diff --git a/client/compliance_client.go b/client/compliance_client.go
index 2eee17e30..277f3d08d 100644
--- a/client/compliance_client.go
+++ b/client/compliance_client.go
@@ -75,6 +75,7 @@ func defaultComplianceGRPCClientOptions() []option.ClientOption {
 		internaloption.WithDefaultAudience("https://localhost/"),
 		internaloption.WithDefaultScopes(DefaultAuthScopes()...),
 		internaloption.EnableJwtWithScope(),
+		internaloption.EnableNewAuthLibrary(),
 		option.WithGRPCDialOption(grpc.WithDefaultCallOptions(
 			grpc.MaxCallRecvMsgSize(math.MaxInt32))),
 	}
@@ -433,6 +434,7 @@ func defaultComplianceRESTClientOptions() []option.ClientOption {
 		internaloption.WithDefaultUniverseDomain("googleapis.com"),
 		internaloption.WithDefaultAudience("https://localhost/"),
 		internaloption.WithDefaultScopes(DefaultAuthScopes()...),
+		internaloption.EnableNewAuthLibrary(),
 	}
 }
 
diff --git a/client/echo_client.go b/client/echo_client.go
index ffc21c5d7..7e39e532b 100644
--- a/client/echo_client.go
+++ b/client/echo_client.go
@@ -85,6 +85,7 @@ func defaultEchoGRPCClientOptions() []option.ClientOption {
 		internaloption.WithDefaultAudience("https://localhost/"),
 		internaloption.WithDefaultScopes(DefaultAuthScopes()...),
 		internaloption.EnableJwtWithScope(),
+		internaloption.EnableNewAuthLibrary(),
 		option.WithGRPCDialOption(grpc.WithDefaultCallOptions(
 			grpc.MaxCallRecvMsgSize(math.MaxInt32))),
 	}
@@ -599,6 +600,7 @@ func defaultEchoRESTClientOptions() []option.ClientOption {
 		internaloption.WithDefaultUniverseDomain("googleapis.com"),
 		internaloption.WithDefaultAudience("https://localhost/"),
 		internaloption.WithDefaultScopes(DefaultAuthScopes()...),
+		internaloption.EnableNewAuthLibrary(),
 	}
 }
 
diff --git a/client/identity_client.go b/client/identity_client.go
index 1bdd19e7e..3161d5421 100644
--- a/client/identity_client.go
+++ b/client/identity_client.go
@@ -72,6 +72,7 @@ func defaultIdentityGRPCClientOptions() []option.ClientOption {
 		internaloption.WithDefaultAudience("https://localhost/"),
 		internaloption.WithDefaultScopes(DefaultAuthScopes()...),
 		internaloption.EnableJwtWithScope(),
+		internaloption.EnableNewAuthLibrary(),
 		option.WithGRPCDialOption(grpc.WithDefaultCallOptions(
 			grpc.MaxCallRecvMsgSize(math.MaxInt32))),
 	}
@@ -414,6 +415,7 @@ func defaultIdentityRESTClientOptions() []option.ClientOption {
 		internaloption.WithDefaultUniverseDomain("googleapis.com"),
 		internaloption.WithDefaultAudience("https://localhost/"),
 		internaloption.WithDefaultScopes(DefaultAuthScopes()...),
+		internaloption.EnableNewAuthLibrary(),
 	}
 }
 
@@ -887,11 +889,11 @@ func (c *identityRESTClient) UpdateUser(ctx context.Context, req *genprotopb.Upd
 
 	params := url.Values{}
 	if req.GetUpdateMask() != nil {
-		updateMask, err := protojson.Marshal(req.GetUpdateMask())
+		field, err := protojson.Marshal(req.GetUpdateMask())
 		if err != nil {
 			return nil, err
 		}
-		params.Add("updateMask", string(updateMask[1:len(updateMask)-1]))
+		params.Add("updateMask", string(field[1:len(field)-1]))
 	}
 
