diff --git a/CHANGELOG.md b/CHANGELOG.md
index ee48fc3..93ff067 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,11 @@
 # Changelog
 
+## v0.3.4 — 2026-05-13
+
+### Fixed
+
+- **Include `google/protobuf/duration.proto` in `ContractRegistry.FileDescriptorSet`.** `eventbus.proto` imports `duration.proto` for `StreamConfig.max_age` and `ConsumerConfig.ack_wait`. `protodesc.NewFiles` requires every imported file to be present in the FileDescriptorSet, so the v0.3.3 set (struct + empty + eventbus) silently failed to register any eventbus messages — the engine's contract-types resolver ended up empty, and STRICT_PROTO modules fell through to `protoregistry.GlobalTypes` (which still doesn't contain plugin-local protos). Result: PR 279 image-launch *still* hit `generated codec ... not found` after the v0.3.3 bump. v0.3.4 adds the duration well-known type before the eventbus file in the descriptor set so resolution completes.
+
 ## v0.3.3 — 2026-05-13
 
 ### Fixed
diff --git a/cmd/workflow-plugin-eventbus/plugin.go b/cmd/workflow-plugin-eventbus/plugin.go
index 1f842d3..9e9b6cd 100644
--- a/cmd/workflow-plugin-eventbus/plugin.go
+++ b/cmd/workflow-plugin-eventbus/plugin.go
@@ -7,6 +7,7 @@ import (
 	"google.golang.org/protobuf/reflect/protodesc"
 	"google.golang.org/protobuf/types/descriptorpb"
 	"google.golang.org/protobuf/types/known/anypb"
+	"google.golang.org/protobuf/types/known/durationpb"
 	"google.golang.org/protobuf/types/known/emptypb"
 	"google.golang.org/protobuf/types/known/structpb"
 
@@ -228,6 +229,11 @@ func (p *eventbusPlugin) ContractRegistry() *pb.ContractRegistry {
 			File: []*descriptorpb.FileDescriptorProto{
 				protodesc.ToFileDescriptorProto(structpb.File_google_protobuf_struct_proto),
 				protodesc.ToFileDescriptorProto(emptypb.File_google_protobuf_empty_proto),
+				// eventbus.proto imports google/protobuf/duration.proto for
+				// StreamConfig.max_age + ConsumerConfig.ack_wait — protodesc.NewFiles
+				// requires every imported file to be present in the FileDescriptorSet,
+				// so include the duration well-known type BEFORE eventbus_proto.
+				protodesc.ToFileDescriptorProto(durationpb.File_google_protobuf_duration_proto),
 				protodesc.ToFileDescriptorProto(eventbusv1.File_eventbus_proto),
 			},
 		},
diff --git a/cmd/workflow-plugin-eventbus/plugin_test.go b/cmd/workflow-plugin-eventbus/plugin_test.go
index e5db7bc..68d8ff6 100644
--- a/cmd/workflow-plugin-eventbus/plugin_test.go
+++ b/cmd/workflow-plugin-eventbus/plugin_test.go
@@ -4,10 +4,77 @@ import (
 	"strings"
 	"testing"
 
+	"google.golang.org/protobuf/reflect/protodesc"
+	"google.golang.org/protobuf/reflect/protoreflect"
+	"google.golang.org/protobuf/reflect/protoregistry"
+	"google.golang.org/protobuf/types/dynamicpb"
+
 	eventbus "github.com/GoCodeAlone/workflow-plugin-eventbus"
 	eventbusv1 "github.com/GoCodeAlone/workflow-plugin-eventbus/gen"
 )
 
+// TestContractRegistry_FileDescriptorSetResolvesEveryContractMessage is the
+// regression test for v0.3.3's incomplete FileDescriptorSet (missing
+// google/protobuf/duration.proto which eventbus.proto imports). The engine
+// builds its contract-types resolver via protodesc.NewFiles(registry.
+// FileDescriptorSet). If any imported file is missing, NewFiles silently
+// produces a registry that never registers the eventbus messages, and the
+// engine falls through to protoregistry.GlobalTypes (which does not contain
+// plugin-local protos) at module construction time — failing with
+// "generated codec for protobuf message X not found: proto: not found".
+//
+// This test exercises the exact engine path: read the plugin's
+// ContractRegistry, register the FileDescriptorSet, then assert that every
+// Config/Input/Output/Trigger message named in Contracts can be resolved.
+func TestContractRegistry_FileDescriptorSetResolvesEveryContractMessage(t *testing.T) {
+	p := &eventbusPlugin{}
+	reg := p.ContractRegistry()
+	if reg == nil {
+		t.Fatal("ContractRegistry returned nil")
+	}
+	if reg.FileDescriptorSet == nil || len(reg.FileDescriptorSet.File) == 0 {
+		t.Fatal("ContractRegistry must populate FileDescriptorSet so the engine can resolve plugin-local proto codecs")
+	}
+	files, err := protodesc.NewFiles(reg.FileDescriptorSet)
+	if err != nil {
+		t.Fatalf("protodesc.NewFiles failed — every imported file must be present in FileDescriptorSet: %v", err)
+	}
+	types := new(protoregistry.Types)
+	files.RangeFiles(func(file protoreflect.FileDescriptor) bool {
+		registerMessages(t, types, file.Messages())
+		return true
+	})
+	// Every distinct message name referenced in Contracts (Config/Input/Output)
+	// must be resolvable. This mirrors the workflow engine's
+	// `newMessageByName(messageName, contractTypes)` lookup at
+	// createTypedConfigRequest time.
+	wantNames := map[string]struct{}{}
+	for _, c := range reg.Contracts {
+		for _, name := range []string{c.ConfigMessage, c.InputMessage, c.OutputMessage} {
+			if name == "" {
+				continue
+			}
+			wantNames[name] = struct{}{}
+		}
+	}
+	for name := range wantNames {
+		if _, err := types.FindMessageByName(protoreflect.FullName(name)); err != nil {
+			t.Errorf("FileDescriptorSet missing codec for contract message %q: %v", name, err)
+		}
+	}
+}
+
+func registerMessages(t *testing.T, types *protoregistry.Types, messages protoreflect.MessageDescriptors) {
+	t.Helper()
+	for i := 0; i < messages.Len(); i++ {
+		m := messages.Get(i)
+		if err := types.RegisterMessage(dynamicpb.NewMessageType(m)); err != nil {
+			t.Fatalf("register %q: %v", m.FullName(), err)
+		}
+		registerMessages(t, types, m.Messages())
+	}
+}
+
 // TestCreateTrigger_AliasConsumerToName verifies that BMW-style configs supplying
 // `consumer` instead of the proto-canonical `name` build successfully. This is
 // the core fix shipped in v0.3.1 — without this, BMW pipelines fail with
diff --git a/plugin.json b/plugin.json
index c106974..eef3ca5 100644
--- a/plugin.json
+++ b/plugin.json
@@ -1,6 +1,6 @@
 {
     "name": "workflow-plugin-eventbus",
-    "version": "0.3.3",
+    "version": "0.3.4",
     "description": "Provisions durable event-bus clusters (NATS / Kafka / Kinesis) as IaC and exposes typed pipeline steps for publish / consume operations.",
     "author": "GoCodeAlone",
     "license": "MIT",