diff --git a/native_backends.go b/native_backends.go
index 16a0bf3..e1d88d1 100644
--- a/native_backends.go
+++ b/native_backends.go
@@ -50,6 +50,7 @@ func RecordActivity(_, _, _, _ string, _ any) {}
 
 // ptrOf and hostError are used by wasm_backends.go (wasip1 only); provide
 // stubs here so the non-WASM build does not need them.
+//
 //nolint:unused // used in wasm_backends.go in WASM builds
 type hostError struct{ msg string }
 
diff --git a/wasm_backends.go b/wasm_backends.go
index 8e6e2eb..7fc01e3 100644
--- a/wasm_backends.go
+++ b/wasm_backends.go
@@ -185,7 +185,7 @@ func EmitEvent(topic string, payload any) {
 type activityInput struct {
 	TaskID       string `json:"task_id"`
 	ProjectID    string `json:"project_id"`
-	ActorID      string `json:"actor_id"`
+	ActorID      string `json:"actor_id,omitempty"`
 	ActivityType string `json:"activity_type"`
 	Content      any    `json:"content"`
 }
@@ -202,13 +202,8 @@ func RecordActivity(taskID, projectID, actorUserID, activityType string, content
 		ActivityType: activityType,
 		Content:      content,
 	}
-	payloadBytes, err := json.Marshal(inp)
-	if err != nil {
-		return
-	}
-	if !hostActivityRecord(int64(ptrOf(payloadBytes)), int64(len(payloadBytes))) {
-		return
-	}
+	payloadBytes, _ := json.Marshal(inp)
+	hostActivityRecord(int64(ptrOf(payloadBytes)), int64(len(payloadBytes)))
 }
 
 // ── Helpers ───────────────────────────────────────────────────────────────────