diff --git a/internal/fixtures/protobuf.pb.go b/internal/fixtures/protobuf.pb.go
index 9b6f5a96..67273ebe 100644
--- a/internal/fixtures/protobuf.pb.go
+++ b/internal/fixtures/protobuf.pb.go
@@ -1,7 +1,7 @@
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // versions:
-// 	protoc-gen-go v1.30.0
-// 	protoc        v3.21.12
+// 	protoc-gen-go v1.31.0
+// 	protoc        v4.23.4
 // source: github.com/dogmatiq/testkit/internal/fixtures/protobuf.proto
 
 package fixtures