diff --git a/clientcompat/internal/clientcompat/clientcompat.twirp.go b/clientcompat/internal/clientcompat/clientcompat.twirp.go
index 36ac7834..f2fd41da 100644
--- a/clientcompat/internal/clientcompat/clientcompat.twirp.go
+++ b/clientcompat/internal/clientcompat/clientcompat.twirp.go
@@ -1,9 +1,9 @@
-// Code generated by protoc-gen-twirp v5.8.0, DO NOT EDIT.
+// Code generated by protoc-gen-twirp v5.9.0, DO NOT EDIT.
 // source: clientcompat.proto
 
 /*
 Package clientcompat is a generated twirp stub package.
-This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.8.0.
+This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.9.0.
 
 It is generated from these files:
 	clientcompat.proto
@@ -469,7 +469,7 @@ func (s *compatServiceServer) ServiceDescriptor() ([]byte, int) {
 }
 
 func (s *compatServiceServer) ProtocGenTwirpVersion() string {
-	return "v5.8.0"
+	return "v5.9.0"
 }
 
 func (s *compatServiceServer) PathPrefix() string {
@@ -610,7 +610,7 @@ func newRequest(ctx context.Context, url string, reqBody io.Reader, contentType
 	}
 	req.Header.Set("Accept", contentType)
 	req.Header.Set("Content-Type", contentType)
-	req.Header.Set("Twirp-Version", "v5.8.0")
+	req.Header.Set("Twirp-Version", "v5.9.0")
 	return req, nil
 }
 
diff --git a/clientcompat/pycompat/clientcompat_pb2_twirp.py b/clientcompat/pycompat/clientcompat_pb2_twirp.py
index d269c80d..c112d52c 100644
--- a/clientcompat/pycompat/clientcompat_pb2_twirp.py
+++ b/clientcompat/pycompat/clientcompat_pb2_twirp.py
@@ -1,4 +1,4 @@
-# Code generated by protoc-gen-twirp_python v5.8.0, DO NOT EDIT.
+# Code generated by protoc-gen-twirp_python v5.9.0, DO NOT EDIT.
 # source: clientcompat.proto
 
 try:
diff --git a/example/service.twirp.go b/example/service.twirp.go
index 01055a9f..d3238254 100644
--- a/example/service.twirp.go
+++ b/example/service.twirp.go
@@ -1,9 +1,9 @@
-// Code generated by protoc-gen-twirp v5.8.0, DO NOT EDIT.
+// Code generated by protoc-gen-twirp v5.9.0, DO NOT EDIT.
 // source: service.proto
 
 /*
 Package example is a generated twirp stub package.
-This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.8.0.
+This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.9.0.
 
 It is generated from these files:
 	service.proto
@@ -311,7 +311,7 @@ func (s *haberdasherServer) ServiceDescriptor() ([]byte, int) {
 }
 
 func (s *haberdasherServer) ProtocGenTwirpVersion() string {
-	return "v5.8.0"
+	return "v5.9.0"
 }
 
 func (s *haberdasherServer) PathPrefix() string {
@@ -452,7 +452,7 @@ func newRequest(ctx context.Context, url string, reqBody io.Reader, contentType
 	}
 	req.Header.Set("Accept", contentType)
 	req.Header.Set("Content-Type", contentType)
-	req.Header.Set("Twirp-Version", "v5.8.0")
+	req.Header.Set("Twirp-Version", "v5.9.0")
 	return req, nil
 }
 
diff --git a/example/service_pb2_twirp.py b/example/service_pb2_twirp.py
index b6a31674..7cc4f985 100644
--- a/example/service_pb2_twirp.py
+++ b/example/service_pb2_twirp.py
@@ -1,4 +1,4 @@
-# Code generated by protoc-gen-twirp_python v5.8.0, DO NOT EDIT.
+# Code generated by protoc-gen-twirp_python v5.9.0, DO NOT EDIT.
 # source: service.proto
 
 try:
diff --git a/internal/gen/version.go b/internal/gen/version.go
index 573c7341..fc71bbe1 100644
--- a/internal/gen/version.go
+++ b/internal/gen/version.go
@@ -13,4 +13,4 @@
 
 package gen
 
-const Version = "v5.8.0"
+const Version = "v5.9.0"
diff --git a/internal/twirptest/empty_service/empty_service.twirp.go b/internal/twirptest/empty_service/empty_service.twirp.go
index a2613695..3b519eac 100644
--- a/internal/twirptest/empty_service/empty_service.twirp.go
+++ b/internal/twirptest/empty_service/empty_service.twirp.go
@@ -1,9 +1,9 @@
-// Code generated by protoc-gen-twirp v5.8.0, DO NOT EDIT.
+// Code generated by protoc-gen-twirp v5.9.0, DO NOT EDIT.
 // source: empty_service.proto
 
 /*
 Package empty_service is a generated twirp stub package.
-This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.8.0.
+This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.9.0.
 
