diff --git a/codec.go b/codec.go
index 4851885..860e628 100644
--- a/codec.go
+++ b/codec.go
@@ -1,7 +1,7 @@
 package grpc
 
 import (
-	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v4/codec"
 	"google.golang.org/grpc/encoding"
 )
 
diff --git a/error.go b/error.go
index 170f169..c1a6cec 100644
--- a/error.go
+++ b/error.go
@@ -6,7 +6,7 @@ import (
 	"net/http"
 	"os"
 
-	"go.unistack.org/micro/v3/errors"
+	"go.unistack.org/micro/v4/errors"
 	"google.golang.org/grpc/codes"
 )
 
diff --git a/generate.go b/generate.go
index 5ea1f90..c351a9c 100644
--- a/generate.go
+++ b/generate.go
@@ -1,4 +1,4 @@
 package grpc
 
 //go:generate go install google.golang.org/grpc/cmd/protoc-gen-go-grpc@latest
-//go:generate sh -c "protoc -I./proto -I$(go list -f '{{ .Dir }}' -m go.unistack.org/micro-proto/v3) -I. --go-grpc_out=paths=source_relative:./proto --go_out=paths=source_relative:./proto proto/test.proto"
+//go:generate sh -c "protoc -I./proto -I$(go list -f '{{ .Dir }}' -m go.unistack.org/micro-proto/v4) -I. --go-grpc_out=paths=source_relative:./proto --go_out=paths=source_relative:./proto proto/test.proto"
diff --git a/go.mod b/go.mod
index defa97b..0c9683a 100644
--- a/go.mod
+++ b/go.mod
@@ -1,23 +1,22 @@
-module go.unistack.org/micro-server-grpc/v3
+module go.unistack.org/micro-server-grpc/v4
 
 go 1.22.0
 
-
 require (
-	go.unistack.org/micro/v3 v3.11.30
-	golang.org/x/net v0.33.0
-	google.golang.org/grpc v1.69.2
-	google.golang.org/protobuf v1.36.1
+	go.unistack.org/micro/v4 v4.1.2
+	golang.org/x/net v0.35.0
+	google.golang.org/grpc v1.70.0
+	google.golang.org/protobuf v1.36.5
 )
 
