diff --git a/src/engine/csv-engine-listener.cc b/src/engine/csv-engine-listener.cc
index fb04801..3d0e9d0 100644
--- a/src/engine/csv-engine-listener.cc
+++ b/src/engine/csv-engine-listener.cc
@@ -6,6 +6,10 @@ CsvEngineListener::CsvEngineListener() = default;
 
 CsvEngineListener::~CsvEngineListener() = default;
 
+csv::csv_type const& CsvEngineListener::output() const {
+    return output_;
+}
+
 void CsvEngineListener::on_acknowledgement(User user, UserOrderId id) {
     output_.emplace_back(csv::csv_line_type{
         "A",
diff --git a/src/engine/csv-engine-listener.hh b/src/engine/csv-engine-listener.hh
index 593876b..a33c172 100644
--- a/src/engine/csv-engine-listener.hh
+++ b/src/engine/csv-engine-listener.hh
@@ -13,6 +13,8 @@ struct CsvEngineListener : EngineListener {
 
     virtual ~CsvEngineListener();
 
+    csv::csv_type const& output() const;
+
     /// Called when a new trade or cancel order has been acknowledged.
     void on_acknowledgement(User user, UserOrderId id) override;