diff --git a/CHANGELOG.md b/CHANGELOG.md
index bce45103c3..b67841c9cf 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -24,6 +24,7 @@
     - NodeJS:
       - CHANGED: Use node-api instead of NAN. [#6452](/~https://github.com/Project-OSRM/osrm-backend/pull/6452)
     - Misc:
+      - CHANGED: Use thread_local instead of boost::thread_specific_ptr. [#6991](/~https://github.com/Project-OSRM/osrm-backend/pull/6991)
       - CHANGED: Bump flatbuffers to v24.3.25 version. [#6988](/~https://github.com/Project-OSRM/osrm-backend/pull/6988)
       - CHANGED: Add .reserve(...) to assembleGeometry function. [#6983](/~https://github.com/Project-OSRM/osrm-backend/pull/6983)
       - CHANGED: Get rid of boost::optional leftovers. [#6977](/~https://github.com/Project-OSRM/osrm-backend/pull/6977)
diff --git a/include/engine/search_engine_data.hpp b/include/engine/search_engine_data.hpp
index 16ffa25b13..30d8e7c192 100644
--- a/include/engine/search_engine_data.hpp
+++ b/include/engine/search_engine_data.hpp
@@ -5,8 +5,6 @@
 #include "util/query_heap.hpp"
 #include "util/typedefs.hpp"
 
-#include <boost/thread/tss.hpp>
-
 namespace osrm::engine
 {
 
@@ -45,19 +43,19 @@ template <> struct SearchEngineData<routing_algorithms::ch::Algorithm>
                                                 ManyToManyHeapData,
                                                 util::UnorderedMapStorage<NodeID, int>>;
 
-    using SearchEngineHeapPtr = boost::thread_specific_ptr<QueryHeap>;
+    using SearchEngineHeapPtr = std::unique_ptr<QueryHeap>;
 
-    using ManyToManyHeapPtr = boost::thread_specific_ptr<ManyToManyQueryHeap>;
+    using ManyToManyHeapPtr = std::unique_ptr<ManyToManyQueryHeap>;
 
-    static SearchEngineHeapPtr forward_heap_1;
-    static SearchEngineHeapPtr reverse_heap_1;
-    static SearchEngineHeapPtr forward_heap_2;
-    static SearchEngineHeapPtr reverse_heap_2;
-    static SearchEngineHeapPtr forward_heap_3;
-    static SearchEngineHeapPtr reverse_heap_3;
-    static ManyToManyHeapPtr many_to_many_heap;
-    static SearchEngineHeapPtr map_matching_forward_heap_1;
-    static SearchEngineHeapPtr map_matching_reverse_heap_1;
+    static thread_local SearchEngineHeapPtr forward_heap_1;
+    static thread_local SearchEngineHeapPtr reverse_heap_1;
+    static thread_local SearchEngineHeapPtr forward_heap_2;
+    static thread_local SearchEngineHeapPtr reverse_heap_2;
+    static thread_local SearchEngineHeapPtr forward_heap_3;
+    static thread_local SearchEngineHeapPtr reverse_heap_3;
+    static thread_local ManyToManyHeapPtr many_to_many_heap;
+    static thread_local SearchEngineHeapPtr map_matching_forward_heap_1;
+    static thread_local SearchEngineHeapPtr map_matching_reverse_heap_1;
 
     void InitializeOrClearMapMatchingThreadLocalStorage(unsigned number_of_nodes);
 
@@ -127,16 +125,16 @@ template <> struct SearchEngineData<routing_algorithms::mld::Algorithm>
                                                  MapMatchingMultiLayerDijkstraHeapData,
                                                  util::TwoLevelStorage<NodeID, int>>;
 
-    using SearchEngineHeapPtr = boost::thread_specific_ptr<QueryHeap>;
-    using ManyToManyHeapPtr = boost::thread_specific_ptr<ManyToManyQueryHeap>;
-    using MapMatchingHeapPtr = boost::thread_specific_ptr<MapMatchingQueryHeap>;
+    using SearchEngineHeapPtr = std::unique_ptr<QueryHeap>;
+    using ManyToManyHeapPtr = std::unique_ptr<ManyToManyQueryHeap>;
+    using MapMatchingHeapPtr = std::unique_ptr<MapMatchingQueryHeap>;
 
-    static SearchEngineHeapPtr forward_heap_1;
-    static SearchEngineHeapPtr reverse_heap_1;
-    static MapMatchingHeapPtr map_matching_forward_heap_1;
-    static MapMatchingHeapPtr map_matching_reverse_heap_1;
+    static thread_local SearchEngineHeapPtr forward_heap_1;
+    static thread_local SearchEngineHeapPtr reverse_heap_1;
+    static thread_local MapMatchingHeapPtr map_matching_forward_heap_1;
+    static thread_local MapMatchingHeapPtr map_matching_reverse_heap_1;
 
-    static ManyToManyHeapPtr many_to_many_heap;
+    static thread_local ManyToManyHeapPtr many_to_many_heap;
 
     void InitializeOrClearFirstThreadLocalStorage(unsigned number_of_nodes,
                                                   unsigned number_of_boundary_nodes);
@@ -148,4 +146,4 @@ template <> struct SearchEngineData<routing_algorithms::mld::Algorithm>
 };
 } // namespace osrm::engine
 