 require (
 	github.com/ash3in/uuidv8 v1.2.0 // indirect
 	github.com/google/uuid v1.6.0 // indirect
-	github.com/kr/pretty v0.3.1 // indirect
 	github.com/matoous/go-nanoid v1.5.1 // indirect
-	go.unistack.org/micro-proto/v3 v3.4.1 // indirect
-	golang.org/x/sys v0.28.0 // indirect
-	golang.org/x/text v0.21.0 // indirect
+	github.com/spf13/cast v1.7.1 // indirect
+	go.unistack.org/micro-proto/v4 v4.1.0 // indirect
+	golang.org/x/sys v0.30.0 // indirect
+	golang.org/x/text v0.22.0 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20241223144023-3abc09e42ca8 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )
diff --git a/go.sum b/go.sum
index 47e3cc3..141b7be 100644
--- a/go.sum
+++ b/go.sum
@@ -2,7 +2,8 @@ github.com/DATA-DOG/go-sqlmock v1.5.2 h1:OcvFkGmslmlZibjAjaHm3L//6LiuBgolP7Oputl
 github.com/DATA-DOG/go-sqlmock v1.5.2/go.mod h1:88MAG/4G7SMwSE3CeA0ZKzrT5CiOU3OJ+JlNzwDqpNU=
 github.com/ash3in/uuidv8 v1.2.0 h1:2oogGdtCPwaVtyvPPGin4TfZLtOGE5F+W++E880G6SI=
 github.com/ash3in/uuidv8 v1.2.0/go.mod h1:BnU0wJBxnzdEKmVg4xckBkD+VZuecTFTUP3M0dWgyY4=
-github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
+github.com/frankban/quicktest v1.14.6 h1:7Xjx+VpznH+oBnejlPUj8oUpdxnVs4f8XU8WnHkI4W8=
+github.com/frankban/quicktest v1.14.6/go.mod h1:4ptaffx2x8+WTWXmUCuVU6aPUX1/Mz7zb5vbUoiM6w0=
 github.com/go-logr/logr v1.4.2 h1:6pFjapn8bFcIbiKo3XT4j/BhANplGihG6tvd+8rYgrY=
 github.com/go-logr/logr v1.4.2/go.mod h1:9T104GzyrTigFIr8wt5mBrctHMim0Nb2HLGrmQ40KvY=
 github.com/go-logr/stdr v1.2.2 h1:hSWxHoqTgW2S2qGc0LTAI563KZ5YKYRhT3MFKZMbjag=
@@ -19,36 +20,36 @@ github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
 github.com/matoous/go-nanoid v1.5.1 h1:aCjdvTyO9LLnTIi0fgdXhOPPvOHjpXN6Ik9DaNjIct4=
 github.com/matoous/go-nanoid v1.5.1/go.mod h1:zyD2a71IubI24efhpvkJz+ZwfwagzgSO6UNiFsZKN7U=
-github.com/pkg/diff v0.0.0-20210226163009-20ebb0f2a09e/go.mod h1:pJLUxLENpZxwdsKMEsNbx1VGcRFpLqf3715MtcvvzbA=
-github.com/rogpeppe/go-internal v1.9.0/go.mod h1:WtVeX8xhTBvf0smdhujwtBcq4Qrzq/fJaraNFVN+nFs=
 github.com/rogpeppe/go-internal v1.13.1 h1:KvO1DLK/DRN07sQ1LQKScxyZJuNnedQ5/wKSR38lUII=
 github.com/rogpeppe/go-internal v1.13.1/go.mod h1:uMEvuHeurkdAXX61udpOXGD/AzZDWNMNyH2VO9fmH0o=
-go.opentelemetry.io/otel v1.31.0 h1:NsJcKPIW0D0H3NgzPDHmo0WW6SptzPdqg/L1zsIm2hY=
-go.opentelemetry.io/otel v1.31.0/go.mod h1:O0C14Yl9FgkjqcCZAsE053C13OaddMYr/hz6clDkEJE=
-go.opentelemetry.io/otel/metric v1.31.0 h1:FSErL0ATQAmYHUIzSezZibnyVlft1ybhy4ozRPcF2fE=
-go.opentelemetry.io/otel/metric v1.31.0/go.mod h1:C3dEloVbLuYoX41KpmAhOqNriGbA+qqH6PQ5E5mUfnY=
-go.opentelemetry.io/otel/sdk v1.31.0 h1:xLY3abVHYZ5HSfOg3l2E5LUj2Cwva5Y7yGxnSW9H5Gk=
-go.opentelemetry.io/otel/sdk v1.31.0/go.mod h1:TfRbMdhvxIIr/B2N2LQW2S5v9m3gOQ/08KsbbO5BPT0=
-go.opentelemetry.io/otel/sdk/metric v1.31.0 h1:i9hxxLJF/9kkvfHppyLL55aW7iIJz4JjxTeYusH7zMc=
-go.opentelemetry.io/otel/sdk/metric v1.31.0/go.mod h1:CRInTMVvNhUKgSAMbKyTMxqOBC0zgyxzW55lZzX43Y8=
-go.opentelemetry.io/otel/trace v1.31.0 h1:ffjsj1aRouKewfr85U2aGagJ46+MvodynlQ1HYdmJys=
-go.opentelemetry.io/otel/trace v1.31.0/go.mod h1:TXZkRk7SM2ZQLtR6eoAWQFIHPvzQ06FJAsO1tJg480A=
-go.unistack.org/micro-proto/v3 v3.4.1 h1:UTjLSRz2YZuaHk9iSlVqqsA50JQNAEK2ZFboGqtEa9Q=
-go.unistack.org/micro-proto/v3 v3.4.1/go.mod h1:okx/cnOhzuCX0ggl/vToatbCupi0O44diiiLLsZ93Zo=
-go.unistack.org/micro/v3 v3.11.30 h1:XTLgZubSGzQL85IUMp1pTJnS1lP4eFwTZyelV/SzOMc=
-go.unistack.org/micro/v3 v3.11.30/go.mod h1:fvOkXKs3wKHToWH6Mxy+aovEiDl2q4UlOCdVfJdziBU=
-golang.org/x/net v0.33.0 h1:74SYHlV8BIgHIFC/LrYkOGIwL19eTYXQ5wc6TBuO36I=
