diff --git a/cmd/sower/main.go b/cmd/sower/main.go
index d7b5881..6c8b713 100644
--- a/cmd/sower/main.go
+++ b/cmd/sower/main.go
@@ -18,7 +18,7 @@ import (
 	"github.com/cristalhq/aconfig/aconfigyaml"
 	"github.com/miekg/dns"
 	"github.com/pkg/errors"
-	"github.com/wweir/deferlog/log"
+	"github.com/sower-proxy/deferlog/log"
 	"github.com/wweir/sower/router"
 )
 
diff --git a/cmd/sower/proxy.go b/cmd/sower/proxy.go
index b647d8b..1d095bd 100644
--- a/cmd/sower/proxy.go
+++ b/cmd/sower/proxy.go
@@ -8,14 +8,14 @@ import (
 	"time"
 
 	"github.com/pkg/errors"
-	"github.com/wweir/deferlog/log"
-	"github.com/wweir/sower/pkg/teeconn"
+	"github.com/sower-proxy/conns/relay"
+	"github.com/sower-proxy/conns/teeconn"
+	"github.com/sower-proxy/deferlog/log"
 	"github.com/wweir/sower/router"
 	"github.com/wweir/sower/transport"
 	"github.com/wweir/sower/transport/socks5"
 	"github.com/wweir/sower/transport/sower"
 	"github.com/wweir/sower/transport/trojan"
-	"github.com/wweir/sower/util"
 )
 
 func GenProxyDial(proxyType, proxyHost, proxyPassword string) router.ProxyDialFn {
@@ -97,7 +97,7 @@ func ServeHTTP(ln net.Listener, r *router.Router) {
 	defer rc.Close()
 
 	teeconn.Stop().Reread()
-	util.Relay(teeconn, rc)
+	relay.Relay(teeconn, rc)
 	log.Debug().
 		Str("host", req.Host).
 		Dur("spend", time.Since(start)).
@@ -134,7 +134,7 @@ func ServeHTTPS(ln net.Listener, r *router.Router) {
 	defer rc.Close()
 
 	teeconn.Stop().Reread()
-	util.Relay(teeconn, rc)
+	relay.Relay(teeconn, rc)
 	log.Debug().
 		Str("host", domain).
 		Dur("spend", time.Since(start)).
diff --git a/cmd/sowerd/main.go b/cmd/sowerd/main.go
index cedb2d0..1615f5a 100644
--- a/cmd/sowerd/main.go
+++ b/cmd/sowerd/main.go
@@ -9,12 +9,12 @@ import (
 	"time"
 
 	"github.com/cristalhq/aconfig"
-	"github.com/wweir/deferlog"
-	"github.com/wweir/deferlog/log"
-	"github.com/wweir/sower/pkg/teeconn"
+	"github.com/sower-proxy/conns/relay"
+	"github.com/sower-proxy/conns/teeconn"
+	"github.com/sower-proxy/deferlog"
+	"github.com/sower-proxy/deferlog/log"
 	"github.com/wweir/sower/transport/sower"
 	"github.com/wweir/sower/transport/trojan"
-	"github.com/wweir/sower/util"
 	"golang.org/x/crypto/acme/autocert"
 )
 
@@ -124,7 +124,7 @@ func serve443(ln net.Listener, fakeSite string, sower *sower.Sower, trojan *troj
 	if addr, err = sower.Unwrap(teeconn); err == nil {
 		teeconn.Stop()
 
-		dur, err = util.RelayTo(teeconn, addr.String())
+		dur, err = relay.RelayTo(teeconn, addr.String())
 		return
 	}
 
@@ -133,11 +133,11 @@ func serve443(ln net.Listener, fakeSite string, sower *sower.Sower, trojan *troj
 	if addr, err = trojan.Unwrap(teeconn); err == nil {
 		teeconn.Stop()
 
-		dur, err = util.RelayTo(teeconn, addr.String())
+		dur, err = relay.RelayTo(teeconn, addr.String())
 		return
 	}
 
