diff --git a/cmd/transocks/main.go b/cmd/transocks/main.go
index 2b0cbc8..ad39070 100644
--- a/cmd/transocks/main.go
+++ b/cmd/transocks/main.go
@@ -7,15 +7,15 @@ import (
 	"net/url"
 
 	"github.com/BurntSushi/toml"
-	"github.com/cybozu-go/cmd"
 	"github.com/cybozu-go/log"
 	"github.com/cybozu-go/transocks"
+	"github.com/cybozu-go/well"
 )
 
 type tomlConfig struct {
-	Listen   string        `toml:"listen"`
-	ProxyURL string        `toml:"proxy_url"`
-	Log      cmd.LogConfig `toml:"log"`
+	Listen   string         `toml:"listen"`
+	ProxyURL string         `toml:"proxy_url"`
+	Log      well.LogConfig `toml:"log"`
 }
 
 const (
@@ -65,8 +65,8 @@ func serve(lns []net.Listener, c *transocks.Config) {
 	for _, ln := range lns {
 		s.Serve(ln)
 	}
-	err = cmd.Wait()
-	if err != nil && !cmd.IsSignaled(err) {
+	err = well.Wait()
+	if err != nil && !well.IsSignaled(err) {
 		log.ErrorExit(err)
 	}
 }
@@ -79,7 +79,7 @@ func main() {
 		log.ErrorExit(err)
 	}
 
-	g := &cmd.Graceful{
+	g := &well.Graceful{
 		Listen: func() ([]net.Listener, error) {
 			return transocks.Listeners(c)
 		},
@@ -89,8 +89,8 @@ func main() {
 	}
 	g.Run()
 
-	err = cmd.Wait()
-	if err != nil && !cmd.IsSignaled(err) {
+	err = well.Wait()
+	if err != nil && !well.IsSignaled(err) {
 		log.ErrorExit(err)
 	}
 }
diff --git a/config.go b/config.go
index 8ac1415..62e8aea 100644
--- a/config.go
+++ b/config.go
@@ -7,8 +7,8 @@ import (
 	"net/url"
 	"time"
 
-	"github.com/cybozu-go/cmd"
 	"github.com/cybozu-go/log"
+	"github.com/cybozu-go/well"
 )
 
 const (
@@ -58,9 +58,9 @@ type Config struct {
 	// If nil, the default logger is used.
 	Logger *log.Logger
 
-	// Env can be used to specify a cmd.Environment on which the server runs.
+	// Env can be used to specify a well.Environment on which the server runs.
 	// If nil, the server will run on the global environment.
-	Env *cmd.Environment
+	Env *well.Environment
 }
 
 // NewConfig creates and initializes a new Config.
diff --git a/server.go b/server.go
index ae7e1b4..35e534e 100644
--- a/server.go
+++ b/server.go
@@ -7,9 +7,9 @@ import (
 	"sync"
 	"time"
 
-	"github.com/cybozu-go/cmd"
 	"github.com/cybozu-go/log"
 	"github.com/cybozu-go/netutil"
+	"github.com/cybozu-go/well"
 	"golang.org/x/net/proxy"
 )
 
@@ -29,7 +29,7 @@ func Listeners(c *Config) ([]net.Listener, error) {
 
 // Server provides transparent proxy server functions.
 type Server struct {
-	cmd.Server
+	well.Server
 	mode   Mode
 	logger *log.Logger
 	dialer proxy.Dialer
@@ -60,7 +60,7 @@ func NewServer(c *Config) (*Server, error) {
 	}
 
 	s := &Server{
-		Server: cmd.Server{
+		Server: well.Server{
 			ShutdownTimeout: c.ShutdownTimeout,
 			Env:             c.Env,
 		},
@@ -86,7 +86,7 @@ func (s *Server) handleConnection(ctx context.Context, conn net.Conn) {
 		return
 	}
 
-	fields := cmd.FieldsFromContext(ctx)
+	fields := well.FieldsFromContext(ctx)
 	fields[log.FnType] = "access"
 	fields["client_addr"] = conn.RemoteAddr().String()
 
@@ -117,7 +117,7 @@ func (s *Server) handleConnection(ctx context.Context, conn net.Conn) {
 
 	// do proxy
 	st := time.Now()
-	env := cmd.NewEnvironment(ctx)
+	env := well.NewEnvironment(ctx)
 	env.Go(func(ctx context.Context) error {
 		buf := s.pool.Get().([]byte)
 		_, err := io.CopyBuffer(destConn, tc, buf)
@@ -141,7 +141,7 @@ func (s *Server) handleConnection(ctx context.Context, conn net.Conn) {
 	env.Stop()
 	err = env.Wait()
 
-	fields = cmd.FieldsFromContext(ctx)
+	fields = well.FieldsFromContext(ctx)
 	fields["elapsed"] = time.Since(st).Seconds()
 	if err != nil {
 		fields[log.FnError] = err.Error()