 It is generated from these files:
 	empty_service.proto
@@ -145,7 +145,7 @@ func (s *emptyServer) ServiceDescriptor() ([]byte, int) {
 }
 
 func (s *emptyServer) ProtocGenTwirpVersion() string {
-	return "v5.8.0"
+	return "v5.9.0"
 }
 
 func (s *emptyServer) PathPrefix() string {
@@ -286,7 +286,7 @@ func newRequest(ctx context.Context, url string, reqBody io.Reader, contentType
 	}
 	req.Header.Set("Accept", contentType)
 	req.Header.Set("Content-Type", contentType)
-	req.Header.Set("Twirp-Version", "v5.8.0")
+	req.Header.Set("Twirp-Version", "v5.9.0")
 	return req, nil
 }
 
diff --git a/internal/twirptest/empty_service/empty_service_pb2_twirp.py b/internal/twirptest/empty_service/empty_service_pb2_twirp.py
index 23c1a121..6ddba043 100644
--- a/internal/twirptest/empty_service/empty_service_pb2_twirp.py
+++ b/internal/twirptest/empty_service/empty_service_pb2_twirp.py
@@ -1,4 +1,4 @@
-# Code generated by protoc-gen-twirp_python v5.8.0, DO NOT EDIT.
+# Code generated by protoc-gen-twirp_python v5.9.0, DO NOT EDIT.
 # source: empty_service.proto
 
 try:
diff --git a/internal/twirptest/gogo_compat/service.twirp.go b/internal/twirptest/gogo_compat/service.twirp.go
index 84a74c6e..973c23fd 100644
--- a/internal/twirptest/gogo_compat/service.twirp.go
+++ b/internal/twirptest/gogo_compat/service.twirp.go
@@ -1,9 +1,9 @@
-// Code generated by protoc-gen-twirp v5.8.0, DO NOT EDIT.
+// Code generated by protoc-gen-twirp v5.9.0, DO NOT EDIT.
 // source: service.proto
 
 /*
 Package gogo_compat is a generated twirp stub package.
-This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.8.0.
+This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.9.0.
 
 Test to make sure that Twirp plays well with code generated with
 github.com/gogo/protobuf/protoc-gen-gofast.
@@ -313,7 +313,7 @@ func (s *svcServer) ServiceDescriptor() ([]byte, int) {
 }
 
 func (s *svcServer) ProtocGenTwirpVersion() string {
-	return "v5.8.0"
+	return "v5.9.0"
 }
 
 func (s *svcServer) PathPrefix() string {
@@ -454,7 +454,7 @@ func newRequest(ctx context.Context, url string, reqBody io.Reader, contentType
 	}
 	req.Header.Set("Accept", contentType)
 	req.Header.Set("Content-Type", contentType)
-	req.Header.Set("Twirp-Version", "v5.8.0")
+	req.Header.Set("Twirp-Version", "v5.9.0")
 	return req, nil
 }
 
diff --git a/internal/twirptest/google_protobuf_imports/service.twirp.go b/internal/twirptest/google_protobuf_imports/service.twirp.go
index 811b5f85..fdea0903 100644
--- a/internal/twirptest/google_protobuf_imports/service.twirp.go
+++ b/internal/twirptest/google_protobuf_imports/service.twirp.go
@@ -1,9 +1,9 @@
-// Code generated by protoc-gen-twirp v5.8.0, DO NOT EDIT.
+// Code generated by protoc-gen-twirp v5.9.0, DO NOT EDIT.
 // source: service.proto
 
 /*
 Package google_protobuf_imports is a generated twirp stub package.
-This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.8.0.
+This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.9.0.
 
