diff --git a/.golangci.yml b/.golangci.yml
index 7d65a80..7f37cca 100644
--- a/.golangci.yml
+++ b/.golangci.yml
@@ -108,6 +108,7 @@ linters:
     - prealloc # Too many false-positive.
     - makezero # Not relevant
     - dupl # Too strict
+    - gci # I don't care
     - gosec # Too strict
     - gochecknoinits
     - gochecknoglobals
diff --git a/internal/api/v1/query/query.go b/internal/api/v1/query/query.go
index 7757004..7b59772 100644
--- a/internal/api/v1/query/query.go
+++ b/internal/api/v1/query/query.go
@@ -14,7 +14,7 @@ import (
 )
 
 func ReloadServer() E.Error {
-	resp, err := U.Post(fmt.Sprintf("%s/v1/reload", common.APIHTTPURL), "", nil)
+	resp, err := U.Post(common.APIHTTPURL+"/v1/reload", "", nil)
 	if err != nil {
 		return E.From(err)
 	}
diff --git a/internal/config/query.go b/internal/config/query.go
index 8933cf3..99131cb 100644
--- a/internal/config/query.go
+++ b/internal/config/query.go
@@ -69,17 +69,18 @@ func HomepageConfig() homepage.Config {
 			)
 		}
 
-		if entry.IsDocker(r) {
+		switch {
+		case entry.IsDocker(r):
 			if item.Category == "" {
 				item.Category = "Docker"
 			}
 			item.SourceType = string(proxy.ProviderTypeDocker)
-		} else if entry.UseLoadBalance(r) {
+		case entry.UseLoadBalance(r):
 			if item.Category == "" {
 				item.Category = "Load-balanced"
 			}
 			item.SourceType = "loadbalancer"
-		} else {
+		default:
 			if item.Category == "" {
 				item.Category = "Others"
 			}
diff --git a/internal/docker/client.go b/internal/docker/client.go
index f1ecf5b..f3b176f 100644
--- a/internal/docker/client.go
+++ b/internal/docker/client.go
@@ -52,13 +52,10 @@ func (c *SharedClient) Connected() bool {
 }
 
 // if the client is still referenced, this is no-op.
-func (c *SharedClient) Close() error {
-	if !c.Connected() {
-		return nil
+func (c *SharedClient) Close() {
+	if c.Connected() {
+		c.refCount.Sub()
 	}
-
-	c.refCount.Sub()
-	return nil
 }
 
 // ConnectClient creates a new Docker client connection to the specified host.
@@ -115,7 +112,6 @@ func ConnectClient(host string) (Client, error) {
 	}
 
 	client, err := client.NewClientWithOpts(opt...)
-
 	if err != nil {
 		return nil, err
 	}
diff --git a/internal/docker/idlewatcher/loading_page.go b/internal/docker/idlewatcher/loading_page.go
index d545c9c..80913c7 100644
--- a/internal/docker/idlewatcher/loading_page.go
+++ b/internal/docker/idlewatcher/loading_page.go
@@ -3,7 +3,6 @@ package idlewatcher
 import (
 	"bytes"
 	_ "embed"
-	"fmt"
 	"strings"
 	"text/template"
 
@@ -21,7 +20,7 @@ var loadingPage []byte
 var loadingPageTmpl = template.Must(template.New("loading_page").Parse(string(loadingPage)))
 
 func (w *Watcher) makeLoadingPageBody() []byte {
-	msg := fmt.Sprintf("%s is starting...", w.ContainerName)
+	msg := w.ContainerName + " is starting..."
 
 	data := new(templateData)
 	data.CheckRedirectHeader = common.HeaderCheckRedirect
diff --git a/internal/docker/idlewatcher/waker.go b/internal/docker/idlewatcher/waker.go
index 6fda047..ea5fed7 100644
--- a/internal/docker/idlewatcher/waker.go
+++ b/internal/docker/idlewatcher/waker.go
@@ -45,17 +45,18 @@ func newWaker(providerSubTask task.Task, entry entry.Entry, rp *gphttp.ReversePr
 		return nil, E.Errorf("register watcher: %w", err)
 	}
 
-	if rp != nil {
+	switch {
+	case rp != nil:
 		waker.hc = health.NewHTTPHealthChecker(entry.TargetURL(), hcCfg, rp.Transport)
-	} else if stream != nil {
+	case stream != nil:
 		waker.hc = health.NewRawHealthChecker(entry.TargetURL(), hcCfg)
-	} else {
+	default:
 		panic("both nil")
 	}
 	return watcher, nil
 }
 