-#endif // SEARCH_ENGINE_DATA_HPP
+#endif // SEARCH_ENGINE_DATA_HPP
\ No newline at end of file
diff --git a/src/engine/search_engine_data.cpp b/src/engine/search_engine_data.cpp
index dd1a053e0e..e749db6c46 100644
--- a/src/engine/search_engine_data.cpp
+++ b/src/engine/search_engine_data.cpp
@@ -5,16 +5,18 @@ namespace osrm::engine
 
 // CH heaps
 using CH = routing_algorithms::ch::Algorithm;
-SearchEngineData<CH>::SearchEngineHeapPtr SearchEngineData<CH>::forward_heap_1;
-SearchEngineData<CH>::SearchEngineHeapPtr SearchEngineData<CH>::reverse_heap_1;
-SearchEngineData<CH>::SearchEngineHeapPtr SearchEngineData<CH>::forward_heap_2;
-SearchEngineData<CH>::SearchEngineHeapPtr SearchEngineData<CH>::reverse_heap_2;
-SearchEngineData<CH>::SearchEngineHeapPtr SearchEngineData<CH>::forward_heap_3;
-SearchEngineData<CH>::SearchEngineHeapPtr SearchEngineData<CH>::reverse_heap_3;
-SearchEngineData<CH>::SearchEngineHeapPtr SearchEngineData<CH>::map_matching_forward_heap_1;
-SearchEngineData<CH>::SearchEngineHeapPtr SearchEngineData<CH>::map_matching_reverse_heap_1;
-
-SearchEngineData<CH>::ManyToManyHeapPtr SearchEngineData<CH>::many_to_many_heap;
+thread_local SearchEngineData<CH>::SearchEngineHeapPtr SearchEngineData<CH>::forward_heap_1;
+thread_local SearchEngineData<CH>::SearchEngineHeapPtr SearchEngineData<CH>::reverse_heap_1;
+thread_local SearchEngineData<CH>::SearchEngineHeapPtr SearchEngineData<CH>::forward_heap_2;
+thread_local SearchEngineData<CH>::SearchEngineHeapPtr SearchEngineData<CH>::reverse_heap_2;
+thread_local SearchEngineData<CH>::SearchEngineHeapPtr SearchEngineData<CH>::forward_heap_3;
+thread_local SearchEngineData<CH>::SearchEngineHeapPtr SearchEngineData<CH>::reverse_heap_3;
+thread_local SearchEngineData<CH>::SearchEngineHeapPtr
+    SearchEngineData<CH>::map_matching_forward_heap_1;
+thread_local SearchEngineData<CH>::SearchEngineHeapPtr
+    SearchEngineData<CH>::map_matching_reverse_heap_1;
+
+thread_local SearchEngineData<CH>::ManyToManyHeapPtr SearchEngineData<CH>::many_to_many_heap;
 
 void SearchEngineData<CH>::InitializeOrClearMapMatchingThreadLocalStorage(unsigned number_of_nodes)
 {
@@ -114,11 +116,13 @@ void SearchEngineData<CH>::InitializeOrClearManyToManyThreadLocalStorage(unsigne
 
 // MLD
 using MLD = routing_algorithms::mld::Algorithm;
-SearchEngineData<MLD>::SearchEngineHeapPtr SearchEngineData<MLD>::forward_heap_1;
-SearchEngineData<MLD>::SearchEngineHeapPtr SearchEngineData<MLD>::reverse_heap_1;
-SearchEngineData<MLD>::MapMatchingHeapPtr SearchEngineData<MLD>::map_matching_forward_heap_1;
-SearchEngineData<MLD>::MapMatchingHeapPtr SearchEngineData<MLD>::map_matching_reverse_heap_1;
-SearchEngineData<MLD>::ManyToManyHeapPtr SearchEngineData<MLD>::many_to_many_heap;
+thread_local SearchEngineData<MLD>::SearchEngineHeapPtr SearchEngineData<MLD>::forward_heap_1;
+thread_local SearchEngineData<MLD>::SearchEngineHeapPtr SearchEngineData<MLD>::reverse_heap_1;
+thread_local SearchEngineData<MLD>::MapMatchingHeapPtr
+    SearchEngineData<MLD>::map_matching_forward_heap_1;
+thread_local SearchEngineData<MLD>::MapMatchingHeapPtr
+    SearchEngineData<MLD>::map_matching_reverse_heap_1;
+thread_local SearchEngineData<MLD>::ManyToManyHeapPtr SearchEngineData<MLD>::many_to_many_heap;
 
 void SearchEngineData<MLD>::InitializeOrClearMapMatchingThreadLocalStorage(
     unsigned number_of_nodes, unsigned number_of_boundary_nodes)
@@ -178,4 +182,4 @@ void SearchEngineData<MLD>::InitializeOrClearManyToManyThreadLocalStorage(
         many_to_many_heap.reset(new ManyToManyQueryHeap(number_of_nodes, number_of_boundary_nodes));
     }
 }
-} // namespace osrm::engine
+} // namespace osrm::engine
\ No newline at end of file