 It is generated from these files:
 	service.proto
@@ -312,7 +312,7 @@ func (s *svcServer) ServiceDescriptor() ([]byte, int) {
 }
 
 func (s *svcServer) ProtocGenTwirpVersion() string {
-	return "v5.8.0"
+	return "v5.9.0"
 }
 
 func (s *svcServer) PathPrefix() string {
@@ -453,7 +453,7 @@ func newRequest(ctx context.Context, url string, reqBody io.Reader, contentType
 	}
 	req.Header.Set("Accept", contentType)
 	req.Header.Set("Content-Type", contentType)
-	req.Header.Set("Twirp-Version", "v5.8.0")
+	req.Header.Set("Twirp-Version", "v5.9.0")
 	return req, nil
 }
 
diff --git a/internal/twirptest/google_protobuf_imports/service_pb2_twirp.py b/internal/twirptest/google_protobuf_imports/service_pb2_twirp.py
index 73f230c9..ed999753 100644
--- a/internal/twirptest/google_protobuf_imports/service_pb2_twirp.py
+++ b/internal/twirptest/google_protobuf_imports/service_pb2_twirp.py
@@ -1,4 +1,4 @@
-# Code generated by protoc-gen-twirp_python v5.8.0, DO NOT EDIT.
+# Code generated by protoc-gen-twirp_python v5.9.0, DO NOT EDIT.
 # source: service.proto
 
 try:
diff --git a/internal/twirptest/importable/importable.twirp.go b/internal/twirptest/importable/importable.twirp.go
index 69153b33..7311d22f 100644
--- a/internal/twirptest/importable/importable.twirp.go
+++ b/internal/twirptest/importable/importable.twirp.go
@@ -1,9 +1,9 @@
-// Code generated by protoc-gen-twirp v5.8.0, DO NOT EDIT.
+// Code generated by protoc-gen-twirp v5.9.0, DO NOT EDIT.
 // source: importable.proto
 
 /*
 Package importable is a generated twirp stub package.
-This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.8.0.
+This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.9.0.
 
 Test to make sure that importing other packages doesnt break
 
@@ -312,7 +312,7 @@ func (s *svcServer) ServiceDescriptor() ([]byte, int) {
 }
 
 func (s *svcServer) ProtocGenTwirpVersion() string {
-	return "v5.8.0"
+	return "v5.9.0"
 }
 
 func (s *svcServer) PathPrefix() string {
@@ -453,7 +453,7 @@ func newRequest(ctx context.Context, url string, reqBody io.Reader, contentType
 	}
 	req.Header.Set("Accept", contentType)
 	req.Header.Set("Content-Type", contentType)
-	req.Header.Set("Twirp-Version", "v5.8.0")
+	req.Header.Set("Twirp-Version", "v5.9.0")
 	return req, nil
 }
 
diff --git a/internal/twirptest/importable/importable_pb2_twirp.py b/internal/twirptest/importable/importable_pb2_twirp.py
index 54a95d25..156817a3 100644
--- a/internal/twirptest/importable/importable_pb2_twirp.py
+++ b/internal/twirptest/importable/importable_pb2_twirp.py
@@ -1,4 +1,4 @@
-# Code generated by protoc-gen-twirp_python v5.8.0, DO NOT EDIT.
+# Code generated by protoc-gen-twirp_python v5.9.0, DO NOT EDIT.
 # source: importable.proto
 
 try:
diff --git a/internal/twirptest/importer/importer.twirp.go b/internal/twirptest/importer/importer.twirp.go
index 5c2a5dd1..2c512476 100644
--- a/internal/twirptest/importer/importer.twirp.go
+++ b/internal/twirptest/importer/importer.twirp.go
@@ -1,9 +1,9 @@
-// Code generated by protoc-gen-twirp v5.8.0, DO NOT EDIT.
+// Code generated by protoc-gen-twirp v5.9.0, DO NOT EDIT.
 // source: importer.proto
 
 /*
 Package importer is a generated twirp stub package.
-This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.8.0.
+This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.9.0.
 