-// lifetime should follow route provider
+// lifetime should follow route provider.
 func NewHTTPWaker(providerSubTask task.Task, entry entry.Entry, rp *gphttp.ReverseProxy) (Waker, E.Error) {
 	return newWaker(providerSubTask, entry, rp, nil)
 }
diff --git a/internal/docker/idlewatcher/waker_stream.go b/internal/docker/idlewatcher/waker_stream.go
index 5cd648b..f1ade45 100644
--- a/internal/docker/idlewatcher/waker_stream.go
+++ b/internal/docker/idlewatcher/waker_stream.go
@@ -28,7 +28,7 @@ func (w *Watcher) Accept() (conn types.StreamConn, err error) {
 		return
 	}
 	if wakeErr := w.wakeFromStream(); wakeErr != nil {
-		w.WakeError(wakeErr).Msg("error waking from stream")
+		w.WakeError(wakeErr)
 	}
 	return
 }
@@ -58,7 +58,7 @@ func (w *Watcher) wakeFromStream() error {
 	wakeErr := w.wakeIfStopped()
 	if wakeErr != nil {
 		wakeErr = fmt.Errorf("%s failed: %w", w.String(), wakeErr)
-		w.WakeError(wakeErr).Msg("wake failed")
+		w.WakeError(wakeErr)
 		return wakeErr
 	}
 
diff --git a/internal/docker/idlewatcher/watcher.go b/internal/docker/idlewatcher/watcher.go
index d23502d..69593c2 100644
--- a/internal/docker/idlewatcher/watcher.go
+++ b/internal/docker/idlewatcher/watcher.go
@@ -17,7 +17,6 @@ import (
 	U "github.com/yusing/go-proxy/internal/utils"
 	F "github.com/yusing/go-proxy/internal/utils/functional"
 	"github.com/yusing/go-proxy/internal/watcher"
-	W "github.com/yusing/go-proxy/internal/watcher"
 	"github.com/yusing/go-proxy/internal/watcher/events"
 )
 
@@ -108,8 +107,8 @@ func (w *Watcher) WakeTrace() *zerolog.Event {
 	return w.Trace().Str("action", "wake")
 }
 
-func (w *Watcher) WakeError(err error) *zerolog.Event {
-	return w.Err(err).Str("action", "wake")
+func (w *Watcher) WakeError(err error) {
+	w.Err(err).Str("action", "wake").Msg("error")
 }
 
 func (w *Watcher) LogReason(action, reason string) {
@@ -204,17 +203,17 @@ func (w *Watcher) resetIdleTimer() {
 
 func (w *Watcher) getEventCh(dockerWatcher watcher.DockerWatcher) (eventTask task.Task, eventCh <-chan events.Event, errCh <-chan E.Error) {
 	eventTask = w.task.Subtask("docker event watcher")
-	eventCh, errCh = dockerWatcher.EventsWithOptions(eventTask.Context(), W.DockerListOptions{
-		Filters: W.NewDockerFilter(
-			W.DockerFilterContainer,
-			W.DockerFilterContainerNameID(w.ContainerID),
-			W.DockerFilterStart,
-			W.DockerFilterStop,
-			W.DockerFilterDie,
-			W.DockerFilterKill,
-			W.DockerFilterDestroy,
-			W.DockerFilterPause,
-			W.DockerFilterUnpause,
+	eventCh, errCh = dockerWatcher.EventsWithOptions(eventTask.Context(), watcher.DockerListOptions{
+		Filters: watcher.NewDockerFilter(
+			watcher.DockerFilterContainer,
+			watcher.DockerFilterContainerNameID(w.ContainerID),
+			watcher.DockerFilterStart,
+			watcher.DockerFilterStop,
+			watcher.DockerFilterDie,
+			watcher.DockerFilterKill,
+			watcher.DockerFilterDestroy,
+			watcher.DockerFilterPause,
+			watcher.DockerFilterUnpause,
 		),
 	})
 	return
@@ -230,9 +229,9 @@ func (w *Watcher) getEventCh(dockerWatcher watcher.DockerWatcher) (eventTask tas
 // stop method.
 //
 // it exits only if the context is canceled, the container is destroyed,
-// errors occured on docker client, or route provider died (mainly caused by config reload).
+// errors occurred on docker client, or route provider died (mainly caused by config reload).
 func (w *Watcher) watchUntilDestroy() (returnCause error) {
-	dockerWatcher := W.NewDockerWatcherWithClient(w.client)
+	dockerWatcher := watcher.NewDockerWatcherWithClient(w.client)
 	eventTask, dockerEventCh, dockerEventErrCh := w.getEventCh(dockerWatcher)
 	defer eventTask.Finish("stopped")
 