-golang.org/x/net v0.33.0/go.mod h1:HXLR5J+9DxmrqMwG9qjGCxZ+zKXxBru04zlTvWlWuN4=
-golang.org/x/sys v0.28.0 h1:Fksou7UEQUWlKvIdsqzJmUmCX3cZuD2+P3XyyzwMhlA=
-golang.org/x/sys v0.28.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
-golang.org/x/text v0.21.0 h1:zyQAAkrwaneQ066sspRyJaG9VNi/YJ1NfzcGB3hZ/qo=
-golang.org/x/text v0.21.0/go.mod h1:4IBbMaMmOPCJ8SecivzSH54+73PCFmPWxNTLm+vZkEQ=
+github.com/spf13/cast v1.7.1 h1:cuNEagBQEHWN1FnbGEjCXL2szYEXqfJPbP2HNUaca9Y=
+github.com/spf13/cast v1.7.1/go.mod h1:ancEpBxwJDODSW/UG4rDrAqiKolqNNh2DX3mk86cAdo=
+go.opentelemetry.io/otel v1.32.0 h1:WnBN+Xjcteh0zdk01SVqV55d/m62NJLJdIyb4y/WO5U=
+go.opentelemetry.io/otel v1.32.0/go.mod h1:00DCVSB0RQcnzlwyTfqtxSm+DRr9hpYrHjNGiBHVQIg=
+go.opentelemetry.io/otel/metric v1.32.0 h1:xV2umtmNcThh2/a/aCP+h64Xx5wsj8qqnkYZktzNa0M=
+go.opentelemetry.io/otel/metric v1.32.0/go.mod h1:jH7CIbbK6SH2V2wE16W05BHCtIDzauciCRLoc/SyMv8=
+go.opentelemetry.io/otel/sdk v1.32.0 h1:RNxepc9vK59A8XsgZQouW8ue8Gkb4jpWtJm9ge5lEG4=
+go.opentelemetry.io/otel/sdk v1.32.0/go.mod h1:LqgegDBjKMmb2GC6/PrTnteJG39I8/vJCAP9LlJXEjU=
+go.opentelemetry.io/otel/sdk/metric v1.32.0 h1:rZvFnvmvawYb0alrYkjraqJq0Z4ZUJAiyYCU9snn1CU=
+go.opentelemetry.io/otel/sdk/metric v1.32.0/go.mod h1:PWeZlq0zt9YkYAp3gjKZ0eicRYvOh1Gd+X99x6GHpCQ=
+go.opentelemetry.io/otel/trace v1.32.0 h1:WIC9mYrXf8TmY/EXuULKc8hR17vE+Hjv2cssQDe03fM=
+go.opentelemetry.io/otel/trace v1.32.0/go.mod h1:+i4rkvCraA+tG6AzwloGaCtkx53Fa+L+V8e9a7YvhT8=
+go.unistack.org/micro-proto/v4 v4.1.0 h1:qPwL2n/oqh9RE3RTTDgt28XK3QzV597VugQPaw9lKUk=
+go.unistack.org/micro-proto/v4 v4.1.0/go.mod h1:ArmK7o+uFvxSY3dbJhKBBX4Pm1rhWdLEFf3LxBrMtec=
+go.unistack.org/micro/v4 v4.1.2 h1:9SOlPYyPNNFpg1A7BsvhDyQm3gysLH1AhWbDCp1hyoY=
+go.unistack.org/micro/v4 v4.1.2/go.mod h1:lr3oYED8Ay1vjK68QqRw30QOtdk/ffpZqMFDasOUhKw=
+golang.org/x/net v0.35.0 h1:T5GQRQb2y08kTAByq9L4/bz8cipCdA8FbRTXewonqY8=
+golang.org/x/net v0.35.0/go.mod h1:EglIi67kWsHKlRzzVMUD93VMSWGFOMSZgxFjparz1Qk=
+golang.org/x/sys v0.30.0 h1:QjkSwP/36a20jFYWkSue1YwXzLmsV5Gfq7Eiy72C1uc=
+golang.org/x/sys v0.30.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/text v0.22.0 h1:bofq7m3/HAFvbF51jz3Q9wLg3jkvSPuiZu/pD1XwgtM=
+golang.org/x/text v0.22.0/go.mod h1:YRoo4H8PVmsu+E3Ou7cqLVH8oXWIHVoX0jqUWALQhfY=
 google.golang.org/genproto/googleapis/rpc v0.0.0-20241223144023-3abc09e42ca8 h1:TqExAhdPaB60Ux47Cn0oLV07rGnxZzIsaRhQaqS666A=
 google.golang.org/genproto/googleapis/rpc v0.0.0-20241223144023-3abc09e42ca8/go.mod h1:lcTa1sDdWEIHMWlITnIczmw5w60CF9ffkb8Z+DVmmjA=
-google.golang.org/grpc v1.69.2 h1:U3S9QEtbXC0bYNvRtcoklF3xGtLViumSYxWykJS+7AU=
-google.golang.org/grpc v1.69.2/go.mod h1:vyjdE6jLBI76dgpDojsFGNaHlxdjXN9ghpnd2o7JGZ4=
-google.golang.org/protobuf v1.36.1 h1:yBPeRvTftaleIgM3PZ/WBIZ7XM/eEYAaEyCwvyjq/gk=
-google.golang.org/protobuf v1.36.1/go.mod h1:9fA7Ob0pmnwhb644+1+CVWFRbNajQ6iRojtC/QF5bRE=
+google.golang.org/grpc v1.70.0 h1:pWFv03aZoHzlRKHWicjsZytKAiYCtNS0dHbXnIdq7jQ=
+google.golang.org/grpc v1.70.0/go.mod h1:ofIJqVKDXx/JiXrwr2IG4/zwdH9txy3IlF40RmcJSQw=
+google.golang.org/protobuf v1.36.5 h1:tPhr+woSbjfYvY6/GPufUoYizxw1cF/yFoxJ2fmpwlM=
+google.golang.org/protobuf v1.36.5/go.mod h1:9fA7Ob0pmnwhb644+1+CVWFRbNajQ6iRojtC/QF5bRE=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c/go.mod h1:JHkPIbrfpd72SG/EVd6muEfDQjcINNoR0C8j2r3qZ4Q=
diff --git a/grpc.go b/grpc.go
index 3af6dee..4549c7a 100644
--- a/grpc.go
+++ b/grpc.go
@@ -10,7 +10,6 @@ import (
 	"slices"
 	"sort"
 	"strconv"
-	"strings"
 	"sync"
 	"sync/atomic"
 	"time"
@@ -19,18 +18,16 @@ import (
 	reflectionv1pb "google.golang.org/grpc/reflection/grpc_reflection_v1"
 