 	// 3. fallback to fake site
 	teeconn.Stop().Reread()
-	dur, err = util.RelayTo(teeconn, fakeSite)
+	dur, err = relay.RelayTo(teeconn, fakeSite)
 }
diff --git a/go.mod b/go.mod
index 3eaa3c1..d887721 100644
--- a/go.mod
+++ b/go.mod
@@ -12,8 +12,9 @@ require (
 	github.com/miekg/dns v1.1.43
 	github.com/oschwald/geoip2-golang v1.5.0
 	github.com/pkg/errors v0.9.1
-	github.com/ulule/deepcopier v0.0.0-20200430083143-45decc6639b6
-	github.com/wweir/deferlog v1.0.0
+	github.com/sower-proxy/conns v0.0.1
+	github.com/sower-proxy/deferlog v1.0.1
+	github.com/sower-proxy/mem v0.0.1
 	golang.org/x/crypto v0.0.0-20211202192323-5770296d904e
 )
 
@@ -22,6 +23,7 @@ require (
 	github.com/hashicorp/hcl v1.0.0 // indirect
 	github.com/oschwald/maxminddb-golang v1.8.0 // indirect
 	github.com/rs/zerolog v1.26.0 // indirect
+	github.com/ulule/deepcopier v0.0.0-20200430083143-45decc6639b6 // indirect
 	golang.org/x/net v0.0.0-20211112202133-69e39bad7dc2 // indirect
 	golang.org/x/sys v0.0.0-20210809222454-d867a43fc93e // indirect
 	golang.org/x/text v0.3.6 // indirect
diff --git a/go.sum b/go.sum
index 03c3300..b24b269 100644
--- a/go.sum
+++ b/go.sum
@@ -33,14 +33,18 @@ github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZN
 github.com/rs/xid v1.3.0/go.mod h1:trrq9SKmegXys3aeAKXMUTdJsYXVwGY3RLcfgqegfbg=
 github.com/rs/zerolog v1.26.0 h1:ORM4ibhEZeTeQlCojCK2kPz1ogAY4bGs4tD+SaAdGaE=
 github.com/rs/zerolog v1.26.0/go.mod h1:yBiM87lvSqX8h0Ww4sdzNSkVYZ8dL2xjZJG1lAuGZEo=
+github.com/sower-proxy/conns v0.0.1 h1:8tKWQR+nEEH0UBfFSz4M7HAhFFf/o9rQZ/6I0yWjXE8=
+github.com/sower-proxy/conns v0.0.1/go.mod h1:jpifOR3jj9HFTE3wXd6sKdd778ZaRC/zoLKkdtvXNB8=
+github.com/sower-proxy/deferlog v1.0.1 h1:ZRMpB3BOt0tpGiRIPKzg4/1kQ9UGZWgVM3sA1kAmW+c=
+github.com/sower-proxy/deferlog v1.0.1/go.mod h1:wd8Yxz45ZbCgzXEafgDCj7XLlcqYUoEoLyiP1NQOUMk=
+github.com/sower-proxy/mem v0.0.1 h1:z5Mde14Bf+NNP4wbZwQ1noMf5XzEmWH7o05FhfSJEWA=
+github.com/sower-proxy/mem v0.0.1/go.mod h1:/VJ8gxzVmxqKrjSX41Ye0I9ynnueamcjhFIZGwe0/tg=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/ulule/deepcopier v0.0.0-20200430083143-45decc6639b6 h1:TtyC78WMafNW8QFfv3TeP3yWNDG+uxNkk9vOrnDu6JA=
 github.com/ulule/deepcopier v0.0.0-20200430083143-45decc6639b6/go.mod h1:h8272+G2omSmi30fBXiZDMkmHuOgonplfKIKjQWzlfs=
-github.com/wweir/deferlog v1.0.0 h1:rARp+N6FGQeGiN9Ufoty8y8lBchldeOCgmEmPjIV8Ss=
-github.com/wweir/deferlog v1.0.0/go.mod h1:MnYQMIry5XfHBVK/qh1TPMDd/YY4izq3OxboMFXdHrg=
 github.com/yuin/goldmark v1.4.0/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
diff --git a/pkg/mem/mem.go b/pkg/mem/mem.go
deleted file mode 100644
index c101bd0..0000000
--- a/pkg/mem/mem.go
+++ /dev/null
@@ -1,139 +0,0 @@
-package mem
-
-import (
-	"errors"
-	"reflect"
-	"sync"
-	"time"
-
-	"github.com/ulule/deepcopier"
-)
-
-// Data define the type which can speed up by mem cache
-type Data interface {
-	Fulfill(key string) (err error)
-}
-
-// Cache is the definition of cache, be careful of the memory usage
-type Cache struct {
-	old     *sync.Map
-	now     *sync.Map
-	barrier *sync.Map
-	rotate  <-chan time.Time
-	rwmutex *sync.RWMutex
-}
-
-// DefaultCache is default cache for surge