@@ -279,9 +278,13 @@ func (w *Watcher) watchUntilDestroy() (returnCause error) {
 		case <-w.ticker.C:
 			w.ticker.Stop()
 			if w.ContainerRunning {
-				if err := w.stopByMethod(); err != nil && !errors.Is(err, context.Canceled) {
+				err := w.stopByMethod()
+				switch {
+				case errors.Is(err, context.Canceled):
+					continue
+				case err != nil:
 					w.Err(err).Msgf("container stop with method %q failed", w.StopMethod)
-				} else {
+				default:
 					w.LogReason("container stopped", "idle timeout")
 				}
 			}
diff --git a/internal/error/builder.go b/internal/error/builder.go
index 12aa474..80681c1 100644
--- a/internal/error/builder.go
+++ b/internal/error/builder.go
@@ -27,26 +27,31 @@ func (b *Builder) HasError() bool {
 	return len(b.errs) > 0
 }
 
-func (b *Builder) Error() Error {
+func (b *Builder) error() Error {
 	if !b.HasError() {
 		return nil
 	}
-	if len(b.errs) == 1 {
-		return From(b.errs[0])
-	}
 	return &nestedError{Err: New(b.about), Extras: b.errs}
 }
 
+func (b *Builder) Error() Error {
+	if len(b.errs) == 1 {
+		return From(b.errs[0])
+	}
+	return b.error()
+}
+
 func (b *Builder) String() string {
-	if !b.HasError() {
+	err := b.error()
+	if err == nil {
 		return ""
 	}
-	return (&nestedError{Err: New(b.about), Extras: b.errs}).Error()
+	return err.Error()
 }
 
 // Add adds an error to the Builder.
 //
-// adding nil is no-op,
+// adding nil is no-op.
 func (b *Builder) Add(err error) *Builder {
 	if err == nil {
 		return b
@@ -90,6 +95,21 @@ func (b *Builder) Addf(format string, args ...any) *Builder {
 	return b
 }
 
+func (b *Builder) AddFrom(other *Builder, flatten bool) *Builder {
+	if other == nil || !other.HasError() {
+		return b
+	}
+
+	b.Lock()
+	defer b.Unlock()
+	if flatten {
+		b.errs = append(b.errs, other.errs...)
+	} else {
+		b.errs = append(b.errs, other.error())
+	}
+	return b
+}
+
 func (b *Builder) AddRange(errs ...error) *Builder {
 	b.Lock()
 	defer b.Unlock()
diff --git a/internal/error/error.go b/internal/error/error.go
index e584653..5e744ba 100644
--- a/internal/error/error.go
+++ b/internal/error/error.go
@@ -22,7 +22,7 @@ type Error interface {
 	Subjectf(format string, args ...any) Error
 }
 
-// this makes JSON marshalling work,
+// this makes JSON marshaling work,
 // as the builtin one doesn't.
 type errStr string
 
diff --git a/internal/logging/logging.go b/internal/logging/logging.go
index 664ea4a..a77c413 100644
--- a/internal/logging/logging.go
+++ b/internal/logging/logging.go
@@ -15,13 +15,14 @@ func init() {
 	var level zerolog.Level
 	var exclude []string
 
-	if common.IsTrace {
+	switch {
+	case common.IsTrace:
 		timeFmt = "04:05"
 		level = zerolog.TraceLevel
-	} else if common.IsDebug {
+	case common.IsDebug:
 		timeFmt = "01-02 15:04"
 		level = zerolog.DebugLevel
-	} else {
+	default:
 		timeFmt = "01-02 15:04"
 		level = zerolog.InfoLevel
 		exclude = []string{"module"}
diff --git a/internal/net/http/content_type.go b/internal/net/http/content_type.go
index 59b021d..3b4be65 100644
--- a/internal/net/http/content_type.go
+++ b/internal/net/http/content_type.go
@@ -5,8 +5,10 @@ import (
 	"net/http"
 )
 
-type ContentType string
-type AcceptContentType []ContentType
+type (
+	ContentType       string
+	AcceptContentType []ContentType
+)
 
 func GetContentType(h http.Header) ContentType {
 	ct := h.Get("Content-Type")
diff --git a/internal/net/http/loadbalancer/loadbalancer.go b/internal/net/http/loadbalancer/loadbalancer.go
index 4812116..edda918 100644
--- a/internal/net/http/loadbalancer/loadbalancer.go
+++ b/internal/net/http/loadbalancer/loadbalancer.go
@@ -55,7 +55,6 @@ func New(cfg *Config) *LoadBalancer {
 		Logger: logger.With().Str("name", cfg.Link).Logger(),
 		Config: new(Config),
 		pool:   newPool(),
-		task:   task.DummyTask(),
 	}
 	lb.UpdateConfigIfNeeded(cfg)
 	return lb
diff --git a/internal/net/http/loadbalancer/mode.go b/internal/net/http/loadbalancer/mode.go
index 919d311..cea093d 100644
--- a/internal/net/http/loadbalancer/mode.go
+++ b/internal/net/http/loadbalancer/mode.go
@@ -1,7 +1,7 @@
 package loadbalancer
 