 	// nolint: staticcheck
-	"go.unistack.org/micro/v3/broker"
-	"go.unistack.org/micro/v3/codec"
-	"go.unistack.org/micro/v3/errors"
-	"go.unistack.org/micro/v3/logger"
-	"go.unistack.org/micro/v3/metadata"
-	"go.unistack.org/micro/v3/meter"
-	"go.unistack.org/micro/v3/options"
-	"go.unistack.org/micro/v3/register"
-	"go.unistack.org/micro/v3/semconv"
-	"go.unistack.org/micro/v3/server"
-	msync "go.unistack.org/micro/v3/sync"
-	"go.unistack.org/micro/v3/tracer"
+
+	"go.unistack.org/micro/v4/errors"
+	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/meter"
+	"go.unistack.org/micro/v4/options"
+	"go.unistack.org/micro/v4/register"
+	"go.unistack.org/micro/v4/semconv"
+	"go.unistack.org/micro/v4/server"
+	"go.unistack.org/micro/v4/tracer"
 	"golang.org/x/net/netutil"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/codes"
@@ -46,13 +43,6 @@ const (
 	DefaultContentType = "application/grpc"
 )
 
-/*
-type ServerReflection struct {
-	srv *grpc.Server
-	s   *serverReflectionServer
-}
-*/
-
 type streamWrapper struct {
 	ctx context.Context
 	grpc.ServerStream
@@ -69,9 +59,7 @@ type Server struct {
 	handlers       map[string]server.Handler
 	srv            *grpc.Server
 	exit           chan chan error
-	wg             *msync.WaitGroup
 	rsvc           *register.Service
-	subscribers    map[*subscriber][]broker.Subscriber
 	rpc            *rServer
 	opts           server.Options
 	unknownHandler grpc.StreamHandler
@@ -92,7 +80,6 @@ func newServer(opts ...server.Option) *Server {
 			serviceMap: make(map[string]*service),
 		},
 		handlers:    make(map[string]server.Handler),
-		subscribers: make(map[*subscriber][]broker.Subscriber),
 		exit:        make(chan chan error),
 		stateLive:   &atomic.Uint32{},
 		stateReady:  &atomic.Uint32{},
@@ -104,22 +91,6 @@ func newServer(opts ...server.Option) *Server {
 	return g
 }
 
-/*
-type grpcRouter struct {
- h func(context.Context, server.Request, interface{}) error
- m func(context.Context, server.Message) error
-}
-
-func (r grpcRouter) ProcessMessage(ctx context.Context, msg server.Message) error {
- return r.m(ctx, msg)
-}
-
-func (r grpcRouter) ServeRequest(ctx context.Context, req server.Request, rsp server.Response) error {
- return r.h(ctx, req, rsp)
-}
-
-*/
-
 func (g *Server) configure(opts ...server.Option) error {
 	g.Lock()
 	defer g.Unlock()
@@ -215,8 +186,9 @@ func (g *Server) handler(srv interface{}, stream grpc.ServerStream) error {
 		return status.Errorf(codes.Internal, "method does not exist in context")
 	}
 
+	var gmd map[string][]string
 	// get grpc metadata
-	gmd, ok := gmetadata.FromIncomingContext(ctx)
+	gmd, ok = gmetadata.FromIncomingContext(ctx)
 	if !ok {
 		gmd = gmetadata.MD{}
 	}
@@ -249,25 +221,23 @@ func (g *Server) handler(srv interface{}, stream grpc.ServerStream) error {
 		}()
 	}
 
-	md := metadata.New(len(gmd))
-	for k, v := range gmd {
-		md[k] = strings.Join(v, ", ")
-	}
-	md.Set("Path", fullMethod)
-	md.Set("Micro-Server", "grpc")
+	md := metadata.Copy(gmd)
+
+	md.Set("path", fullMethod)
+	md.Set("micro-server", "grpc")
 	md.Set(metadata.HeaderEndpoint, methodName)
 	md.Set(metadata.HeaderService, serviceName)
 
 	var td string
 	// timeout for server deadline
-	if v, ok := md.Get("timeout"); ok {
+	if v, ok := md.Get("timeout"); ok && len(v) > 0 {
 		md.Del("timeout")
-		td = v
+		td = v[0]
 	}
-	if v, ok := md.Get("Grpc-Timeout"); ok {
-		md.Del("Grpc-Timeout")
-		td = v[:len(v)-1]
-		switch v[len(v)-1:] {
+	if v, ok := md.Get("grpc-timeout"); ok && len(v) > 0 {
+		md.Del("grpc-timeout")
+		td = v[0][:len(v)-1]
+		switch v[0][len(v)-1:] {
 		case "S":
 			td += "s"
 		case "M":
@@ -286,11 +256,8 @@ func (g *Server) handler(srv interface{}, stream grpc.ServerStream) error {
 	// get content type
 	ct := DefaultContentType
 
-	if ctype, ok := md.Get("content-type"); ok {
-		ct = ctype
-	} else if ctype, ok := md.Get("x-content-type"); ok {
-		ct = ctype
-		md.Del("x-content-type")
+	if ctype, ok := md.Get("content-type"); ok && len(ctype) > 0 {
+		ct = ctype[0]
 	}
 
 	// create new context
@@ -323,7 +290,7 @@ func (g *Server) handler(srv interface{}, stream grpc.ServerStream) error {
 
 	// get peer from context
 	if p, ok := peer.FromContext(ctx); ok {
-		md.Set("Remote", p.Addr.String())
+		md.Set("remote", p.Addr.String())
 		ctx = peer.NewContext(ctx, p)
 	}
 
@@ -431,7 +398,7 @@ func (g *Server) processRequest(ctx context.Context, stream grpc.ServerStream, s
 	// execute the handler
 	appErr := fn(ctx, r, replyv.Interface())
 	if outmd, ok := metadata.FromOutgoingContext(ctx); ok {
-		if err = stream.SendHeader(gmetadata.New(outmd)); err != nil {
+		if err = stream.SendHeader(gmetadata.MD(outmd.Copy())); err != nil {
 			return err
 		}
 	}
@@ -515,7 +482,7 @@ func (g *Server) processStream(ctx context.Context, stream grpc.ServerStream, se
 
 	appErr := fn(ctx, r, ss)
 	if outmd, ok := metadata.FromOutgoingContext(ctx); ok {
-		if err := stream.SendHeader(gmetadata.New(outmd)); err != nil {
+		if err := stream.SendHeader(gmetadata.MD(outmd.Copy())); err != nil {
 			return err
 		}
 	}
@@ -551,21 +518,6 @@ func (g *Server) processStream(ctx context.Context, stream grpc.ServerStream, se
 	return status.New(statusCode, statusDesc).Err()
 }
 
-func (g *Server) newCodec(ct string) (codec.Codec, error) {
-	g.RLock()
-	defer g.RUnlock()
-
-	if idx := strings.IndexRune(ct, ';'); idx >= 0 {
-		ct = ct[:idx]
-	}
-
-	if c, ok := g.opts.Codecs[ct]; ok {
-		return c, nil
-	}
-
-	return nil, codec.ErrUnknownContentType
-}
-
 func (g *Server) Options() server.Options {
 	g.RLock()
 	opts := g.opts
@@ -591,34 +543,6 @@ func (g *Server) Handle(h server.Handler) error {
 	return nil
 }
 
-func (g *Server) NewSubscriber(topic string, sb interface{}, opts ...server.SubscriberOption) server.Subscriber {
-	return newSubscriber(topic, sb, opts...)
-}
-
-func (g *Server) Subscribe(sb server.Subscriber) error {
-	sub, ok := sb.(*subscriber)
-	if !ok {
-		return fmt.Errorf("invalid subscriber: expected *subscriber")
-	}
-	if len(sub.handlers) == 0 {
-		return fmt.Errorf("invalid subscriber: no handler functions")
-	}
-
-	if err := server.ValidateSubscriber(sb); err != nil {
-		return err
-	}
-
-	g.Lock()
-	if _, ok = g.subscribers[sub]; ok {
-		g.Unlock()
-		return fmt.Errorf("subscriber %v already exists", sub)
-	}
-
-	g.subscribers[sub] = nil
-	g.Unlock()
-	return nil
-}
-
 func (g *Server) Register() error {
 	g.RLock()
 	rsvc := g.rsvc
@@ -648,15 +572,6 @@ func (g *Server) Register() error {
 
 	sort.Strings(handlerList)
 
-	subscriberList := make([]*subscriber, 0, len(g.subscribers))
-	for e := range g.subscribers {
-		// Only advertise non internal subscribers
-		subscriberList = append(subscriberList, e)
-	}
-	sort.Slice(subscriberList, func(i, j int) bool {
-		return subscriberList[i].topic > subscriberList[j].topic
-	})
-
 	g.RUnlock()
 
 	g.RLock()
@@ -718,26 +633,6 @@ func (g *Server) Deregister() error {
 
 	g.registered = false
 
-	wg := sync.WaitGroup{}
-	for sb, subs := range g.subscribers {
-		for _, sub := range subs {
-			wg.Add(1)
-			go func(s broker.Subscriber) {
-				defer wg.Done()
-				if config.Logger.V(logger.InfoLevel) {
-					config.Logger.Info(config.Context, "Unsubscribing from topic: "+s.Topic())
-				}
-				if err := s.Unsubscribe(g.opts.Context); err != nil {
-					if config.Logger.V(logger.ErrorLevel) {
-						config.Logger.Error(config.Context, "Unsubscribing from topic: "+s.Topic(), err)
-					}
-				}
-			}(sub)
-		}
-		g.subscribers[sb] = nil
-	}
-	wg.Wait()
-
 	g.Unlock()
 	return nil
 }
@@ -785,21 +680,6 @@ func (g *Server) Start() error {
 	}
 	g.Unlock()
 