 Test to make sure that importing other packages doesnt break
 
@@ -314,7 +314,7 @@ func (s *svc2Server) ServiceDescriptor() ([]byte, int) {
 }
 
 func (s *svc2Server) ProtocGenTwirpVersion() string {
-	return "v5.8.0"
+	return "v5.9.0"
 }
 
 func (s *svc2Server) PathPrefix() string {
@@ -455,7 +455,7 @@ func newRequest(ctx context.Context, url string, reqBody io.Reader, contentType
 	}
 	req.Header.Set("Accept", contentType)
 	req.Header.Set("Content-Type", contentType)
-	req.Header.Set("Twirp-Version", "v5.8.0")
+	req.Header.Set("Twirp-Version", "v5.9.0")
 	return req, nil
 }
 
diff --git a/internal/twirptest/importer/importer_pb2_twirp.py b/internal/twirptest/importer/importer_pb2_twirp.py
index 00a15470..359aadfd 100644
--- a/internal/twirptest/importer/importer_pb2_twirp.py
+++ b/internal/twirptest/importer/importer_pb2_twirp.py
@@ -1,4 +1,4 @@
-# Code generated by protoc-gen-twirp_python v5.8.0, DO NOT EDIT.
+# Code generated by protoc-gen-twirp_python v5.9.0, DO NOT EDIT.
 # source: importer.proto
 
 try:
diff --git a/internal/twirptest/importmapping/x/x.twirp.go b/internal/twirptest/importmapping/x/x.twirp.go
index b766e94b..5ceeea78 100644
--- a/internal/twirptest/importmapping/x/x.twirp.go
+++ b/internal/twirptest/importmapping/x/x.twirp.go
@@ -1,9 +1,9 @@
-// Code generated by protoc-gen-twirp v5.8.0, DO NOT EDIT.
+// Code generated by protoc-gen-twirp v5.9.0, DO NOT EDIT.
 // source: x/x.proto
 
 /*
 Package x is a generated twirp stub package.
-This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.8.0.
+This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.9.0.
 
 It is generated from these files:
 	x/x.proto
@@ -311,7 +311,7 @@ func (s *svc1Server) ServiceDescriptor() ([]byte, int) {
 }
 
 func (s *svc1Server) ProtocGenTwirpVersion() string {
-	return "v5.8.0"
+	return "v5.9.0"
 }
 
 func (s *svc1Server) PathPrefix() string {
@@ -452,7 +452,7 @@ func newRequest(ctx context.Context, url string, reqBody io.Reader, contentType
 	}
 	req.Header.Set("Accept", contentType)
 	req.Header.Set("Content-Type", contentType)
-	req.Header.Set("Twirp-Version", "v5.8.0")
+	req.Header.Set("Twirp-Version", "v5.9.0")
 	return req, nil
 }
 
diff --git a/internal/twirptest/importmapping/x/x_pb2_twirp.py b/internal/twirptest/importmapping/x/x_pb2_twirp.py
index 49e35dc8..db4e4e2a 100644
--- a/internal/twirptest/importmapping/x/x_pb2_twirp.py
+++ b/internal/twirptest/importmapping/x/x_pb2_twirp.py
@@ -1,4 +1,4 @@
-# Code generated by protoc-gen-twirp_python v5.8.0, DO NOT EDIT.
+# Code generated by protoc-gen-twirp_python v5.9.0, DO NOT EDIT.
 # source: x/x.proto
 
 try:
diff --git a/internal/twirptest/importmapping/y/y_pb2_twirp.py b/internal/twirptest/importmapping/y/y_pb2_twirp.py
index caa9300b..6229a103 100644
--- a/internal/twirptest/importmapping/y/y_pb2_twirp.py
+++ b/internal/twirptest/importmapping/y/y_pb2_twirp.py
@@ -1,4 +1,4 @@
-# Code generated by protoc-gen-twirp_python v5.8.0, DO NOT EDIT.
+# Code generated by protoc-gen-twirp_python v5.9.0, DO NOT EDIT.
 # source: y/y.proto
 
 try:
diff --git a/internal/twirptest/multiple/multiple1.twirp.go b/internal/twirptest/multiple/multiple1.twirp.go
index 420efa4a..134b79d3 100644
--- a/internal/twirptest/multiple/multiple1.twirp.go
+++ b/internal/twirptest/multiple/multiple1.twirp.go
@@ -1,9 +1,9 @@
-// Code generated by protoc-gen-twirp v5.8.0, DO NOT EDIT.
+// Code generated by protoc-gen-twirp v5.9.0, DO NOT EDIT.
 // source: multiple1.proto
 
 /*
 Package multiple is a generated twirp stub package.
-This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.8.0.
+This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.9.0.
 