 import (
-	U "github.com/yusing/go-proxy/internal/utils"
+	"github.com/yusing/go-proxy/internal/utils/strutils"
 )
 
 type Mode string
@@ -14,7 +14,7 @@ const (
 )
 
 func (mode *Mode) ValidateUpdate() bool {
-	switch U.ToLowerNoSnake(string(*mode)) {
+	switch strutils.ToLowerNoSnake(string(*mode)) {
 	case "":
 		return true
 	case string(RoundRobin):
diff --git a/internal/net/http/middleware/cloudflare_real_ip.go b/internal/net/http/middleware/cloudflare_real_ip.go
index f2c5b92..aa82345 100644
--- a/internal/net/http/middleware/cloudflare_real_ip.go
+++ b/internal/net/http/middleware/cloudflare_real_ip.go
@@ -109,9 +109,9 @@ func fetchUpdateCFIPRange(endpoint string, cfCIDRs []*types.CIDR) error {
 		_, cidr, err := net.ParseCIDR(line)
 		if err != nil {
 			return fmt.Errorf("cloudflare responeded an invalid CIDR: %s", line)
-		} else {
-			cfCIDRs = append(cfCIDRs, (*types.CIDR)(cidr))
 		}
+
+		cfCIDRs = append(cfCIDRs, (*types.CIDR)(cidr))
 	}
 
 	return nil
diff --git a/internal/net/http/middleware/errorpage/error_page.go b/internal/net/http/middleware/errorpage/error_page.go
index 7f63d5d..7226f67 100644
--- a/internal/net/http/middleware/errorpage/error_page.go
+++ b/internal/net/http/middleware/errorpage/error_page.go
@@ -19,24 +19,33 @@ import (
 const errPagesBasePath = common.ErrorPagesBasePath
 
 var (
+	setupMu        sync.Mutex
 	dirWatcher     W.Watcher
 	fileContentMap = F.NewMapOf[string, []byte]()
 )
 
-var setup = sync.OnceFunc(func() {
+func setup() {
+	setupMu.Lock()
+	defer setupMu.Unlock()
+
+	if dirWatcher != nil {
+		return
+	}
+
 	task := task.GlobalTask("error page")
 	dirWatcher = W.NewDirectoryWatcher(task.Subtask("dir watcher"), errPagesBasePath)
 	loadContent()
 	go watchDir(task)
-})
+}
 
 func GetStaticFile(filename string) ([]byte, bool) {
+	setup()
 	return fileContentMap.Load(filename)
 }
 
 // try <statusCode>.html -> 404.html -> not ok.
 func GetErrorPageByStatus(statusCode int) (content []byte, ok bool) {
-	content, ok = fileContentMap.Load(fmt.Sprintf("%d.html", statusCode))
+	content, ok = GetStaticFile(fmt.Sprintf("%d.html", statusCode))
 	if !ok && statusCode != 404 {
 		return fileContentMap.Load("404.html")
 	}
diff --git a/internal/net/http/middleware/middlewares.go b/internal/net/http/middleware/middlewares.go
index 4ff3699..111bd63 100644
--- a/internal/net/http/middleware/middlewares.go
+++ b/internal/net/http/middleware/middlewares.go
@@ -9,7 +9,6 @@ import (
 	"github.com/yusing/go-proxy/internal/common"
 	E "github.com/yusing/go-proxy/internal/error"
 	"github.com/yusing/go-proxy/internal/utils"
-	U "github.com/yusing/go-proxy/internal/utils"
 	"github.com/yusing/go-proxy/internal/utils/strutils"
 )
 
@@ -21,7 +20,7 @@ var (
 )
 
 func Get(name string) (*Middleware, Error) {
-	middleware, ok := allMiddlewares[U.ToLowerNoSnake(name)]
+	middleware, ok := allMiddlewares[strutils.ToLowerNoSnake(name)]
 	if !ok {
 		return nil, ErrUnknownMiddleware.
 			Subject(name).
@@ -34,7 +33,7 @@ func All() map[string]*Middleware {
 	return allMiddlewares
 }
 
