diff --git a/api/resolver/subdomain/subdomain.go b/api/resolver/subdomain/subdomain.go
deleted file mode 100644
index c2c381a0..00000000
--- a/api/resolver/subdomain/subdomain.go
+++ /dev/null
@@ -1,85 +0,0 @@
-// Package subdomain is a resolver which uses the subdomain to determine the domain to route to. It
-// offloads the endpoint resolution to a child resolver which is provided in New.
-package subdomain
-
-import (
-	"net"
-	"net/http"
-	"strings"
-
-	"github.com/micro/go-micro/v3/api/resolver"
-	"github.com/micro/go-micro/v3/logger"
-	"golang.org/x/net/publicsuffix"
-)
-
-func NewResolver(parent resolver.Resolver, opts ...resolver.Option) resolver.Resolver {
-	options := resolver.NewOptions(opts...)
-	return &Resolver{options, parent}
-}
-
-type Resolver struct {
-	opts resolver.Options
-	resolver.Resolver
-}
-
-func (r *Resolver) Resolve(req *http.Request, opts ...resolver.ResolveOption) (*resolver.Endpoint, error) {
-	if dom := r.Domain(req); len(dom) > 0 {
-		opts = append(opts, resolver.Domain(dom))
-	}
-
-	return r.Resolver.Resolve(req, opts...)
-}
-
-func (r *Resolver) Domain(req *http.Request) string {
-	// determine the host, e.g. foobar.m3o.app
-	host := req.URL.Hostname()
-	if len(host) == 0 {
-		if h, _, err := net.SplitHostPort(req.Host); err == nil {
-			host = h // host does contain a port
-		} else if strings.Contains(err.Error(), "missing port in address") {
-			host = req.Host // host does not contain a port
-		}
-	}
-
-	// check for an ip address
-	if net.ParseIP(host) != nil {
-		return ""
-	}
-
-	// check for dev enviroment
-	if host == "localhost" || host == "127.0.0.1" {
-		return ""
-	}
-
-	// extract the top level domain plus one (e.g. 'myapp.com')
-	domain, err := publicsuffix.EffectiveTLDPlusOne(host)
-	if err != nil {
-		logger.Debugf("Unable to extract domain from %v", host)
-		return ""
-	}
-
-	// there was no subdomain
-	if host == domain {
-		return ""
-	}
-
-	// remove the domain from the host, leaving the subdomain, e.g. "staging.foo.myapp.com" => "staging.foo"
-	subdomain := strings.TrimSuffix(host, "."+domain)
-
-	// ignore the API subdomain
-	if subdomain == "api" {
-		return ""
-	}
-
-	// return the reversed subdomain as the namespace, e.g. "staging.foo" => "foo-staging"
-	comps := strings.Split(subdomain, ".")
-	for i := len(comps)/2 - 1; i >= 0; i-- {
-		opp := len(comps) - 1 - i
-		comps[i], comps[opp] = comps[opp], comps[i]
-	}
-	return strings.Join(comps, "-")
-}
-
-func (r *Resolver) String() string {
-	return "subdomain"
-}
diff --git a/api/resolver/subdomain/subdomain_test.go b/api/resolver/subdomain/subdomain_test.go
deleted file mode 100644
index 2a33fa60..00000000
--- a/api/resolver/subdomain/subdomain_test.go
+++ /dev/null
@@ -1,71 +0,0 @@
-package subdomain
-
-import (
-	"net/http"
-	"net/url"
-	"testing"
-
-	"github.com/micro/go-micro/v3/api/resolver/vpath"
-
-	"github.com/stretchr/testify/assert"
-)
-
-func TestResolve(t *testing.T) {
-	tt := []struct {
-		Name   string
-		Host   string
-		Result string
-	}{
-		{
-			Name:   "Top level domain",
-			Host:   "micro.mu",
-			Result: "micro",
-		},
-		{
-			Name:   "Effective top level domain",
-			Host:   "micro.com.au",
-			Result: "micro",
-		},
-		{
-			Name:   "Subdomain dev",
-			Host:   "dev.micro.mu",
-			Result: "dev",
-		},
-		{
-			Name:   "Subdomain foo",
-			Host:   "foo.micro.mu",
-			Result: "foo",
-		},
-		{
-			Name:   "Multi-level subdomain",
-			Host:   "staging.myapp.m3o.app",
-			Result: "myapp-staging",
-		},
-		{
-			Name:   "Dev host",
-			Host:   "127.0.0.1",
-			Result: "micro",
-		},
-		{
-			Name:   "Localhost",
-			Host:   "localhost",
-			Result: "micro",
-		},
-		{
-			Name:   "IP host",
-			Host:   "81.151.101.146",
-			Result: "micro",
-		},
-	}
-
-	for _, tc := range tt {
-		t.Run(tc.Name, func(t *testing.T) {
-			r := NewResolver(vpath.NewResolver())
-			result, err := r.Resolve(&http.Request{URL: &url.URL{Host: tc.Host, Path: "foo/bar"}})
-			assert.Nil(t, err, "Expecter err to be nil")
-			if result != nil {
-				assert.Equal(t, tc.Result, result.Domain, "Expected %v but got %v", tc.Result, result.Domain)
-			}
-		})
-	}
-}