 test to make sure that multiple proto files in one package works
 
@@ -313,7 +313,7 @@ func (s *svc1Server) ServiceDescriptor() ([]byte, int) {
 }
 
 func (s *svc1Server) ProtocGenTwirpVersion() string {
-	return "v5.8.0"
+	return "v5.9.0"
 }
 
 func (s *svc1Server) PathPrefix() string {
@@ -454,7 +454,7 @@ func newRequest(ctx context.Context, url string, reqBody io.Reader, contentType
 	}
 	req.Header.Set("Accept", contentType)
 	req.Header.Set("Content-Type", contentType)
-	req.Header.Set("Twirp-Version", "v5.8.0")
+	req.Header.Set("Twirp-Version", "v5.9.0")
 	return req, nil
 }
 
diff --git a/internal/twirptest/multiple/multiple1_pb2_twirp.py b/internal/twirptest/multiple/multiple1_pb2_twirp.py
index 4a07ffd0..969a3258 100644
--- a/internal/twirptest/multiple/multiple1_pb2_twirp.py
+++ b/internal/twirptest/multiple/multiple1_pb2_twirp.py
@@ -1,4 +1,4 @@
-# Code generated by protoc-gen-twirp_python v5.8.0, DO NOT EDIT.
+# Code generated by protoc-gen-twirp_python v5.9.0, DO NOT EDIT.
 # source: multiple1.proto
 
 try:
diff --git a/internal/twirptest/multiple/multiple2.twirp.go b/internal/twirptest/multiple/multiple2.twirp.go
index 138a93d2..2423dafb 100644
--- a/internal/twirptest/multiple/multiple2.twirp.go
+++ b/internal/twirptest/multiple/multiple2.twirp.go
@@ -1,4 +1,4 @@
-// Code generated by protoc-gen-twirp v5.8.0, DO NOT EDIT.
+// Code generated by protoc-gen-twirp v5.9.0, DO NOT EDIT.
 // source: multiple2.proto
 
 package multiple
@@ -457,7 +457,7 @@ func (s *svc2Server) ServiceDescriptor() ([]byte, int) {
 }
 
 func (s *svc2Server) ProtocGenTwirpVersion() string {
-	return "v5.8.0"
+	return "v5.9.0"
 }
 
 func (s *svc2Server) PathPrefix() string {
diff --git a/internal/twirptest/multiple/multiple2_pb2_twirp.py b/internal/twirptest/multiple/multiple2_pb2_twirp.py
index 78f9836d..9edbfa2f 100644
--- a/internal/twirptest/multiple/multiple2_pb2_twirp.py
+++ b/internal/twirptest/multiple/multiple2_pb2_twirp.py
@@ -1,4 +1,4 @@
-# Code generated by protoc-gen-twirp_python v5.8.0, DO NOT EDIT.
+# Code generated by protoc-gen-twirp_python v5.9.0, DO NOT EDIT.
 # source: multiple2.proto
 
 try:
diff --git a/internal/twirptest/no_package_name/no_package_name.twirp.go b/internal/twirptest/no_package_name/no_package_name.twirp.go
index 4835dfd1..c5fe12e2 100644
--- a/internal/twirptest/no_package_name/no_package_name.twirp.go
+++ b/internal/twirptest/no_package_name/no_package_name.twirp.go
@@ -1,9 +1,9 @@
-// Code generated by protoc-gen-twirp v5.8.0, DO NOT EDIT.
+// Code generated by protoc-gen-twirp v5.9.0, DO NOT EDIT.
 // source: no_package_name.proto
 
 /*
 Package no_package_name is a generated twirp stub package.
-This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.8.0.
+This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.9.0.
 
 It is generated from these files:
 	no_package_name.proto
@@ -309,7 +309,7 @@ func (s *svcServer) ServiceDescriptor() ([]byte, int) {
 }
 
 func (s *svcServer) ProtocGenTwirpVersion() string {
-	return "v5.8.0"
+	return "v5.9.0"
 }
 
 func (s *svcServer) PathPrefix() string {
@@ -450,7 +450,7 @@ func newRequest(ctx context.Context, url string, reqBody io.Reader, contentType
 	}
 	req.Header.Set("Accept", contentType)
 	req.Header.Set("Content-Type", contentType)
-	req.Header.Set("Twirp-Version", "v5.8.0")
+	req.Header.Set("Twirp-Version", "v5.9.0")
 	return req, nil
 }
 
diff --git a/internal/twirptest/no_package_name/no_package_name_pb2_twirp.py b/internal/twirptest/no_package_name/no_package_name_pb2_twirp.py
index 13a8ab0d..d6c7e110 100644
--- a/internal/twirptest/no_package_name/no_package_name_pb2_twirp.py
+++ b/internal/twirptest/no_package_name/no_package_name_pb2_twirp.py
@@ -1,4 +1,4 @@
-# Code generated by protoc-gen-twirp_python v5.8.0, DO NOT EDIT.
+# Code generated by protoc-gen-twirp_python v5.9.0, DO NOT EDIT.
 # source: no_package_name.proto
 