-// initialize middleware names and label parsers
+// initialize middleware names and label parsers.
 func init() {
 	allMiddlewares = map[string]*Middleware{
 		"setxforwarded":    SetXForwarded,
@@ -67,7 +66,7 @@ func init() {
 
 func LoadComposeFiles() {
 	errs := E.NewBuilder("middleware compile errors")
-	middlewareDefs, err := U.ListFiles(common.MiddlewareComposeBasePath, 0)
+	middlewareDefs, err := utils.ListFiles(common.MiddlewareComposeBasePath, 0)
 	if err != nil {
 		logger.Err(err).Msg("failed to list middleware definitions")
 		return
@@ -82,7 +81,7 @@ func LoadComposeFiles() {
 				errs.Add(ErrDuplicatedMiddleware.Subject(name))
 				continue
 			}
-			allMiddlewares[U.ToLowerNoSnake(name)] = m
+			allMiddlewares[strutils.ToLowerNoSnake(name)] = m
 			logger.Info().
 				Str("name", name).
 				Str("src", path.Base(defFile)).
diff --git a/internal/net/http/middleware/trace.go b/internal/net/http/middleware/trace.go
index 2b444f3..b1ad036 100644
--- a/internal/net/http/middleware/trace.go
+++ b/internal/net/http/middleware/trace.go
@@ -22,8 +22,10 @@ type Trace struct {
 
 type Traces []*Trace
 
-var traces = Traces{}
-var tracesMu sync.Mutex
+var (
+	traces   = make(Traces, 0)
+	tracesMu sync.Mutex
+)
 
 const MaxTraceNum = 100
 
diff --git a/internal/net/http/modify_response_writer.go b/internal/net/http/modify_response_writer.go
index a7a82c2..6a8122f 100644
--- a/internal/net/http/modify_response_writer.go
+++ b/internal/net/http/modify_response_writer.go
@@ -10,18 +10,20 @@ import (
 	"net/http"
 )
 
-type ModifyResponseFunc func(*http.Response) error
-type ModifyResponseWriter struct {
-	w http.ResponseWriter
-	r *http.Request
+type (
+	ModifyResponseFunc   func(*http.Response) error
+	ModifyResponseWriter struct {
+		w http.ResponseWriter
+		r *http.Request
 
-	headerSent bool
-	code       int
+		headerSent bool
+		code       int
 
-	modifier    ModifyResponseFunc
-	modified    bool
-	modifierErr error
-}
+		modifier    ModifyResponseFunc
+		modified    bool
+		modifierErr error
+	}
+)
 
 func NewModifyResponseWriter(w http.ResponseWriter, r *http.Request, f ModifyResponseFunc) *ModifyResponseWriter {
 	return &ModifyResponseWriter{
diff --git a/internal/notif/dispatcher.go b/internal/notif/dispatcher.go
index 79dcc82..c6d390d 100644
--- a/internal/notif/dispatcher.go
+++ b/internal/notif/dispatcher.go
@@ -53,15 +53,15 @@ func RegisterProvider(configSubTask task.Task, cfg ProviderConfig) (Provider, er
 			Subject(name).
 			Withf(strutils.DoYouMean(utils.NearestField(name, Providers)))
 	}
-	if provider, err := createFunc(cfg); err != nil {
-		return nil, err
-	} else {
+
+	provider, err := createFunc(cfg)
+	if err == nil {
 		dispatcher.providers.Add(provider)
 		configSubTask.OnCancel("remove provider", func() {
 			dispatcher.providers.Remove(provider)
 		})
-		return provider, nil
 	}
+	return provider, err
 }
 
 func (disp *Dispatcher) start() {
diff --git a/internal/proxy/entry/reverse_proxy.go b/internal/proxy/entry/reverse_proxy.go
index 976dde3..fc9d5f4 100644
--- a/internal/proxy/entry/reverse_proxy.go
+++ b/internal/proxy/entry/reverse_proxy.go
@@ -68,7 +68,7 @@ func validateRPEntry(m *RawEntry, s fields.Scheme, errs *E.Builder) *ReverseProx
 	port := E.Collect(errs, fields.ValidatePort, m.Port)
 	pathPats := E.Collect(errs, fields.ValidatePathPatterns, m.PathPatterns)
 	url := E.Collect(errs, url.Parse, fmt.Sprintf("%s://%s:%d", s, host, port))
-	iwCfg := E.Collect(errs, idlewatcher.ValidateConfig, m.Container)
+	iwCfg := E.Collect(errs, idlewatcher.ValidateConfig, cont)
 
 	if errs.HasError() {
 		return nil
diff --git a/internal/proxy/entry/stream.go b/internal/proxy/entry/stream.go
index 5ffabe8..08597d8 100644
--- a/internal/proxy/entry/stream.go
+++ b/internal/proxy/entry/stream.go
@@ -61,7 +61,7 @@ func validateStreamEntry(m *RawEntry, errs *E.Builder) *StreamEntry {
 	port := E.Collect(errs, fields.ValidateStreamPort, m.Port)
 	scheme := E.Collect(errs, fields.ValidateStreamScheme, m.Scheme)
 	url := E.Collect(errs, net.ParseURL, fmt.Sprintf("%s://%s:%d", scheme.ListeningScheme, host, port.ListeningPort))
-	idleWatcherCfg := E.Collect(errs, idlewatcher.ValidateConfig, m.Container)
+	idleWatcherCfg := E.Collect(errs, idlewatcher.ValidateConfig, cont)
 
