diff --git a/examples/addsvc/client/grpc/factory.go b/examples/addsvc/client/grpc/factory.go
index 0bde30e..d2388f0 100644
--- a/examples/addsvc/client/grpc/factory.go
+++ b/examples/addsvc/client/grpc/factory.go
@@ -13,9 +13,10 @@
 	"github.com/opentracing/opentracing-go"
 )
 
-// SumEndpointFactory transforms GRPC host:port strings into Endpoints that call the Sum method on a GRPC server
+// MakeSumEndpointFactory returns a loadbalancer.Factory that transforms GRPC
+// host:port strings into Endpoints that call the Sum method on a GRPC server
 // at that address.
-func NewSumEndpointFactory(tracer opentracing.Tracer) loadbalancer.Factory {
+func MakeSumEndpointFactory(tracer opentracing.Tracer) loadbalancer.Factory {
 	return func(instance string) (endpoint.Endpoint, io.Closer, error) {
 		cc, err := grpc.Dial(instance, grpc.WithInsecure())
 		return grpctransport.NewClient(
@@ -30,9 +31,10 @@
 	}
 }
 
-// ConcatEndpointFactory transforms GRPC host:port strings into Endpoints that call the Concat method on a GRPC server
-// at that address.
-func NewConcatEndpointFactory(tracer opentracing.Tracer) loadbalancer.Factory {
+// MakeConcatEndpointFactory returns a loadbalancer.Factory that transforms
+// GRPC host:port strings into Endpoints that call the Concat method on a GRPC
+// server at that address.
+func MakeConcatEndpointFactory(tracer opentracing.Tracer) loadbalancer.Factory {
 	return func(instance string) (endpoint.Endpoint, io.Closer, error) {
 		cc, err := grpc.Dial(instance, grpc.WithInsecure())
 		return grpctransport.NewClient(
diff --git a/examples/addsvc/client/httpjson/factory.go b/examples/addsvc/client/httpjson/factory.go
index 10b8564..d5d2bae 100644
--- a/examples/addsvc/client/httpjson/factory.go
+++ b/examples/addsvc/client/httpjson/factory.go
@@ -12,11 +12,11 @@
 	"github.com/opentracing/opentracing-go"
 )
 
-// SumEndpointFactory generates a Factory that transforms an http url into an
-// Endpoint.
+// MakeSumEndpointFactory generates a Factory that transforms an http url into
+// an Endpoint.
 //
 // The path of the url is reset to /sum.
-func NewSumEndpointFactory(tracer opentracing.Tracer) loadbalancer.Factory {
+func MakeSumEndpointFactory(tracer opentracing.Tracer) loadbalancer.Factory {
 	return func(instance string) (endpoint.Endpoint, io.Closer, error) {
 		sumURL, err := url.Parse(instance)
 		if err != nil {
@@ -37,11 +37,11 @@
 	}
 }
 
-// NewConcatEndpointFactory generates a Factory that transforms an http url
+// MakeConcatEndpointFactory generates a Factory that transforms an http url
 // into an Endpoint.
 //
 // The path of the url is reset to /concat.
-func NewConcatEndpointFactory(tracer opentracing.Tracer) loadbalancer.Factory {
+func MakeConcatEndpointFactory(tracer opentracing.Tracer) loadbalancer.Factory {
 	return func(instance string) (endpoint.Endpoint, io.Closer, error) {
 		concatURL, err := url.Parse(instance)
 		if err != nil {
diff --git a/examples/addsvc/client/main.go b/examples/addsvc/client/main.go
index 72b65c2..73b568c 100644
--- a/examples/addsvc/client/main.go
+++ b/examples/addsvc/client/main.go
@@ -85,8 +85,8 @@
 	switch *transport {
 	case "grpc":
 		instances = strings.Split(*grpcAddrs, ",")
-		sumFactory = grpcclient.NewSumEndpointFactory(tracer)
-		concatFactory = grpcclient.NewConcatEndpointFactory(tracer)
+		sumFactory = grpcclient.MakeSumEndpointFactory(tracer)
+		concatFactory = grpcclient.MakeConcatEndpointFactory(tracer)
 
 	case "httpjson":
 		instances = strings.Split(*httpAddrs, ",")
@@ -95,8 +95,8 @@
 				instances[i] = "http://" + rawurl
 			}
 		}
-		sumFactory = httpjsonclient.NewSumEndpointFactory(tracer)
-		concatFactory = httpjsonclient.NewConcatEndpointFactory(tracer)
+		sumFactory = httpjsonclient.MakeSumEndpointFactory(tracer)
+		concatFactory = httpjsonclient.MakeConcatEndpointFactory(tracer)
 
 	case "netrpc":
 		instances = strings.Split(*netrpcAddrs, ",")
diff --git a/examples/addsvc/service.go b/examples/addsvc/service.go
index 258da49..f0531a2 100644
--- a/examples/addsvc/service.go
+++ b/examples/addsvc/service.go
@@ -10,9 +10,7 @@
 
 type pureAddService struct{}
 
-func (pureAddService) Sum(a, b int) int {
-	return a + b
-}
+func (pureAddService) Sum(a, b int) int { return a + b }
 
 func (pureAddService) Concat(a, b string) string { return a + b }
 
diff --git a/examples/apigateway/main.go b/examples/apigateway/main.go
index c881122..c27c47b 100644
--- a/examples/apigateway/main.go
+++ b/examples/apigateway/main.go
@@ -78,8 +78,8 @@
 		factory loadbalancer.Factory
 	}{
 		"addsvc": {
-			{path: "/api/addsvc/concat", factory: grpc.NewConcatEndpointFactory(opentracing.GlobalTracer())},
-			{path: "/api/addsvc/sum", factory: grpc.NewSumEndpointFactory(opentracing.GlobalTracer())},
+			{path: "/api/addsvc/concat", factory: grpc.MakeConcatEndpointFactory(opentracing.GlobalTracer())},
+			{path: "/api/addsvc/sum", factory: grpc.MakeSumEndpointFactory(opentracing.GlobalTracer())},
 		},
 		"stringsvc": {
 			{path: "/api/stringsvc/uppercase", factory: httpFactory(ctx, "GET", "uppercase/")},
diff --git a/tracing/opentracing/endpoint.go b/tracing/opentracing/endpoint.go
index 8757c65..42323fc 100644
--- a/tracing/opentracing/endpoint.go
+++ b/tracing/opentracing/endpoint.go
@@ -3,6 +3,7 @@
 import (
 	"github.com/go-kit/kit/endpoint"
 	"github.com/opentracing/opentracing-go"
+	otext "github.com/opentracing/opentracing-go/ext"
 	"golang.org/x/net/context"
 )
 
@@ -21,7 +22,7 @@
 			} else {
 				serverSpan.SetOperationName(operationName)
 			}
-			serverSpan.SetTag("span.kind", "server")
+			otext.SpanKind.Set(serverSpan, otext.SpanKindRPCServer)
 			ctx = opentracing.ContextWithSpan(ctx, serverSpan)
 			defer serverSpan.Finish()
 			return next(ctx, request)
@@ -39,7 +40,7 @@
 				OperationName: operationName,
 				Parent:        parentSpan, // may be nil
 			})
-			clientSpan.SetTag("span.kind", "client")
+			otext.SpanKind.Set(clientSpan, otext.SpanKindRPCClient)
 			ctx = opentracing.ContextWithSpan(ctx, clientSpan)
 			defer clientSpan.Finish()
 			return next(ctx, request)