 try:
diff --git a/internal/twirptest/no_package_name_importer/no_package_name_importer.twirp.go b/internal/twirptest/no_package_name_importer/no_package_name_importer.twirp.go
index c2da1434..823dd9d7 100644
--- a/internal/twirptest/no_package_name_importer/no_package_name_importer.twirp.go
+++ b/internal/twirptest/no_package_name_importer/no_package_name_importer.twirp.go
@@ -1,9 +1,9 @@
-// Code generated by protoc-gen-twirp v5.8.0, DO NOT EDIT.
+// Code generated by protoc-gen-twirp v5.9.0, DO NOT EDIT.
 // source: no_package_name_importer.proto
 
 /*
 Package no_package_name_importer is a generated twirp stub package.
-This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.8.0.
+This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.9.0.
 
 It is generated from these files:
 	no_package_name_importer.proto
@@ -311,7 +311,7 @@ func (s *svc2Server) ServiceDescriptor() ([]byte, int) {
 }
 
 func (s *svc2Server) ProtocGenTwirpVersion() string {
-	return "v5.8.0"
+	return "v5.9.0"
 }
 
 func (s *svc2Server) PathPrefix() string {
@@ -452,7 +452,7 @@ func newRequest(ctx context.Context, url string, reqBody io.Reader, contentType
 	}
 	req.Header.Set("Accept", contentType)
 	req.Header.Set("Content-Type", contentType)
-	req.Header.Set("Twirp-Version", "v5.8.0")
+	req.Header.Set("Twirp-Version", "v5.9.0")
 	return req, nil
 }
 
diff --git a/internal/twirptest/no_package_name_importer/no_package_name_importer_pb2_twirp.py b/internal/twirptest/no_package_name_importer/no_package_name_importer_pb2_twirp.py
index 63717b9f..3027814f 100644
--- a/internal/twirptest/no_package_name_importer/no_package_name_importer_pb2_twirp.py
+++ b/internal/twirptest/no_package_name_importer/no_package_name_importer_pb2_twirp.py
@@ -1,4 +1,4 @@
-# Code generated by protoc-gen-twirp_python v5.8.0, DO NOT EDIT.
+# Code generated by protoc-gen-twirp_python v5.9.0, DO NOT EDIT.
 # source: no_package_name_importer.proto
 
 try:
diff --git a/internal/twirptest/proto/proto.twirp.go b/internal/twirptest/proto/proto.twirp.go
index 2d25c229..573d9f7e 100644
--- a/internal/twirptest/proto/proto.twirp.go
+++ b/internal/twirptest/proto/proto.twirp.go
@@ -1,9 +1,9 @@
-// Code generated by protoc-gen-twirp v5.8.0, DO NOT EDIT.
+// Code generated by protoc-gen-twirp v5.9.0, DO NOT EDIT.
 // source: proto.proto
 
 /*
 Package proto is a generated twirp stub package.
-This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.8.0.
+This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.9.0.
 
 Test to make sure that a package named proto doesn't break
 
@@ -312,7 +312,7 @@ func (s *svcServer) ServiceDescriptor() ([]byte, int) {
 }
 
 func (s *svcServer) ProtocGenTwirpVersion() string {
-	return "v5.8.0"
+	return "v5.9.0"
 }
 
 func (s *svcServer) PathPrefix() string {
@@ -453,7 +453,7 @@ func newRequest(ctx context.Context, url string, reqBody io.Reader, contentType
 	}
 	req.Header.Set("Accept", contentType)
 	req.Header.Set("Content-Type", contentType)
-	req.Header.Set("Twirp-Version", "v5.8.0")
+	req.Header.Set("Twirp-Version", "v5.9.0")
 	return req, nil
 }
 
diff --git a/internal/twirptest/proto/proto_pb2_twirp.py b/internal/twirptest/proto/proto_pb2_twirp.py
index 432f06ee..ad294d7e 100644
--- a/internal/twirptest/proto/proto_pb2_twirp.py
+++ b/internal/twirptest/proto/proto_pb2_twirp.py
@@ -1,4 +1,4 @@
-# Code generated by protoc-gen-twirp_python v5.8.0, DO NOT EDIT.
+# Code generated by protoc-gen-twirp_python v5.9.0, DO NOT EDIT.
 # source: proto.proto
 