 	if errs.HasError() {
 		return nil
diff --git a/internal/route/http.go b/internal/route/http.go
index 46edeb8..5230665 100755
--- a/internal/route/http.go
+++ b/internal/route/http.go
@@ -89,7 +89,6 @@ func NewHTTPRoute(entry *entry.ReverseProxyEntry) (impl, E.Error) {
 	r := &HTTPRoute{
 		ReverseProxyEntry: entry,
 		rp:                rp,
-		task:              task.DummyTask(),
 		l: logger.With().
 			Str("type", string(entry.Scheme)).
 			Str("name", string(entry.Alias)).
diff --git a/internal/route/provider/event_handler.go b/internal/route/provider/event_handler.go
index 6c990ce..9a67373 100644
--- a/internal/route/provider/event_handler.go
+++ b/internal/route/provider/event_handler.go
@@ -18,9 +18,9 @@ type EventHandler struct {
 	updated *E.Builder
 }
 
-func (provider *Provider) newEventHandler() *EventHandler {
+func (p *Provider) newEventHandler() *EventHandler {
 	return &EventHandler{
-		provider: provider,
+		provider: p,
 		errs:     E.NewBuilder("event errors"),
 		added:    E.NewBuilder("added"),
 		removed:  E.NewBuilder("removed"),
@@ -60,11 +60,12 @@ func (handler *EventHandler) Handle(parent task.Task, events []watcher.Event) {
 
 	oldRoutes.RangeAll(func(k string, oldr *route.Route) {
 		newr, ok := newRoutes.Load(k)
-		if !ok {
+		switch {
+		case !ok:
 			handler.Remove(oldr)
-		} else if handler.matchAny(events, newr) {
+		case handler.matchAny(events, newr):
 			handler.Update(parent, oldr, newr)
-		} else if entry.ShouldNotServe(newr) {
+		case entry.ShouldNotServe(newr):
 			handler.Remove(oldr)
 		}
 	})
@@ -122,11 +123,11 @@ func (handler *EventHandler) Update(parent task.Task, oldRoute *route.Route, new
 }
 
 func (handler *EventHandler) Log() {
-	results := E.NewBuilder("event occured")
-	results.Add(handler.added.Error())
-	results.Add(handler.removed.Error())
-	results.Add(handler.updated.Error())
-	results.Add(handler.errs.Error())
+	results := E.NewBuilder("event occurred")
+	results.AddFrom(handler.added, false)
+	results.AddFrom(handler.removed, false)
+	results.AddFrom(handler.updated, false)
+	results.AddFrom(handler.errs, false)
 	if result := results.String(); result != "" {
 		handler.provider.Logger().Info().Msg(result)
 	}
diff --git a/internal/route/provider/provider.go b/internal/route/provider/provider.go
index e6cb01e..0c87caf 100644
--- a/internal/route/provider/provider.go
+++ b/internal/route/provider/provider.go
@@ -45,9 +45,7 @@ const (
 	providerEventFlushInterval = 300 * time.Millisecond
 )
 
-var (
-	ErrEmptyProviderName = errors.New("empty provider name")
-)
+var ErrEmptyProviderName = errors.New("empty provider name")
 
 func newProvider(name string, t ProviderType) *Provider {
 	return &Provider{
@@ -109,12 +107,11 @@ func (p *Provider) startRoute(parent task.Task, r *R.Route) E.Error {
 		p.routes.Delete(r.Entry.Alias)
 		subtask.Finish(err) // just to ensure
 		return err.Subject(r.Entry.Alias)
-	} else {
-		p.routes.Store(r.Entry.Alias, r)
-		subtask.OnFinished("del from provider", func() {
-			p.routes.Delete(r.Entry.Alias)
-		})
 	}
+	p.routes.Store(r.Entry.Alias, r)
+	subtask.OnFinished("del from provider", func() {
+		p.routes.Delete(r.Entry.Alias)
+	})
 	return nil
 }
 
diff --git a/internal/route/route.go b/internal/route/route.go
index 8cace61..fe0f800 100755
--- a/internal/route/route.go
+++ b/internal/route/route.go
@@ -80,11 +80,12 @@ func FromEntries(entries entry.RawEntries) (Routes, E.Error) {
 	entries.RangeAllParallel(func(alias string, en *entry.RawEntry) {
 		en.Alias = alias
 		r, err := NewRoute(en)
-		if err != nil {
+		switch {
+		case err != nil:
 			b.Add(err.Subject(alias))
-		} else if entry.ShouldNotServe(r) {
+		case entry.ShouldNotServe(r):
 			return
-		} else {
+		default:
 			routes.Store(alias, r)
 		}
 	})
diff --git a/internal/route/stream.go b/internal/route/stream.go
index cf22ff6..c288a4b 100755
--- a/internal/route/stream.go
+++ b/internal/route/stream.go
@@ -44,7 +44,6 @@ func NewStreamRoute(entry *entry.StreamEntry) (impl, E.Error) {
 	}
 	return &StreamRoute{
 		StreamEntry: entry,
-		task:        task.DummyTask(),
 		l: logger.With().
 			Str("type", string(entry.Scheme.ListeningScheme)).
 			Str("name", entry.TargetName()).
diff --git a/internal/server/server.go b/internal/server/server.go
index f6f4bf5..a6caae4 100644
--- a/internal/server/server.go
+++ b/internal/server/server.go
@@ -6,7 +6,6 @@ import (
 	"errors"
 	"io"
 	"log"
-
 	"net/http"
 	"time"
 
diff --git a/internal/utils/io.go b/internal/utils/io.go
index c60ff33..d70e168 100644
--- a/internal/utils/io.go
+++ b/internal/utils/io.go
@@ -102,7 +102,7 @@ func (p BidirectionalPipe) Start() E.Error {
 // Copyright 2009 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // This is a copy of io.Copy with context handling
-// Author: yusing <yusing@6uo.me>
+// Author: yusing <yusing@6uo.me>.
 func Copy(dst *ContextWriter, src *ContextReader) (err error) {
 	size := 32 * 1024
 	if l, ok := src.Reader.(*io.LimitedReader); ok && int64(size) > l.N {
diff --git a/internal/utils/nearest_field.go b/internal/utils/nearest_field.go
index 01cae8b..9919dd4 100644
--- a/internal/utils/nearest_field.go
+++ b/internal/utils/nearest_field.go
@@ -18,9 +18,10 @@ func NearestField(input string, s any) string {
 		if t.Kind() == reflect.Ptr {
 			t = t.Elem()
 		}
-		if t.Kind() == reflect.Struct {
+		switch t.Kind() {
+		case reflect.Struct:
 			fields = make([]string, 0)
-			for i := 0; i < t.NumField(); i++ {
+			for i := range t.NumField() {
 				jsonTag, ok := t.Field(i).Tag.Lookup("json")
 				if ok {
 					fields = append(fields, jsonTag)
@@ -28,13 +29,13 @@ func NearestField(input string, s any) string {
 					fields = append(fields, t.Field(i).Name)
 				}
 			}
-		} else if t.Kind() == reflect.Map {
+		case reflect.Map:
 			keys := reflect.ValueOf(s).MapKeys()
 			fields = make([]string, len(keys))
 			for i, key := range keys {
 				fields[i] = key.String()
 			}
-		} else {
+		default:
 			panic("unsupported type: " + t.String())
 		}
 	}
diff --git a/internal/utils/serialization.go b/internal/utils/serialization.go
index 7ab9ce4..b215068 100644
--- a/internal/utils/serialization.go
+++ b/internal/utils/serialization.go
@@ -27,7 +27,7 @@ var (
 	ErrInvalidType           = E.New("invalid type")
 	ErrNilValue              = E.New("nil")
 	ErrUnsettable            = E.New("unsettable")
-	ErrUnsupportedConvertion = E.New("unsupported convertion")
+	ErrUnsupportedConversion = E.New("unsupported conversion")
 	ErrMapMissingColon       = E.New("map missing colon")
 	ErrMapTooManyColons      = E.New("map too many colons")
 	ErrUnknownField          = E.New("unknown field")
@@ -176,10 +176,10 @@ func Deserialize(src SerializedObject, dst any) E.Error {
 	case reflect.Struct:
 		mapping := make(map[string]reflect.Value)
 		for _, field := range reflect.VisibleFields(dstT) {
-			mapping[ToLowerNoSnake(field.Name)] = dstV.FieldByName(field.Name)
+			mapping[strutils.ToLowerNoSnake(field.Name)] = dstV.FieldByName(field.Name)
 		}
 		for k, v := range src {
-			if field, ok := mapping[ToLowerNoSnake(k)]; ok {
+			if field, ok := mapping[strutils.ToLowerNoSnake(k)]; ok {
 				err := Convert(reflect.ValueOf(v), field)
 				if err != nil {
 					errs.Add(err.Subject(k))
@@ -199,11 +199,11 @@ func Deserialize(src SerializedObject, dst any) E.Error {
 			if err != nil {
 				errs.Add(err.Subject(k))
 			}
-			dstV.SetMapIndex(reflect.ValueOf(ToLowerNoSnake(k)), tmp)
+			dstV.SetMapIndex(reflect.ValueOf(strutils.ToLowerNoSnake(k)), tmp)
 		}
 		return errs.Error()
 	default:
-		return ErrUnsupportedConvertion.Subject("deserialize to " + dstT.String())
+		return ErrUnsupportedConversion.Subject("deserialize to " + dstT.String())
 	}
 }
 
@@ -250,12 +250,12 @@ func Convert(src reflect.Value, dst reflect.Value) E.Error {
 	case srcT.Kind() == reflect.Map:
 		obj, ok := src.Interface().(SerializedObject)
 		if !ok {
-			return ErrUnsupportedConvertion.Subject(dstT.String() + " to " + srcT.String())
+			return ErrUnsupportedConversion.Subject(dstT.String() + " to " + srcT.String())
 		}
 		return Deserialize(obj, dst.Addr().Interface())
 	case srcT.Kind() == reflect.Slice:
 		if dstT.Kind() != reflect.Slice {
-			return ErrUnsupportedConvertion.Subject(dstT.String() + " to slice")
+			return ErrUnsupportedConversion.Subject(dstT.String() + " to slice")
 		}
 		newSlice := reflect.MakeSlice(dstT, 0, src.Len())
 		i := 0
@@ -280,7 +280,7 @@ func Convert(src reflect.Value, dst reflect.Value) E.Error {
 	var ok bool
 	// check if (*T).Convertor is implemented
 	if converter, ok = dst.Addr().Interface().(Converter); !ok {
-		return ErrUnsupportedConvertion.Subjectf("%s to %s", srcT, dstT)
+		return ErrUnsupportedConversion.Subjectf("%s to %s", srcT, dstT)
 	}
 
 	return converter.ConvertFrom(src.Interface())
@@ -310,6 +310,7 @@ func ConvertString(src string, dst reflect.Value) (convertible bool, convErr E.E
 		}
 		dst.Set(reflect.ValueOf(d))
 		return
+	default:
 	}
 	// primitive types / simple types
 	switch dst.Kind() {
@@ -392,7 +393,3 @@ func DeserializeJSON(j map[string]string, target any) error {
 	}
 	return json.Unmarshal(data, target)
 }
-
-func ToLowerNoSnake(s string) string {
-	return strings.ToLower(strings.ReplaceAll(s, "_", ""))
-}
diff --git a/internal/utils/strutils/format.go b/internal/utils/strutils/format.go
index c5027fc..db4dea0 100644
--- a/internal/utils/strutils/format.go
+++ b/internal/utils/strutils/format.go
@@ -2,6 +2,7 @@ package strutils
 
 import (
 	"fmt"
+	"strconv"
 	"strings"
 	"time"
 
@@ -57,6 +58,10 @@ func ParseBool(s string) bool {
 	}
 }
 
+func PortString(port uint16) string {
+	return strconv.FormatUint(uint64(port), 10)
+}
+
 func DoYouMean(s string) string {
 	return "Did you mean " + ansi.HighlightGreen + s + ansi.Reset + "?"
 }
diff --git a/internal/utils/strutils/string.go b/internal/utils/strutils/string.go
index a2af3a0..c329f2f 100644
--- a/internal/utils/strutils/string.go
+++ b/internal/utils/strutils/string.go
@@ -2,7 +2,6 @@ package strutils
 
 import (
 	"net/url"
-	"strconv"
 	"strings"
 
 	"golang.org/x/text/cases"
@@ -29,8 +28,8 @@ func ExtractPort(fullURL string) (int, error) {
 	return Atoi(url.Port())
 }
 
-func PortString(port uint16) string {
-	return strconv.FormatUint(uint64(port), 10)
+func ToLowerNoSnake(s string) string {
+	return strings.ToLower(strings.ReplaceAll(s, "_", ""))
 }
 
 func LevenshteinDistance(a, b string) int {
@@ -60,7 +59,7 @@ func LevenshteinDistance(a, b string) int {
 				cost = 1
 			}
 
-			v1[j+1] = min(v1[j]+1, v0[j+1]+1, v0[j]+cost)
+			v1[j+1] = min3(v1[j]+1, v0[j+1]+1, v0[j]+cost)
 		}
 
 		for j := 0; j <= len(b); j++ {
@@ -71,7 +70,7 @@ func LevenshteinDistance(a, b string) int {
 	return v1[len(b)]
 }
 
-func min(a, b, c int) int {
+func min3(a, b, c int) int {
 	if a < b && a < c {
 		return a
 	}
diff --git a/internal/watcher/health/monitor.go b/internal/watcher/health/monitor.go
index 281ad84..9790755 100644
--- a/internal/watcher/health/monitor.go
+++ b/internal/watcher/health/monitor.go
@@ -37,7 +37,6 @@ func newMonitor(url types.URL, config *HealthCheckConfig, healthCheckFunc Health
 		config:      config,
 		checkHealth: healthCheckFunc,
 		startTime:   time.Now(),
-		task:        task.DummyTask(),
 	}
 	mon.url.Store(url)
 	mon.status.Store(StatusHealthy)