-	// only connect if we're subscribed
-	if len(g.subscribers) > 0 {
-		// connect to the broker
-		if err = config.Broker.Connect(config.Context); err != nil {
-			if config.Logger.V(logger.ErrorLevel) {
-				config.Logger.Error(config.Context, fmt.Sprintf("broker [%s] connect error", config.Broker.String()), err)
-			}
-			return err
-		}
-
-		if config.Logger.V(logger.InfoLevel) {
-			config.Logger.Info(config.Context, fmt.Sprintf("broker [%s] Connected to %s", config.Broker.String(), config.Broker.Address()))
-		}
-	}
-
 	// use RegisterCheck func before register
 	// nolint: nestif
 	if err = g.opts.RegisterCheck(config.Context); err != nil {
@@ -815,10 +695,6 @@ func (g *Server) Start() error {
 		}
 	}
 
-	if err = g.subscribe(); err != nil {
-		return err
-	}
-
 	// micro: go ts.Accept(s.accept)
 	go func() {
 		if err = g.srv.Serve(ts); err != nil {
diff --git a/handler.go b/handler.go
index af7af8f..2b5017a 100644
--- a/handler.go
+++ b/handler.go
@@ -3,7 +3,7 @@ package grpc
 import (
 	"reflect"
 
-	"go.unistack.org/micro/v3/server"
+	"go.unistack.org/micro/v4/server"
 )
 
 type rpcHandler struct {
diff --git a/options.go b/options.go
index be712aa..f730f0c 100644
--- a/options.go
+++ b/options.go
@@ -3,7 +3,7 @@ package grpc
 import (
 	"context"
 
-	"go.unistack.org/micro/v3/server"
+	"go.unistack.org/micro/v4/server"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/encoding"
 )
diff --git a/reflection_test.go b/reflection_test.go
index 4a2780f..48320b4 100644
--- a/reflection_test.go
+++ b/reflection_test.go
@@ -3,9 +3,8 @@ package grpc
 import (
 	"fmt"
 	"testing"
-
-	_ "go.unistack.org/micro-server-grpc/v3/proto"
-	"go.unistack.org/micro/v3/server"
+	
+	"go.unistack.org/micro/v4/server"
 	"google.golang.org/grpc"
 	"google.golang.org/protobuf/reflect/protoreflect"
 	"google.golang.org/protobuf/reflect/protoregistry"
diff --git a/request.go b/request.go
index 86260be..ed9f520 100644
--- a/request.go
+++ b/request.go
@@ -1,9 +1,9 @@
 package grpc
 
 import (
-	"go.unistack.org/micro/v3/codec"
-	"go.unistack.org/micro/v3/metadata"
-	"go.unistack.org/micro/v3/server"
+	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/server"
 )
 
 var _ server.Request = &rpcRequest{}
diff --git a/response.go b/response.go
index b1ad9b7..a317d28 100644
--- a/response.go
+++ b/response.go
@@ -1,9 +1,9 @@
 package grpc
 
 import (
-	"go.unistack.org/micro/v3/codec"
-	"go.unistack.org/micro/v3/metadata"
-	"go.unistack.org/micro/v3/server"
+	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/server"
 )
 
 var _ server.Response = &rpcResponse{}
diff --git a/server.go b/server.go
index c1e064c..73f0851 100644
--- a/server.go
+++ b/server.go
@@ -14,7 +14,7 @@ import (
 	"unicode"
 	"unicode/utf8"
 
-	"go.unistack.org/micro/v3/server"
+	"go.unistack.org/micro/v4/server"
 )
 
 // Precompute the reflect type for error. Can't use error directly
@@ -47,8 +47,8 @@ type rServer struct {
 
 // Is this an exported - upper case - name?
 func isExported(name string) bool {
-	rune, _ := utf8.DecodeRuneInString(name)
-	return unicode.IsUpper(rune)
+	r, _ := utf8.DecodeRuneInString(name)
+	return unicode.IsUpper(r)
 }
 
 // Is this type exported or a builtin?
@@ -123,43 +123,43 @@ func prepareEndpoint(method reflect.Method) (*methodType, error) {
 	return &methodType{method: method, ArgType: argType, ReplyType: replyType, ContextType: contextType, stream: stream}, nil
 }
 
-func (server *rServer) register(rcvr interface{}) error {
-	server.mu.Lock()
-	defer server.mu.Unlock()
-	if server.serviceMap == nil {
-		server.serviceMap = make(map[string]*service)
+func (s *rServer) register(rcvr interface{}) error {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if s.serviceMap == nil {
+		s.serviceMap = make(map[string]*service)
 	}
-	s := &service{}
-	s.typ = reflect.TypeOf(rcvr)
-	s.rcvr = reflect.ValueOf(rcvr)
-	sname := reflect.Indirect(s.rcvr).Type().Name()
+	srv := &service{}
+	srv.typ = reflect.TypeOf(rcvr)
+	srv.rcvr = reflect.ValueOf(rcvr)
+	sname := reflect.Indirect(srv.rcvr).Type().Name()
 	if sname == "" {
-		return fmt.Errorf("rpc: no service name for type %v", s.typ.String())
+		return fmt.Errorf("rpc: no service name for type %v", srv.typ.String())
 	}
 	if !isExported(sname) {
 		return fmt.Errorf("rpc Register: type %s is not exported", sname)
 	}
-	if _, present := server.serviceMap[sname]; present {
+	if _, present := s.serviceMap[sname]; present {
 		return fmt.Errorf("rpc: service already defined: %s", sname)
 	}
-	s.name = sname
-	s.method = make(map[string]*methodType)
+	srv.name = sname
+	srv.method = make(map[string]*methodType)
 
 	// Install the methods
-	for m := 0; m < s.typ.NumMethod(); m++ {
-		method := s.typ.Method(m)
+	for m := 0; m < srv.typ.NumMethod(); m++ {
+		method := srv.typ.Method(m)
 		mt, err := prepareEndpoint(method)
 		if mt != nil && err == nil {
-			s.method[method.Name] = mt
+			srv.method[method.Name] = mt
 		} else if err != nil {
 			return err
 		}
 	}
 
-	if len(s.method) == 0 {
+	if len(srv.method) == 0 {
 		return fmt.Errorf("rpc Register: type %s has no exported methods of suitable type", sname)
 	}
-	server.serviceMap[s.name] = s
+	s.serviceMap[srv.name] = srv
 	return nil
 }
 
diff --git a/stream.go b/stream.go
index 96447e5..cad4d55 100644
--- a/stream.go
+++ b/stream.go
@@ -3,7 +3,7 @@ package grpc
 import (
 	"context"
 
-	"go.unistack.org/micro/v3/server"
+	"go.unistack.org/micro/v4/server"
 	"google.golang.org/grpc"
 )
 
