71,6 @@ func (e *ContainerError) Unwrap() error {
 }
 
 func (e *ContainerError) MarshalJSON() ([]byte, error) {
-	err := e.errs.Error().(interface{ Plain() []byte })
+	err := e.errs.Error().(gperr.PlainError)
 	return sonic.Marshal(string(err.Plain()))
 }