diff --git a/.travis.yml b/.travis.yml
index f724e8b..1a97bbf 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,6 +3,7 @@ language: go
 sudo: required
 
 go:
+  - "1.16"
   - tip
 
 service:
@@ -11,7 +12,6 @@ service:
 before_install:
   - echo $TRAVIS_GO_VERSION
   - go get github.com/mattn/goveralls
-  - go get go.etcd.io/etcd/clientv3
   - docker pull quay.io/coreos/etcd:v3.3.10
   - docker run -d -p 2379:2379 quay.io/coreos/etcd:v3.3.10 etcd --name casbin --listen-client-urls http://0.0.0.0:2379 --advertise-client-urls http://0.0.0.0:2379
 
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..da16758
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,20 @@
+module github.com/casbin/etcd-watcher
+
+go 1.16
+
+require (
+	github.com/casbin/casbin/v2 v2.30.2
+	github.com/cncf/udpa/go v0.0.0-20201120205902-5459f2c99403 // indirect
+	github.com/coreos/etcd v3.3.25+incompatible // indirect
+	github.com/coreos/go-semver v0.3.0 // indirect
+	github.com/coreos/go-systemd v0.0.0-20191104093116-d3cd4ed1dbcf // indirect
+	github.com/coreos/pkg v0.0.0-20180928190104-399ea9e2e55f // indirect
+	github.com/envoyproxy/go-control-plane v0.9.5 // indirect
+	github.com/gogo/protobuf v1.3.2 // indirect
+	github.com/golang/protobuf v1.5.2 // indirect
+	github.com/google/uuid v1.2.0 // indirect
+	github.com/stretchr/testify v1.5.1 // indirect
+	go.etcd.io/etcd v3.3.25+incompatible
+	go.uber.org/zap v1.16.0 // indirect
+	google.golang.org/grpc v1.26.0 // indirect; updating this breaks etcd
+)
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..235cfc5
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,195 @@
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diff --git a/watcher.go b/watcher.go
index 35deeb5..7caf292 100644
--- a/watcher.go
+++ b/watcher.go
@@ -21,7 +21,7 @@ import (
 	"strconv"
 	"time"
 
-	"github.com/casbin/casbin/persist"
+	"github.com/casbin/casbin/v2/persist"
 	"go.etcd.io/etcd/clientv3"
 	"go.etcd.io/etcd/etcdserver/api/v3rpc/rpctypes"
 )
@@ -57,7 +57,9 @@ func NewWatcher(endpoints []string, keyName string) (persist.Watcher, error) {
 	// Call the destructor when the object is released.
 	runtime.SetFinalizer(w, finalizer)
 
-	go w.startWatch()
+	go func() {
+		_ = w.startWatch()
+	}()
 
 	return w, nil
 }
diff --git a/watcher_test.go b/watcher_test.go
index 8c69423..bac56ff 100644
--- a/watcher_test.go
+++ b/watcher_test.go
@@ -18,7 +18,7 @@ import (
 	"log"
 	"testing"
 
-	"github.com/casbin/casbin"
+	"github.com/casbin/casbin/v2"
 )
 
 func updateCallback(rev string) {
@@ -33,7 +33,7 @@ func TestWatcher(t *testing.T) {
 	// listener represents any other Casbin enforcer instance that watches the change of policy in DB.
 	listener, _ := NewWatcher([]string{"http://127.0.0.1:2379"}, "/casbin")
 	// listener should set a callback that gets called when policy changes.
-	listener.SetUpdateCallback(updateCallback)
+	_ = listener.SetUpdateCallback(updateCallback)
 
 	// updater changes the policy, and sends the notifications.
 	err := updater.Update()
@@ -55,14 +55,17 @@ func TestWithEnforcer(t *testing.T) {
 	e, _ := casbin.NewEnforcer("examples/rbac_model.conf", "examples/rbac_policy.csv")
 
 	// Set the watcher for the enforcer.
-	e.SetWatcher(w)
+	_ = e.SetWatcher(w)
 
 	// By default, the watcher's callback is automatically set to the
 	// enforcer's LoadPolicy() in the SetWatcher() call.
 	// We can change it by explicitly setting a callback.
-	w.SetUpdateCallback(updateCallback)
+	_ = w.SetUpdateCallback(updateCallback)
 
 	// Update the policy to test the effect.
 	// You should see "[New revision detected: X]" in the log.
-	e.SavePolicy()
+	err := e.SavePolicy()
+	if err != nil {
+		t.Fail()
+	}
 }