diff --git a/unittests/CMakeLists.txt b/unittests/CMakeLists.txt
index 3397d798..1256e8e6 100644
--- a/unittests/CMakeLists.txt
+++ b/unittests/CMakeLists.txt
@@ -1,6 +1,7 @@
 enable_testing()
 
-include(${TF_3RD_PARTY_DIR}/doctest/doctest.cmake)
+find_package(doctest REQUIRED)
+include(doctest)
 
 list(APPEND TF_UNITTESTS 
   utility 
@@ -23,8 +24,7 @@ list(APPEND TF_UNITTESTS
 
 foreach(unittest IN LISTS TF_UNITTESTS)
   add_executable(${unittest} ${unittest}.cpp)
-  target_link_libraries(${unittest} ${PROJECT_NAME} tf::default_settings)
-  target_include_directories(${unittest} PRIVATE ${TF_3RD_PARTY_DIR}/doctest)
+  target_link_libraries(${unittest} ${PROJECT_NAME} tf::default_settings doctest::doctest)
   doctest_discover_tests(${unittest})
 endforeach()
 
diff --git a/unittests/algorithms.cpp b/unittests/algorithms.cpp
index a250713a..09ae9ba5 100644
--- a/unittests/algorithms.cpp
+++ b/unittests/algorithms.cpp
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/taskflow.hpp>
 #include <taskflow/algorithm/reduce.hpp>
 #include <taskflow/algorithm/sort.hpp>
diff --git a/unittests/asyncs.cpp b/unittests/asyncs.cpp
index 28eeaa8c..466687a2 100644
--- a/unittests/asyncs.cpp
+++ b/unittests/asyncs.cpp
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/taskflow.hpp>
 
 // --------------------------------------------------------
diff --git a/unittests/basics.cpp b/unittests/basics.cpp
index f5b9e3dd..e93c3fd3 100644
--- a/unittests/basics.cpp
+++ b/unittests/basics.cpp
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/taskflow.hpp>
 #include <taskflow/algorithm/reduce.hpp>
 
diff --git a/unittests/cancellation.cpp b/unittests/cancellation.cpp
index 3ce1cb8c..6543ee52 100644
--- a/unittests/cancellation.cpp
+++ b/unittests/cancellation.cpp
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/taskflow.hpp>
 
 // EmptyFuture
diff --git a/unittests/compositions.cpp b/unittests/compositions.cpp
index 4fd621b5..e3c91e4c 100644
--- a/unittests/compositions.cpp
+++ b/unittests/compositions.cpp
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/taskflow.hpp>
 
 // --------------------------------------------------------
diff --git a/unittests/control_flow.cpp b/unittests/control_flow.cpp
index 024ace84..11206384 100644
--- a/unittests/control_flow.cpp
+++ b/unittests/control_flow.cpp
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/taskflow.hpp>
 
 // --------------------------------------------------------
diff --git a/unittests/cuda/CMakeLists.txt b/unittests/cuda/CMakeLists.txt
index d0ccc8e9..ccb46721 100644
--- a/unittests/cuda/CMakeLists.txt
+++ b/unittests/cuda/CMakeLists.txt
@@ -13,15 +13,14 @@ list(APPEND TF_CUDA_UNITTESTS
 
 foreach(cudatest IN LISTS TF_CUDA_UNITTESTS)
   add_executable(${cudatest} ${cudatest}.cu)
-  target_link_libraries(${cudatest} ${PROJECT_NAME} tf::default_settings)
-  target_include_directories(${cudatest} PRIVATE ${TF_3RD_PARTY_DIR}/doctest)
-  
+  target_link_libraries(${cudatest} ${PROJECT_NAME} tf::default_settings doctest::doctest)
+
   # avoid cmake 3.18+ warning
   # we let nvcc to decide the flag if the architecture is not given
   if(NOT CUDA_ARCHITECTURES)
     set_property(TARGET ${cudatest} PROPERTY CUDA_ARCHITECTURES OFF)
   endif()
-  
+
   doctest_discover_tests(${cudatest})
 endforeach()
 
diff --git a/unittests/cuda/cuda_algorithms.cu b/unittests/cuda/cuda_algorithms.cu
index cccc04b4..47645273 100644
--- a/unittests/cuda/cuda_algorithms.cu
+++ b/unittests/cuda/cuda_algorithms.cu
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/taskflow.hpp>
 #include <taskflow/cuda/cudaflow.hpp>
 #include <taskflow/cuda/algorithm/for_each.hpp>
diff --git a/unittests/cuda/cuda_basics.cu b/unittests/cuda/cuda_basics.cu
index 8e0fdffd..f97c7822 100644
--- a/unittests/cuda/cuda_basics.cu
+++ b/unittests/cuda/cuda_basics.cu
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/taskflow.hpp>
 #include <taskflow/cuda/cudaflow.hpp>
 
diff --git a/unittests/cuda/cuda_capturer_optimizer.cu b/unittests/cuda/cuda_capturer_optimizer.cu
index 86fcfb72..7cbcf0a5 100644
--- a/unittests/cuda/cuda_capturer_optimizer.cu
+++ b/unittests/cuda/cuda_capturer_optimizer.cu
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/taskflow.hpp>
 #include <taskflow/cuda/cudaflow.hpp>
 #include <taskflow/cuda/algorithm/for_each.hpp>
diff --git a/unittests/cuda/cuda_device.cu b/unittests/cuda/cuda_device.cu
index 49df36aa..fb68b29a 100644
--- a/unittests/cuda/cuda_device.cu
+++ b/unittests/cuda/cuda_device.cu
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/taskflow.hpp>
 #include <taskflow/cuda/cudaflow.hpp>
 
diff --git a/unittests/cuda/cuda_kmeans.cu b/unittests/cuda/cuda_kmeans.cu
index 91495b59..c14d250f 100644
--- a/unittests/cuda/cuda_kmeans.cu
+++ b/unittests/cuda/cuda_kmeans.cu
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/taskflow.hpp>
 #include <taskflow/cuda/cudaflow.hpp>
 #include <taskflow/cuda/algorithm/for_each.hpp>
diff --git a/unittests/cuda/cuda_matrix.cu b/unittests/cuda/cuda_matrix.cu
index 8e9f2421..ec5386f4 100644
--- a/unittests/cuda/cuda_matrix.cu
+++ b/unittests/cuda/cuda_matrix.cu
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/taskflow.hpp>
 #include <taskflow/cuda/cudaflow.hpp>
 
diff --git a/unittests/cuda/cuda_rebinds.cu b/unittests/cuda/cuda_rebinds.cu
index eb9218fa..92798dfd 100644
--- a/unittests/cuda/cuda_rebinds.cu
+++ b/unittests/cuda/cuda_rebinds.cu
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 
 #include <taskflow/taskflow.hpp>
 #include <taskflow/cuda/cudaflow.hpp>
diff --git a/unittests/cuda/cuda_updates.cu b/unittests/cuda/cuda_updates.cu
index bdda539a..d8b52dcf 100644
--- a/unittests/cuda/cuda_updates.cu
+++ b/unittests/cuda/cuda_updates.cu
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 
 #include <taskflow/taskflow.hpp>
 #include <taskflow/cuda/cudaflow.hpp>
diff --git a/unittests/movable.cpp b/unittests/movable.cpp
index 96ce9da3..d5e64b47 100644
--- a/unittests/movable.cpp
+++ b/unittests/movable.cpp
@@ -1,5 +1,5 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/taskflow.hpp>
 
 // increments a counter only on destruction
diff --git a/unittests/pipelines.cpp b/unittests/pipelines.cpp
index 94d8f394..701365c0 100644
--- a/unittests/pipelines.cpp
+++ b/unittests/pipelines.cpp
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 
 #include <taskflow/taskflow.hpp>
 #include <taskflow/algorithm/pipeline.hpp>
diff --git a/unittests/semaphores.cpp b/unittests/semaphores.cpp
index 616191b5..64b8a587 100644
--- a/unittests/semaphores.cpp
+++ b/unittests/semaphores.cpp
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/taskflow.hpp>
 
 // --------------------------------------------------------
diff --git a/unittests/serializer.cpp b/unittests/serializer.cpp
index 92c3ec70..c6a715e6 100644
--- a/unittests/serializer.cpp
+++ b/unittests/serializer.cpp
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/utility/serializer.hpp>
 #include <random>
 
diff --git a/unittests/sorting.cpp b/unittests/sorting.cpp
index 8146324a..ff732fb0 100644
--- a/unittests/sorting.cpp
+++ b/unittests/sorting.cpp
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/taskflow.hpp>
 #include <taskflow/algorithm/sort.hpp>
 
diff --git a/unittests/subflows.cpp b/unittests/subflows.cpp
index 9db430de..e669a2c8 100644
--- a/unittests/subflows.cpp
+++ b/unittests/subflows.cpp
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/taskflow.hpp>
 #include <taskflow/algorithm/reduce.hpp>
 
diff --git a/unittests/sycl/CMakeLists.txt b/unittests/sycl/CMakeLists.txt
index c6481996..3b014d0e 100644
--- a/unittests/sycl/CMakeLists.txt
+++ b/unittests/sycl/CMakeLists.txt
@@ -1,4 +1,4 @@
-list(APPEND TF_SYCL_TESTS 
+list(APPEND TF_SYCL_TESTS
   sycl_basics
   #sycl_algorithms
   #sycl_rebinds
@@ -12,9 +12,8 @@ foreach(sycl_test IN LISTS TF_SYCL_TESTS)
   target_compile_options(${sycl_test} PRIVATE ${TF_SYCL_OPTIONS})
   target_link_options(${sycl_test} PRIVATE ${TF_SYCL_OPTIONS})
   target_link_libraries(${sycl_test}
-    ${PROJECT_NAME} Threads::Threads tf::default_settings
+    ${PROJECT_NAME} Threads::Threads tf::default_settings doctest::doctest
   )
-  target_include_directories(${sycl_test} PRIVATE ${TF_3RD_PARTY_DIR}/doctest)
-  
+
   doctest_discover_tests(${sycl_test})
 endforeach()
diff --git a/unittests/sycl/sycl_algorithms.cpp b/unittests/sycl/sycl_algorithms.cpp
index e029b2ef..7b44ca78 100644
--- a/unittests/sycl/sycl_algorithms.cpp
+++ b/unittests/sycl/sycl_algorithms.cpp
@@ -1,5 +1,5 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/syclflow.hpp>
 
 constexpr float eps = 0.0001f;
diff --git a/unittests/sycl/sycl_basics.cpp b/unittests/sycl/sycl_basics.cpp
index 0ff76969..eac52906 100644
--- a/unittests/sycl/sycl_basics.cpp
+++ b/unittests/sycl/sycl_basics.cpp
@@ -1,5 +1,5 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/sycl/syclflow.hpp>
 
 // task creation
diff --git a/unittests/sycl/sycl_rebinds.cpp b/unittests/sycl/sycl_rebinds.cpp
index 71b2f9de..1b5949fd 100644
--- a/unittests/sycl/sycl_rebinds.cpp
+++ b/unittests/sycl/sycl_rebinds.cpp
@@ -1,5 +1,5 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/syclflow.hpp>
 
 // ----------------------------------------------------------------------------
diff --git a/unittests/traversals.cpp b/unittests/traversals.cpp
index 71aef04b..683915b4 100644
--- a/unittests/traversals.cpp
+++ b/unittests/traversals.cpp
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 
 #include <taskflow/taskflow.hpp>
 
diff --git a/unittests/tsq.cpp b/unittests/tsq.cpp
index 51a137a7..8e9cac56 100644
--- a/unittests/tsq.cpp
+++ b/unittests/tsq.cpp
@@ -49,7 +49,7 @@
 
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 #include <taskflow/taskflow.hpp>
 
 // ============================================================================
diff --git a/unittests/utility.cpp b/unittests/utility.cpp
index 63c49708..01ee81a3 100644
--- a/unittests/utility.cpp
+++ b/unittests/utility.cpp
@@ -1,6 +1,6 @@
 #define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
 
-#include <doctest.h>
+#include <doctest/doctest.h>
 
 #include <taskflow/utility/traits.hpp>
 #include <taskflow/utility/object_pool.hpp>