-var DefaultCache = New(time.Minute)
-
-// Remember is a surge, it provides a quite simple way to use cache
-func Remember(dst Data, key string) error {
-	return DefaultCache.Remember(dst, key)
-}
-
-// Delete is a surge, it delete a specified data in DefaultCache
-func Delete(dst Data, key string) {
-	DefaultCache.Delete(dst, key)
-}
-
-// New create a cache entity with a custom expiration time
-func New(rotateInterval time.Duration) *Cache {
-	return &Cache{
-		old:     &sync.Map{},
-		now:     &sync.Map{},
-		barrier: &sync.Map{},
-		rotate:  time.NewTicker(rotateInterval).C,
-		rwmutex: &sync.RWMutex{},
-	}
-}
-
-// Remember automatically save and retrieve data from a cache entity
-func (c *Cache) Remember(dst Data, key string) error {
-	rv := reflect.ValueOf(dst)
-	if rv.Kind() != reflect.Ptr {
-		panic("invalid not pointor type: " + reflect.TypeOf(dst).Name())
-	} else if rv.IsNil() {
-		return errors.New("invalid nil pointor")
-	}
-
-	c.rwmutex.RLock()
-	defer c.rwmutex.RUnlock()
-
-	// rotate logic, rwlock just protect fields in Cache, but not field content.
-	// So that, write lock just take a very short time, and simple read lock is
-	// just an atomic action, do not care the performance
-	select {
-	case <-c.rotate:
-		c.old = c.now
-		c.now = &sync.Map{}
-		c.barrier = &sync.Map{}
-	default:
-	}
-
-	// First: load from cache
-	if val, ok := c.now.Load(key); ok {
-		return deepcopier.Copy(val).To(dst)
-	}
-
-	// Second: load from old cache, or waitting the sigle groutine getting data
-	ch := make(chan struct{})
-	if chVal, ok := c.barrier.LoadOrStore(key, ch); ok {
-		close(ch) // the ch is not used
-
-		if val, ok := c.old.Load(key); ok {
-			return deepcopier.Copy(val).To(dst)
-		}
-
-		// type chan:  wait the sigle groutine getting data
-		// type error: already failed
-		if ch, ok = chVal.(chan struct{}); ok {
-			<-ch
-			if val, ok := c.now.Load(key); ok {
-				return deepcopier.Copy(val).To(dst)
-			}
-		}
-
-		val, _ := c.barrier.Load(key)
-		if err, ok := val.(error); ok {
-			return err
-		}
-
-		panic("new value lost, please report a bug")
-	}
-
-	// Third: getting data from CacheType, maybe from db
-	err := dst.Fulfill(key)
-	if err != nil {
-		c.barrier.Store(key, err)
-		return err
-	}
-
-	c.now.Store(key, dst)
-	close(ch) // broadcast, wakeup all waiting groutine
-
-	return nil
-}
-
-// Delete immediately specified the cached content to expire
-func (c *Cache) Delete(dst Data, key string) {
-	c.rwmutex.Lock()
-	defer c.rwmutex.Unlock()
-
-	c.old.Delete(key)
-	c.now.Delete(key)
-	c.barrier.Store(key, errors.New(key+" is deleted"))
-}
-
-// Rotate force refresh cached data
-func (c *Cache) Rotate(reset bool) {
-	c.rwmutex.Lock()
-	defer c.rwmutex.Unlock()
-
-	if reset {
-		c.old = &sync.Map{}
-	} else {
-		c.old = c.now
-	}
-	c.now = &sync.Map{}
-	c.barrier = &sync.Map{}
-}
diff --git a/util/suffix_tree.go b/pkg/suffixtree/suffix_tree.go
similarity index 99%
rename from util/suffix_tree.go
rename to pkg/suffixtree/suffix_tree.go
index 3b32ff2..797ad2e 100644
--- a/util/suffix_tree.go
+++ b/pkg/suffixtree/suffix_tree.go
@@ -1,4 +1,4 @@
-package util
+package suffixtree
 
