diff --git a/src/musikcore/library/LocalMetadataProxy.cpp b/src/musikcore/library/LocalMetadataProxy.cpp
index bd2b90bb8..06ed54fb9 100644
--- a/src/musikcore/library/LocalMetadataProxy.cpp
+++ b/src/musikcore/library/LocalMetadataProxy.cpp
@@ -124,6 +124,10 @@ class ExternalIdListToTrackListQuery : public TrackListQueryBase {
             return Headers();
         }
 
+        Durations GetDurations() noexcept override {
+            return Durations();
+        }
+
         size_t GetQueryHash() noexcept override {
             return 0;
         }
diff --git a/src/musikcore/library/query/CategoryTrackListQuery.h b/src/musikcore/library/query/CategoryTrackListQuery.h
index 8012444c2..6158393c1 100755
--- a/src/musikcore/library/query/CategoryTrackListQuery.h
+++ b/src/musikcore/library/query/CategoryTrackListQuery.h
@@ -82,6 +82,9 @@ namespace musik { namespace core { namespace library { namespace query {
             Result GetResult() noexcept override;
             Headers GetHeaders() noexcept override;
             size_t GetQueryHash() noexcept override;
+            Durations GetDurations() noexcept override { 
+                return std::make_shared<std::map<size_t, size_t>>();
+            }
 
             /* ISerializableQuery */
             std::string SerializeQuery() override;
diff --git a/src/musikcore/library/query/DirectoryTrackListQuery.h b/src/musikcore/library/query/DirectoryTrackListQuery.h
index 632eb9c47..b13a24383 100644
--- a/src/musikcore/library/query/DirectoryTrackListQuery.h
+++ b/src/musikcore/library/query/DirectoryTrackListQuery.h
@@ -57,7 +57,10 @@ namespace musik { namespace core { namespace library { namespace query {
             Result GetResult() noexcept override { return this->result; }
             Headers GetHeaders() noexcept override { return this->headers; }
             size_t GetQueryHash() noexcept override { return this->hash; }
-
+            Durations GetDurations() noexcept override { 
+                return std::make_shared<std::map<size_t, size_t>>();
+            }
+        
             /* ISerializableQuery */
             std::string SerializeQuery() override;
             std::string SerializeResult() override;
diff --git a/src/musikcore/library/query/GetPlaylistQuery.h b/src/musikcore/library/query/GetPlaylistQuery.h
index dddd3af7c..a3efdaa2b 100644
--- a/src/musikcore/library/query/GetPlaylistQuery.h
+++ b/src/musikcore/library/query/GetPlaylistQuery.h
@@ -59,6 +59,9 @@ namespace musik { namespace core { namespace library { namespace query {
             Result GetResult() noexcept override;
             Headers GetHeaders() noexcept override;
             size_t GetQueryHash() noexcept override;
+            Durations GetDurations() noexcept override { 
+                return std::make_shared<std::map<size_t, size_t>>();
+            }
 
             /* ISerializableQuery */
             std::string SerializeQuery() override;
diff --git a/src/musikcore/library/query/NowPlayingTrackListQuery.h b/src/musikcore/library/query/NowPlayingTrackListQuery.h
index 183842069..a75ba74b1 100755
--- a/src/musikcore/library/query/NowPlayingTrackListQuery.h
+++ b/src/musikcore/library/query/NowPlayingTrackListQuery.h
@@ -58,6 +58,9 @@ namespace musik { namespace core { namespace library { namespace query {
             Result GetResult() noexcept override;
             Headers GetHeaders() noexcept override;
             size_t GetQueryHash() noexcept override;
+            Durations GetDurations() noexcept override { 
+                return std::make_shared<std::map<size_t, size_t>>();
+            }
 
         protected:
             /* QueryBase */
diff --git a/src/musikcore/library/query/SearchTrackListQuery.h b/src/musikcore/library/query/SearchTrackListQuery.h
index a3d21975f..a8c2730e5 100755
--- a/src/musikcore/library/query/SearchTrackListQuery.h
+++ b/src/musikcore/library/query/SearchTrackListQuery.h
@@ -60,6 +60,9 @@ namespace musik { namespace core { namespace library { namespace query {
             Result GetResult() noexcept override;
             Headers GetHeaders() noexcept override;
             size_t GetQueryHash() noexcept override;
+            Durations GetDurations() noexcept override { 
+                return std::make_shared<std::map<size_t, size_t>>();
+            }
 
             /* ISerializableQuery */
             std::string SerializeQuery() override;
diff --git a/src/musikcore/library/query/TrackListQueryBase.h b/src/musikcore/library/query/TrackListQueryBase.h
index d372db7ce..b0669d375 100755
--- a/src/musikcore/library/query/TrackListQueryBase.h
+++ b/src/musikcore/library/query/TrackListQueryBase.h
@@ -49,7 +49,8 @@ namespace musik { namespace core { namespace library { namespace query {
     class TrackListQueryBase : public musik::core::library::query::QueryBase {
         public:
             typedef std::shared_ptr<musik::core::TrackList> Result;
-            typedef std::shared_ptr<std::set<size_t> > Headers;
+            typedef std::shared_ptr<std::set<size_t>> Headers;
+            typedef std::shared_ptr<std::map<size_t, size_t>> Durations;
 
             DELETE_COPY_AND_ASSIGNMENT_DEFAULTS(TrackListQueryBase)
 
@@ -61,6 +62,7 @@ namespace musik { namespace core { namespace library { namespace query {
             /* virtual methods we define */
             virtual Result GetResult() = 0;
             virtual Headers GetHeaders() = 0;
+            virtual Durations GetDurations() = 0;
             virtual size_t GetQueryHash() = 0;
 
             virtual void SetLimitAndOffset(int limit, int offset = 0) noexcept {