 	baseUrl.RawQuery = params.Encode()
diff --git a/client/messaging_client.go b/client/messaging_client.go
index e9accde1b..9f8279675 100644
--- a/client/messaging_client.go
+++ b/client/messaging_client.go
@@ -85,6 +85,7 @@ func defaultMessagingGRPCClientOptions() []option.ClientOption {
 		internaloption.WithDefaultAudience("https://localhost/"),
 		internaloption.WithDefaultScopes(DefaultAuthScopes()...),
 		internaloption.EnableJwtWithScope(),
+		internaloption.EnableNewAuthLibrary(),
 		option.WithGRPCDialOption(grpc.WithDefaultCallOptions(
 			grpc.MaxCallRecvMsgSize(math.MaxInt32))),
 	}
@@ -684,6 +685,7 @@ func defaultMessagingRESTClientOptions() []option.ClientOption {
 		internaloption.WithDefaultUniverseDomain("googleapis.com"),
 		internaloption.WithDefaultAudience("https://localhost/"),
 		internaloption.WithDefaultScopes(DefaultAuthScopes()...),
+		internaloption.EnableNewAuthLibrary(),
 	}
 }
 
@@ -1339,11 +1341,11 @@ func (c *messagingRESTClient) UpdateRoom(ctx context.Context, req *genprotopb.Up
 
 	params := url.Values{}
 	if req.GetUpdateMask() != nil {
-		updateMask, err := protojson.Marshal(req.GetUpdateMask())
+		field, err := protojson.Marshal(req.GetUpdateMask())
 		if err != nil {
 			return nil, err
 		}
-		params.Add("updateMask", string(updateMask[1:len(updateMask)-1]))
+		params.Add("updateMask", string(field[1:len(field)-1]))
 	}
 
 	baseUrl.RawQuery = params.Encode()
@@ -1655,11 +1657,11 @@ func (c *messagingRESTClient) UpdateBlurb(ctx context.Context, req *genprotopb.U
 
 	params := url.Values{}
 	if req.GetUpdateMask() != nil {
-		updateMask, err := protojson.Marshal(req.GetUpdateMask())
+		field, err := protojson.Marshal(req.GetUpdateMask())
 		if err != nil {
 			return nil, err
 		}
-		params.Add("updateMask", string(updateMask[1:len(updateMask)-1]))
+		params.Add("updateMask", string(field[1:len(field)-1]))
 	}
 
 	baseUrl.RawQuery = params.Encode()
diff --git a/client/sequence_client.go b/client/sequence_client.go
index 0ae81421b..8c83b58ee 100644
--- a/client/sequence_client.go
+++ b/client/sequence_client.go
@@ -75,6 +75,7 @@ func defaultSequenceGRPCClientOptions() []option.ClientOption {
 		internaloption.WithDefaultAudience("https://localhost/"),
 		internaloption.WithDefaultScopes(DefaultAuthScopes()...),
 		internaloption.EnableJwtWithScope(),
+		internaloption.EnableNewAuthLibrary(),
 		option.WithGRPCDialOption(grpc.WithDefaultCallOptions(
 			grpc.MaxCallRecvMsgSize(math.MaxInt32))),
 	}
@@ -414,6 +415,7 @@ func defaultSequenceRESTClientOptions() []option.ClientOption {
 		internaloption.WithDefaultUniverseDomain("googleapis.com"),
 		internaloption.WithDefaultAudience("https://localhost/"),
 		internaloption.WithDefaultScopes(DefaultAuthScopes()...),
+		internaloption.EnableNewAuthLibrary(),
 	}
 }
 
diff --git a/client/testing_client.go b/client/testing_client.go
index 85ef96cea..828212017 100644
--- a/client/testing_client.go
+++ b/client/testing_client.go
@@ -73,6 +73,7 @@ func defaultTestingGRPCClientOptions() []option.ClientOption {
 		internaloption.WithDefaultAudience("https://localhost/"),
 		internaloption.WithDefaultScopes(DefaultAuthScopes()...),
 		internaloption.EnableJwtWithScope(),
+		internaloption.EnableNewAuthLibrary(),
 		option.WithGRPCDialOption(grpc.WithDefaultCallOptions(
 			grpc.MaxCallRecvMsgSize(math.MaxInt32))),
 	}
@@ -426,6 +427,7 @@ func defaultTestingRESTClientOptions() []option.ClientOption {
 		internaloption.WithDefaultUniverseDomain("googleapis.com"),
 		internaloption.WithDefaultAudience("https://localhost/"),
 		internaloption.WithDefaultScopes(DefaultAuthScopes()...),
+		internaloption.EnableNewAuthLibrary(),
 	}
 }