 try:
diff --git a/internal/twirptest/service.twirp.go b/internal/twirptest/service.twirp.go
index 659552c2..6722f53a 100644
--- a/internal/twirptest/service.twirp.go
+++ b/internal/twirptest/service.twirp.go
@@ -1,9 +1,9 @@
-// Code generated by protoc-gen-twirp v5.8.0, DO NOT EDIT.
+// Code generated by protoc-gen-twirp v5.9.0, DO NOT EDIT.
 // source: service.proto
 
 /*
 Package twirptest is a generated twirp stub package.
-This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.8.0.
+This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.9.0.
 
 It is generated from these files:
 	service.proto
@@ -311,7 +311,7 @@ func (s *haberdasherServer) ServiceDescriptor() ([]byte, int) {
 }
 
 func (s *haberdasherServer) ProtocGenTwirpVersion() string {
-	return "v5.8.0"
+	return "v5.9.0"
 }
 
 func (s *haberdasherServer) PathPrefix() string {
@@ -452,7 +452,7 @@ func newRequest(ctx context.Context, url string, reqBody io.Reader, contentType
 	}
 	req.Header.Set("Accept", contentType)
 	req.Header.Set("Content-Type", contentType)
-	req.Header.Set("Twirp-Version", "v5.8.0")
+	req.Header.Set("Twirp-Version", "v5.9.0")
 	return req, nil
 }
 
diff --git a/internal/twirptest/service_method_same_name/service_method_same_name.twirp.go b/internal/twirptest/service_method_same_name/service_method_same_name.twirp.go
index 97a874cf..ee1e598d 100644
--- a/internal/twirptest/service_method_same_name/service_method_same_name.twirp.go
+++ b/internal/twirptest/service_method_same_name/service_method_same_name.twirp.go
@@ -1,9 +1,9 @@
-// Code generated by protoc-gen-twirp v5.8.0, DO NOT EDIT.
+// Code generated by protoc-gen-twirp v5.9.0, DO NOT EDIT.
 // source: service_method_same_name.proto
 
 /*
 Package service_method_same_name is a generated twirp stub package.
-This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.8.0.
+This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.9.0.
 
 It is generated from these files:
 	service_method_same_name.proto
@@ -309,7 +309,7 @@ func (s *echoServer) ServiceDescriptor() ([]byte, int) {
 }
 
 func (s *echoServer) ProtocGenTwirpVersion() string {
-	return "v5.8.0"
+	return "v5.9.0"
 }
 
 func (s *echoServer) PathPrefix() string {
@@ -450,7 +450,7 @@ func newRequest(ctx context.Context, url string, reqBody io.Reader, contentType
 	}
 	req.Header.Set("Accept", contentType)
 	req.Header.Set("Content-Type", contentType)
-	req.Header.Set("Twirp-Version", "v5.8.0")
+	req.Header.Set("Twirp-Version", "v5.9.0")
 	return req, nil
 }
 
diff --git a/internal/twirptest/service_method_same_name/service_method_same_name_pb2_twirp.py b/internal/twirptest/service_method_same_name/service_method_same_name_pb2_twirp.py
index 30ccdccd..e29e5ac3 100644
--- a/internal/twirptest/service_method_same_name/service_method_same_name_pb2_twirp.py
+++ b/internal/twirptest/service_method_same_name/service_method_same_name_pb2_twirp.py
@@ -1,4 +1,4 @@
-# Code generated by protoc-gen-twirp_python v5.8.0, DO NOT EDIT.
+# Code generated by protoc-gen-twirp_python v5.9.0, DO NOT EDIT.
 # source: service_method_same_name.proto
 
 try:
diff --git a/internal/twirptest/service_pb2_twirp.py b/internal/twirptest/service_pb2_twirp.py
index c7a24a8f..1a0f3ee4 100644
--- a/internal/twirptest/service_pb2_twirp.py
+++ b/internal/twirptest/service_pb2_twirp.py
@@ -1,4 +1,4 @@
-# Code generated by protoc-gen-twirp_python v5.8.0, DO NOT EDIT.
+# Code generated by protoc-gen-twirp_python v5.9.0, DO NOT EDIT.
 # source: service.proto
 
 try:
diff --git a/internal/twirptest/snake_case_names/snake_case_names.twirp.go b/internal/twirptest/snake_case_names/snake_case_names.twirp.go
index 21a24c42..5797ace7 100644
--- a/internal/twirptest/snake_case_names/snake_case_names.twirp.go
+++ b/internal/twirptest/snake_case_names/snake_case_names.twirp.go
@@ -1,9 +1,9 @@
-// Code generated by protoc-gen-twirp v5.8.0, DO NOT EDIT.
+// Code generated by protoc-gen-twirp v5.9.0, DO NOT EDIT.
 // source: snake_case_names.proto
 