 import (
 	"runtime"
diff --git a/util/suffix_tree_test.go b/pkg/suffixtree/suffix_tree_test.go
similarity index 72%
rename from util/suffix_tree_test.go
rename to pkg/suffixtree/suffix_tree_test.go
index fe52ba9..be3b413 100644
--- a/util/suffix_tree_test.go
+++ b/pkg/suffixtree/suffix_tree_test.go
@@ -1,9 +1,9 @@
-package util_test
+package suffixtree_test
 
 import (
 	"testing"
 
-	"github.com/wweir/sower/util"
+	"github.com/wweir/sower/pkg/suffixtree"
 )
 
 func TestNode_Match(t *testing.T) {
@@ -13,18 +13,18 @@ func TestNode_Match(t *testing.T) {
 	}
 	tests := []struct {
 		name  string
-		node  *util.Node
+		node  *suffixtree.Node
 		tests []test
 	}{{
 		"simple",
-		util.NewNodeFromRules("a.wweir.cc", "b.wweir.cc"),
+		suffixtree.NewNodeFromRules("a.wweir.cc", "b.wweir.cc"),
 		[]test{
 			{"a.wweir.cc", true},
 			{"b.wweir.cc", true},
 		},
 	}, {
 		"parent",
-		util.NewNodeFromRules("wweir.cc", "a.wweir.cc"),
+		suffixtree.NewNodeFromRules("wweir.cc", "a.wweir.cc"),
 		[]test{
 			{"wweir.cc", true},
 			{"a.wweir.cc", true},
@@ -32,7 +32,7 @@ func TestNode_Match(t *testing.T) {
 		},
 	}, {
 		"fuzz1",
-		util.NewNodeFromRules("wweir.cc", "a.wweir.cc", "*.wweir.cc"),
+		suffixtree.NewNodeFromRules("wweir.cc", "a.wweir.cc", "*.wweir.cc"),
 		[]test{
 			{"wweir.cc", true},
 			{"a.wweir.cc", true},
@@ -41,7 +41,7 @@ func TestNode_Match(t *testing.T) {
 		},
 	}, {
 		"fuzz2",
-		util.NewNodeFromRules("a.*.cc", "c.wweir.*"),
+		suffixtree.NewNodeFromRules("a.*.cc", "c.wweir.*"),
 		[]test{
 			{"wweir.cc", false},
 			{"a.wweir.cc", true},
@@ -50,7 +50,7 @@ func TestNode_Match(t *testing.T) {
 		},
 	}, {
 		"fuzz3",
-		util.NewNodeFromRules("*.*.cc", "iamp.*.*"),
+		suffixtree.NewNodeFromRules("*.*.cc", "iamp.*.*"),
 		[]test{
 			{"wweir.cc", false},
 			{"a.wweir.cc", true},
@@ -59,7 +59,7 @@ func TestNode_Match(t *testing.T) {
 		},
 	}, {
 		"fuzz4",
-		util.NewNodeFromRules("**.cc", "a.**.com", "**.wweir.*"),
+		suffixtree.NewNodeFromRules("**.cc", "a.**.com", "**.wweir.*"),
 		[]test{
 			{"wweir.cc", true},
 			{"a.wweir.cc", true},
diff --git a/pkg/teeconn/tee_conn.go b/pkg/teeconn/tee_conn.go
deleted file mode 100644
index c302949..0000000
--- a/pkg/teeconn/tee_conn.go
+++ /dev/null
@@ -1,56 +0,0 @@
-package teeconn
-
-import (
-	"io"
-	"net"
-)
-
-type Conn struct {
-	net.Conn
-
-	buf    []byte
-	offset int
-	stop   bool // read
-	err    error
-}
-
-func New(c net.Conn) *Conn {
-	return &Conn{Conn: c}
-}
-
-func (t *Conn) Reread() {
-	t.offset = 0
-}
-func (t *Conn) Reset() {
-	t.buf = []byte{}
-	t.offset = 0
-}
-func (t *Conn) Stop() *Conn {
-	t.stop = true
-	return t
-}
-
-func (t *Conn) Read(b []byte) (n int, err error) {
-	length := len(t.buf) - t.offset
-	if length > 0 {
-		n = copy(b, t.buf[t.offset:])
-		t.offset += n
-		return n, t.err
-	}
-
-	n, t.err = t.Conn.Read(b)
-	if !t.stop {
-		t.buf = append(t.buf, b[:n]...)
-		t.offset += n
-	}
-
-	return n, t.err
-}
-
-func (t *Conn) Write(b []byte) (n int, err error) {
-	if t.stop {
-		return t.Conn.Write(b)
-	}
-
-	return 0, io.ErrShortWrite
-}
diff --git a/router/country.go b/router/country.go
index ebec241..47feecc 100644
--- a/router/country.go
+++ b/router/country.go
@@ -5,7 +5,7 @@ import (
 	"net"
 	"time"
 
-	"github.com/wweir/deferlog/log"
+	"github.com/sower-proxy/deferlog/log"
 )
 
 func (r *Router) localSite(domain string) bool {
diff --git a/router/dns.go b/router/dns.go
index 7d703eb..2794209 100644
--- a/router/dns.go
+++ b/router/dns.go
@@ -5,7 +5,7 @@ import (
 	"time"
 
 	"github.com/miekg/dns"
-	"github.com/wweir/deferlog/log"
+	"github.com/sower-proxy/deferlog/log"
 )
 
 func (r *Router) ServeDNS(w dns.ResponseWriter, req *dns.Msg) {
diff --git a/router/ping.go b/router/ping.go
index 134f5d9..395571f 100644
--- a/router/ping.go
+++ b/router/ping.go
@@ -5,7 +5,7 @@ import (
 	"sync"
 	"time"
 
-	"github.com/wweir/deferlog/log"
+	"github.com/sower-proxy/deferlog/log"
 )
 
 var pingClient = http.Client{
diff --git a/router/router.go b/router/router.go
index 3f770ed..7f44b03 100644
--- a/router/router.go
+++ b/router/router.go
@@ -8,18 +8,19 @@ import (
 	"github.com/miekg/dns"
 	geoip2 "github.com/oschwald/geoip2-golang"
 	"github.com/pkg/errors"
-	"github.com/wweir/deferlog"
-	"github.com/wweir/deferlog/log"
+	"github.com/sower-proxy/conns/relay"
+	"github.com/sower-proxy/deferlog"
+	"github.com/sower-proxy/deferlog/log"
+	"github.com/sower-proxy/mem"
 	"github.com/wweir/sower/pkg/dhcp"
-	"github.com/wweir/sower/pkg/mem"
-	"github.com/wweir/sower/util"
+	"github.com/wweir/sower/pkg/suffixtree"
 )
 
 type ProxyDialFn func(network, host string, port uint16) (net.Conn, error)
 type Router struct {
-	blockRule   *util.Node
-	directRule  *util.Node
-	proxyRule   *util.Node
+	blockRule   *suffixtree.Node
+	directRule  *suffixtree.Node
+	proxyRule   *suffixtree.Node
 	ProxyDial   ProxyDialFn
 	accessCache *mem.Cache
 
@@ -57,13 +58,13 @@ func NewRouter(serveIP, fallbackDNS, mmdbFile string, proxyDial ProxyDialFn) *Ro
 }
 
 func (r *Router) SetBlockRules(blockList []string) {
-	r.blockRule = util.NewNodeFromRules(blockList...)
+	r.blockRule = suffixtree.NewNodeFromRules(blockList...)
 }
 func (r *Router) SetDirectRules(directList []string) {
-	r.directRule = util.NewNodeFromRules(directList...)
+	r.directRule = suffixtree.NewNodeFromRules(directList...)
 }
 func (r *Router) SetProxyRules(proxyList []string) {
-	r.proxyRule = util.NewNodeFromRules(proxyList...)
+	r.proxyRule = suffixtree.NewNodeFromRules(proxyList...)
 }
 func (r *Router) SetCountryCIDRs(directCIDRs []string) {
 	r.country.cidrs = make([]*net.IPNet, 0, len(directCIDRs))
@@ -139,11 +140,11 @@ func (r *Router) ProxyHandle(conn net.Conn, domain string, port uint16) error {
 	}
 	defer rc.Close()
 
-	util.Relay(conn, rc)
+	relay.Relay(conn, rc)
 	return nil
 }
 
 func (r *Router) DirectHandle(conn net.Conn, addr string) error {
-	dur, err := util.RelayTo(conn, addr)
+	dur, err := relay.RelayTo(conn, addr)
 	return errors.Wrapf(err, "spend (%s)", dur)
 }
diff --git a/transport/transport_test.go b/transport/transport_test.go
index d510ab5..be3d770 100644
--- a/transport/transport_test.go
+++ b/transport/transport_test.go
@@ -5,8 +5,8 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/wweir/deferlog/log"
-	"github.com/wweir/sower/pkg/teeconn"
+	"github.com/sower-proxy/conns/teeconn"
+	"github.com/sower-proxy/deferlog/log"
 	"github.com/wweir/sower/transport/sower"
 	"github.com/wweir/sower/transport/trojan"
 )
diff --git a/util/relay.go b/util/relay.go
deleted file mode 100644
index 3e3e5b9..0000000
--- a/util/relay.go
+++ /dev/null
@@ -1,50 +0,0 @@
-package util
-
-import (
-	"io"
-	"net"
-	"sync"
-	"sync/atomic"
-	"time"
-
-	"github.com/pkg/errors"
-)
-
-func RelayTo(conn net.Conn, addr string) (dur time.Duration, err error) {
-	if _, _, err := net.SplitHostPort(addr); err != nil {
-		addr = net.JoinHostPort(addr, "80")
-	}
-
-	start := time.Now()
-	rc, err := net.DialTimeout("tcp", addr, 5*time.Second)
-	if err != nil {
-		return time.Since(start), errors.WithStack(err)
-	}
-	defer rc.Close()
-
-	Relay(conn, rc)
-	return time.Since(start), nil
-}
-
-func Relay(conn1, conn2 net.Conn) {
-	wg := &sync.WaitGroup{}
-	exitFlag := new(int32)
-	wg.Add(2)
-	go redirect(conn2, conn1, wg, exitFlag)
-	redirect(conn1, conn2, wg, exitFlag)
-	wg.Wait()
-}
-func redirect(dst, src net.Conn, wg *sync.WaitGroup, exitFlag *int32) {
-
-	// io.Copy(dst, io.TeeReader(src, os.Stdout))
-	io.Copy(dst, src)
-
-	if atomic.CompareAndSwapInt32(exitFlag, 0, 1) {
-		// wakeup blocked goroutine
-		now := time.Now()
-		src.SetDeadline(now)
-		dst.SetDeadline(now)
-	}
-
-	wg.Done()
-}