diff --git a/subscriber.go b/subscriber.go
deleted file mode 100644
index e3ef6b3..0000000
--- a/subscriber.go
+++ /dev/null
@@ -1,258 +0,0 @@
-package grpc
-
-import (
-	"context"
-	"fmt"
-	"reflect"
-	"strings"
-
-	"go.unistack.org/micro/v3/broker"
-	"go.unistack.org/micro/v3/codec"
-	"go.unistack.org/micro/v3/logger"
-	"go.unistack.org/micro/v3/metadata"
-	"go.unistack.org/micro/v3/options"
-	"go.unistack.org/micro/v3/server"
-)
-
-var _ server.Message = &rpcMessage{}
-
-type rpcMessage struct {
-	payload     interface{}
-	codec       codec.Codec
-	header      metadata.Metadata
-	topic       string
-	contentType string
-}
-
-func (r *rpcMessage) ContentType() string {
-	return r.contentType
-}
-
-func (r *rpcMessage) Topic() string {
-	return r.topic
-}
-
-func (r *rpcMessage) Body() interface{} {
-	return r.payload
-}
-
-func (r *rpcMessage) Header() metadata.Metadata {
-	return r.header
-}
-
-func (r *rpcMessage) Codec() codec.Codec {
-	return r.codec
-}
-
-type handler struct {
-	reqType reflect.Type
-	ctxType reflect.Type
-	method  reflect.Value
-}
-
-type subscriber struct {
-	topic      string
-	rcvr       reflect.Value
-	typ        reflect.Type
-	subscriber interface{}
-	handlers   []*handler
-	opts       server.SubscriberOptions
-}
-
-func newSubscriber(topic string, sub interface{}, opts ...server.SubscriberOption) server.Subscriber {
-	options := server.NewSubscriberOptions(opts...)
-
-	var handlers []*handler
-
-	if typ := reflect.TypeOf(sub); typ.Kind() == reflect.Func {
-		h := &handler{
-			method: reflect.ValueOf(sub),
-		}
-
-		switch typ.NumIn() {
-		case 1:
-			h.reqType = typ.In(0)
-		case 2:
-			h.ctxType = typ.In(0)
-			h.reqType = typ.In(1)
-		}
-
-		handlers = append(handlers, h)
-
-	} else {
-		for m := 0; m < typ.NumMethod(); m++ {
-			method := typ.Method(m)
-			h := &handler{
-				method: method.Func,
-			}
-
-			switch method.Type.NumIn() {
-			case 2:
-				h.reqType = method.Type.In(1)
-			case 3:
-				h.ctxType = method.Type.In(1)
-				h.reqType = method.Type.In(2)
-			}
-
-			handlers = append(handlers, h)
-
-		}
-	}
-
-	return &subscriber{
-		rcvr:       reflect.ValueOf(sub),
-		typ:        reflect.TypeOf(sub),
-		topic:      topic,
-		subscriber: sub,
-		handlers:   handlers,
-		opts:       options,
-	}
-}
-
-func (g *Server) createSubHandler(sb *subscriber, opts server.Options) broker.Handler {
-	return func(p broker.Event) (err error) {
-		msg := p.Message()
-		// if we don't have headers, create empty map
-		if msg.Header == nil {
-			msg.Header = make(map[string]string)
-		}
-
-		ct := msg.Header["Content-Type"]
-		if len(ct) == 0 {
-			msg.Header["Content-Type"] = DefaultContentType
-			ct = DefaultContentType
-		}
-		cf, err := g.newCodec(ct)
-		if err != nil {
-			return err
-		}
-
-		hdr := make(map[string]string, len(msg.Header))
-		for k, v := range msg.Header {
-			hdr[k] = v
-		}
-
-		ctx := metadata.NewIncomingContext(sb.opts.Context, hdr)
-
-		results := make(chan error, len(sb.handlers))
-
-		for i := 0; i < len(sb.handlers); i++ {
-			handler := sb.handlers[i]
-
-			var isVal bool
-			var req reflect.Value
-
-			if handler.reqType.Kind() == reflect.Ptr {
-				req = reflect.New(handler.reqType.Elem())
-			} else {
-				req = reflect.New(handler.reqType)
-				isVal = true
-			}
-			if isVal {
-				req = req.Elem()
-			}
-
-			if err = cf.Unmarshal(msg.Body, req.Interface()); err != nil {
-				return err
-			}
-
-			fn := func(ctx context.Context, msg server.Message) error {
-				var vals []reflect.Value
-				if sb.typ.Kind() != reflect.Func {
-					vals = append(vals, sb.rcvr)
-				}
-				if handler.ctxType != nil {
-					vals = append(vals, reflect.ValueOf(ctx))
-				}
-
-				vals = append(vals, reflect.ValueOf(msg.Body()))
-
-				returnValues := handler.method.Call(vals)
-				if rerr := returnValues[0].Interface(); rerr != nil {
-					return rerr.(error)
-				}
-				return nil
-			}
-
-			opts.Hooks.EachPrev(func(hook options.Hook) {
-				if h, ok := hook.(server.HookSubHandler); ok {
-					fn = h(fn)
-				}
-			})
-
-			if g.wg != nil {
-				g.wg.Add(1)
-			}
-			go func() {
-				if g.wg != nil {
-					defer g.wg.Done()
-				}
-				cerr := fn(ctx, &rpcMessage{
-					topic:       sb.topic,
-					contentType: ct,
-					payload:     req.Interface(),
-					header:      msg.Header,
-				})
-				results <- cerr
-			}()
-		}
-		var errors []string
-		for i := 0; i < len(sb.handlers); i++ {
-			if rerr := <-results; rerr != nil {
-				errors = append(errors, rerr.Error())
-			}
-		}
-		if len(errors) > 0 {
-			err = fmt.Errorf("subscriber error: %s", strings.Join(errors, "\n"))
-		}
-
-		return err
-	}
-}
-
-func (s *subscriber) Topic() string {
-	return s.topic
-}
-
-func (s *subscriber) Subscriber() interface{} {
-	return s.subscriber
-}
-
-func (s *subscriber) Options() server.SubscriberOptions {
-	return s.opts
-}
-
-func (g *Server) subscribe() error {
-	config := g.opts
-	subCtx := config.Context
-
-	for sb := range g.subscribers {
-
-		if cx := sb.Options().Context; cx != nil {
-			subCtx = cx
-		}
-
-		opts := []broker.SubscribeOption{
-			broker.SubscribeContext(subCtx),
-			broker.SubscribeAutoAck(sb.Options().AutoAck),
-			broker.SubscribeBodyOnly(sb.Options().BodyOnly),
-		}
-
-		if queue := sb.Options().Queue; len(queue) > 0 {
-			opts = append(opts, broker.SubscribeGroup(queue))
-		}
-
-		if config.Logger.V(logger.InfoLevel) {
-			config.Logger.Info(config.Context, "subscribing to topic: "+sb.Topic())
-		}
-
-		sub, err := config.Broker.Subscribe(subCtx, sb.Topic(), g.createSubHandler(sb, config), opts...)
-		if err != nil {
-			return err
-		}
-
-		g.subscribers[sb] = []broker.Subscriber{sub}
-	}
-
-	return nil
-}