 /*
 Package snake_case_names is a generated twirp stub package.
-This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.8.0.
+This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.9.0.
 
 Test that protoc-gen-twirp follows the same behavior as protoc-gen-go
 for converting RPCs and message names from snake case to camel case.
@@ -314,7 +314,7 @@ func (s *haberdasherServer) ServiceDescriptor() ([]byte, int) {
 }
 
 func (s *haberdasherServer) ProtocGenTwirpVersion() string {
-	return "v5.8.0"
+	return "v5.9.0"
 }
 
 func (s *haberdasherServer) PathPrefix() string {
@@ -455,7 +455,7 @@ func newRequest(ctx context.Context, url string, reqBody io.Reader, contentType
 	}
 	req.Header.Set("Accept", contentType)
 	req.Header.Set("Content-Type", contentType)
-	req.Header.Set("Twirp-Version", "v5.8.0")
+	req.Header.Set("Twirp-Version", "v5.9.0")
 	return req, nil
 }
 
diff --git a/internal/twirptest/snake_case_names/snake_case_names_pb2_twirp.py b/internal/twirptest/snake_case_names/snake_case_names_pb2_twirp.py
index 4db8d42a..a5bd60fa 100644
--- a/internal/twirptest/snake_case_names/snake_case_names_pb2_twirp.py
+++ b/internal/twirptest/snake_case_names/snake_case_names_pb2_twirp.py
@@ -1,4 +1,4 @@
-# Code generated by protoc-gen-twirp_python v5.8.0, DO NOT EDIT.
+# Code generated by protoc-gen-twirp_python v5.9.0, DO NOT EDIT.
 # source: snake_case_names.proto
 
 try:
diff --git a/internal/twirptest/source_relative/source_relative.twirp.go b/internal/twirptest/source_relative/source_relative.twirp.go
index 793102d1..09fc09b8 100644
--- a/internal/twirptest/source_relative/source_relative.twirp.go
+++ b/internal/twirptest/source_relative/source_relative.twirp.go
@@ -1,9 +1,9 @@
-// Code generated by protoc-gen-twirp v5.8.0, DO NOT EDIT.
+// Code generated by protoc-gen-twirp v5.9.0, DO NOT EDIT.
 // source: source_relative.proto
 
 /*
 Package source_relative is a generated twirp stub package.
-This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.8.0.
+This code was generated with github.com/twitchtv/twirp/protoc-gen-twirp v5.9.0.
 
 It is generated from these files:
 	source_relative.proto
@@ -309,7 +309,7 @@ func (s *svcServer) ServiceDescriptor() ([]byte, int) {
 }
 
 func (s *svcServer) ProtocGenTwirpVersion() string {
-	return "v5.8.0"
+	return "v5.9.0"
 }
 
 func (s *svcServer) PathPrefix() string {
@@ -450,7 +450,7 @@ func newRequest(ctx context.Context, url string, reqBody io.Reader, contentType
 	}
 	req.Header.Set("Accept", contentType)
 	req.Header.Set("Content-Type", contentType)
-	req.Header.Set("Twirp-Version", "v5.8.0")
+	req.Header.Set("Twirp-Version", "v5.9.0")
 	return req, nil
 }
 
diff --git a/internal/twirptest/source_relative/source_relative_pb2_twirp.py b/internal/twirptest/source_relative/source_relative_pb2_twirp.py
index 77a188b3..67fa904c 100644
--- a/internal/twirptest/source_relative/source_relative_pb2_twirp.py
+++ b/internal/twirptest/source_relative/source_relative_pb2_twirp.py
@@ -1,4 +1,4 @@
-# Code generated by protoc-gen-twirp_python v5.8.0, DO NOT EDIT.
+# Code generated by protoc-gen-twirp_python v5.9.0, DO NOT EDIT.
 # source: source_relative.proto
 
 try: