diff --git a/tree/CMakeLists.txt b/tree/CMakeLists.txt
index 8f9946c..b9d6e9b 100644
--- a/tree/CMakeLists.txt
+++ b/tree/CMakeLists.txt
@@ -50,70 +50,80 @@ if(APPLE)
   set (CMAKE_FIND_FRAMEWORK LAST)
 endif()
 
-# Fetch pybind to be able to use pybind11_add_module symbol.
-set(PYBIND_VER v2.6.2)
-include(FetchContent)
-FetchContent_Declare(
-  pybind11
-  GIT_REPOSITORY https://github.com/pybind/pybind11
-  GIT_TAG        ${PYBIND_VER}
-)
-if(NOT pybind11_POPULATED)
-    FetchContent_Populate(pybind11)
-    add_subdirectory(${pybind11_SOURCE_DIR} ${pybind11_BINARY_DIR})
-    include_directories(${pybind11_INCLUDE_DIR})
-endif()
-
-# Needed to disable Abseil tests.
-set (BUILD_TESTING OFF)
-
-# Include abseil-cpp.
-set(ABSEIL_VER 20210324.2)
-include(ExternalProject)
-set(ABSEIL_CMAKE_ARGS
-    "-DCMAKE_INSTALL_PREFIX=${CMAKE_SOURCE_DIR}/abseil-cpp"
-    "-DCMAKE_CXX_STANDARD=${CMAKE_CXX_STANDARD}"
-    "-DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}"
-    "-DCMAKE_CXX_FLAGS=${CMAKE_CXX_FLAGS}"
-    "-DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE}"
-    "-DCMAKE_POSITION_INDEPENDENT_CODE=${CMAKE_POSITION_INDEPENDENT_CODE}"
-    "-DLIBRARY_OUTPUT_PATH=${CMAKE_SOURCE_DIR}/abseil-cpp/lib")
-if(DEFINED CMAKE_OSX_ARCHITECTURES)
-    set(ABSEIL_CMAKE_ARGS
-        ${ABSEIL_CMAKE_ARGS}
-        "-DCMAKE_OSX_ARCHITECTURES=${CMAKE_OSX_ARCHITECTURES}")
+find_package(pybind11 CONFIG)
+
+if (NOT pybind11_FOUND)
+  # Fetch pybind to be able to use pybind11_add_module symbol.
+  set(PYBIND_VER v2.6.2)
+  include(FetchContent)
+  FetchContent_Declare(
+    pybind11
+    GIT_REPOSITORY https://github.com/pybind/pybind11
+    GIT_TAG        ${PYBIND_VER}
+  )
+  if(NOT pybind11_POPULATED)
+      FetchContent_Populate(pybind11)
+      add_subdirectory(${pybind11_SOURCE_DIR} ${pybind11_BINARY_DIR})
+      include_directories(${pybind11_INCLUDE_DIR})
+  endif()
 endif()
-ExternalProject_Add(abseil-cpp
-  GIT_REPOSITORY    https://github.com/abseil/abseil-cpp.git
-  GIT_TAG           ${ABSEIL_VER}
-  PREFIX            ${CMAKE_SOURCE_DIR}/abseil-cpp
-  CMAKE_ARGS        ${ABSEIL_CMAKE_ARGS}
-)
-ExternalProject_Get_Property(abseil-cpp install_dir)
-set(abseil_install_dir ${install_dir})
-include_directories (${abseil_install_dir}/include)
-
 
 # Define pybind11 tree module.
 pybind11_add_module(_tree tree.h tree.cc)
-add_dependencies(_tree abseil-cpp)
 
-if (WIN32 OR MSVC)
-    set(ABSEIL_LIB_PREF "absl")
-    set(LIB_SUFF "lib")
+find_package(absl)
+
+if (NOT absl_FOUND)
+  # Needed to disable Abseil tests.
+  set (BUILD_TESTING OFF)
+
+  # Include abseil-cpp.
+  set(ABSEIL_VER 20210324.2)
+  include(ExternalProject)
+  set(ABSEIL_CMAKE_ARGS
+      "-DCMAKE_INSTALL_PREFIX=${CMAKE_SOURCE_DIR}/abseil-cpp"
+      "-DCMAKE_CXX_STANDARD=${CMAKE_CXX_STANDARD}"
+      "-DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}"
+      "-DCMAKE_CXX_FLAGS=${CMAKE_CXX_FLAGS}"
+      "-DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE}"
+      "-DCMAKE_POSITION_INDEPENDENT_CODE=${CMAKE_POSITION_INDEPENDENT_CODE}"
+      "-DLIBRARY_OUTPUT_PATH=${CMAKE_SOURCE_DIR}/abseil-cpp/lib")
+  if(DEFINED CMAKE_OSX_ARCHITECTURES)
+      set(ABSEIL_CMAKE_ARGS
+          ${ABSEIL_CMAKE_ARGS}
+          "-DCMAKE_OSX_ARCHITECTURES=${CMAKE_OSX_ARCHITECTURES}")
+  endif()
+  ExternalProject_Add(abseil-cpp
+    GIT_REPOSITORY    https://github.com/abseil/abseil-cpp.git
+    GIT_TAG           ${ABSEIL_VER}
+    PREFIX            ${CMAKE_SOURCE_DIR}/abseil-cpp
+    CMAKE_ARGS        ${ABSEIL_CMAKE_ARGS}
+  )
+  ExternalProject_Get_Property(abseil-cpp install_dir)
+  set(abseil_install_dir ${install_dir})
+  include_directories (${abseil_install_dir}/include)
+
+  add_dependencies(_tree abseil-cpp)
+
+  if (WIN32 OR MSVC)
+      set(ABSEIL_LIB_PREF "absl")
+      set(LIB_SUFF "lib")
+  else()
+      set(ABSEIL_LIB_PREF "libabsl")
+      set(LIB_SUFF "a")
+  endif()
+
+  # Link abseil static libs.
+  # We don't use find_library here to force cmake to build abseil before linking.
+  set(ABSEIL_LIBS int128 raw_hash_set raw_logging_internal strings throw_delegate)
+  foreach(ABSEIL_LIB IN LISTS ABSEIL_LIBS)
+    target_link_libraries(_tree PRIVATE
+        "${abseil_install_dir}/lib/${ABSEIL_LIB_PREF}_${ABSEIL_LIB}.${LIB_SUFF}")
+  endforeach()
 else()
-    set(ABSEIL_LIB_PREF "libabsl")
-    set(LIB_SUFF "a")
+  target_link_libraries(_tree PRIVATE absl::int128 absl::raw_hash_set absl::raw_logging_internal absl::strings absl::throw_delegate)
 endif()
 
-# Link abseil static libs.
-# We don't use find_library here to force cmake to build abseil before linking.
-set(ABSEIL_LIBS int128 raw_hash_set raw_logging_internal strings throw_delegate)
-foreach(ABSEIL_LIB IN LISTS ABSEIL_LIBS)
-  target_link_libraries(_tree PRIVATE
-      "${abseil_install_dir}/lib/${ABSEIL_LIB_PREF}_${ABSEIL_LIB}.${LIB_SUFF}")
-endforeach()
-
 # Make the module private to tree package.
 set_target_properties(_tree PROPERTIES OUTPUT_NAME tree/_tree)