diff --git a/examples/plugins/CMakeLists.txt b/examples/plugins/CMakeLists.txt
index 59c2802b45..22bd09775f 100644
--- a/examples/plugins/CMakeLists.txt
+++ b/examples/plugins/CMakeLists.txt
@@ -14,17 +14,21 @@ endif()
 
 project(plugins VERSION 1.0 LANGUAGES CXX)
 
-# NOTE: the next line should be commented out when used outside of the LAMMPS package
-get_filename_component(LAMMPS_SOURCE_DIR ${PROJECT_SOURCE_DIR}/../../src ABSOLUTE)
-set(LAMMPS_HEADER_DIR ${LAMMPS_SOURCE_DIR} CACHE PATH "Location of LAMMPS headers")
-if(NOT LAMMPS_HEADER_DIR)
-  message(FATAL_ERROR "Must set LAMMPS_HEADER_DIR")
-endif()
-
-# by default, install into $HOME/.local (not /usr/local),
-# so that no root access (and sudo) is needed
-if(CMAKE_INSTALL_PREFIX_INITIALIZED_TO_DEFAULT)
-  set(CMAKE_INSTALL_PREFIX "$ENV{HOME}/.local" CACHE PATH "Default install path" FORCE)
+# when this file is included as subdirectory in the LAMMPS build, many settings are directly imported
+if(LAMMPS_DIR)
+  set(LAMMPS_HEADER_DIR ${LAMMPS_SOURCE_DIR})
+else()
+  # NOTE: the next line should be commented out when used outside of the LAMMPS package
+  get_filename_component(LAMMPS_SOURCE_DIR ${PROJECT_SOURCE_DIR}/../../src ABSOLUTE)
+  set(LAMMPS_HEADER_DIR ${LAMMPS_SOURCE_DIR} CACHE PATH "Location of LAMMPS headers")
+  if(NOT LAMMPS_HEADER_DIR)
+    message(FATAL_ERROR "Must set LAMMPS_HEADER_DIR")
+  endif()
+  # by default, install into $HOME/.local (not /usr/local),
+  # so that no root access (and sudo) is needed
+  if(CMAKE_INSTALL_PREFIX_INITIALIZED_TO_DEFAULT)
+    set(CMAKE_INSTALL_PREFIX "$ENV{HOME}/.local" CACHE PATH "Default install path" FORCE)
+  endif()
 endif()
 
 # C++11 is required
@@ -41,9 +45,11 @@ if(CMAKE_SYSTEM_NAME STREQUAL Windows)
   message(FATAL_ERROR "LAMMPS plugins are currently not supported on Windows")
 endif()
 
-set(CMAKE_MODULE_PATH ${CMAKE_SOURCE_DIR})
+set(CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR})
 include(CheckIncludeFileCXX)
-include(LAMMPSInterfaceCXX)
+if(NOT LAMMPS_DIR)
+  include(LAMMPSInterfaceCXX)
+endif()
 
 ##########################
 # building the plugins
@@ -71,3 +77,6 @@ if(CMAKE_SYSTEM_NAME STREQUAL Darwin)
   set_target_properties(morse2plugin nve2plugin helloplugin zero2plugin PROPERTIES
                         LINK_FLAGS "-Wl,-undefined,dynamic_lookup")
 endif()
+
+add_custom_target(plugins ALL ${CMAKE_COMMAND} -E echo "Building Plugins"
+  DEPENDS morse2plugin nve2plugin helloplugin zero2plugin morse2plugin)
diff --git a/unittest/commands/CMakeLists.txt b/unittest/commands/CMakeLists.txt
index 8891647911..b543e7691e 100644
--- a/unittest/commands/CMakeLists.txt
+++ b/unittest/commands/CMakeLists.txt
@@ -1,34 +1,31 @@
 
 # build LAMMPS plugins, but not on Windows
 if((NOT (CMAKE_SYSTEM_NAME STREQUAL "Windows")) AND PKG_PLUGIN)
-  include(ExternalProject)
-  ExternalProject_Add(plugins
-                      SOURCE_DIR      "${LAMMPS_DIR}/examples/plugins"
-                      BINARY_DIR      ${CMAKE_BINARY_DIR}/build-plugins
-                      INSTALL_DIR     ${CMAKE_BINARY_DIR}
-                      CMAKE_ARGS      ${CMAKE_REQUEST_PIC}
-                                      -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}
-                                      -DCMAKE_INSTALL_PREFIX=<INSTALL_DIR>
-                                      -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE}
-                                      -DCMAKE_MAKE_PROGRAM=${CMAKE_MAKE_PROGRAM}
-                                      -DCMAKE_TOOLCHAIN_FILE=${CMAKE_TOOLCHAIN_FILE}
-                     BUILD_BYPRODUCTS <BINARY_DIR>/morse2plugin${CMAKE_SHARED_MODULE_SUFFIX}
-                                      <BINARY_DIR>/nve2plugin${CMAKE_SHARED_MODULE_SUFFIX}
-                                      <BINARY_DIR>/helloplugin${CMAKE_SHARED_MODULE_SUFFIX}
-                     INSTALL_COMMAND ${CMAKE_COMMAND} -E copy_if_different
-                                      <BINARY_DIR>/morse2plugin${CMAKE_SHARED_MODULE_SUFFIX}
-                                      <BINARY_DIR>/nve2plugin${CMAKE_SHARED_MODULE_SUFFIX}
-                                      <BINARY_DIR>/helloplugin${CMAKE_SHARED_MODULE_SUFFIX}
-                                      ${CMAKE_CURRENT_BINARY_DIR}
-                     TEST_COMMAND    "")
+  add_subdirectory(${LAMMPS_DIR}/examples/plugins ${CMAKE_BINARY_DIR}/build-plugins)
 endif()
 
 add_executable(test_simple_commands test_simple_commands.cpp)
+
 if(PKG_PLUGIN)
+  add_custom_target(installplugins
+    ${CMAKE_COMMAND} -E copy_if_different
+    ${CMAKE_BINARY_DIR}/build-plugins/$<CONFIG>/morse2plugin${CMAKE_SHARED_MODULE_SUFFIX}
+    ${CMAKE_BINARY_DIR}/build-plugins/$<CONFIG>/nve2plugin${CMAKE_SHARED_MODULE_SUFFIX}
+    ${CMAKE_BINARY_DIR}/build-plugins/$<CONFIG>/helloplugin${CMAKE_SHARED_MODULE_SUFFIX}
+    ${CMAKE_BINARY_DIR}
+    DEPENDS plugins)
   add_dependencies(test_simple_commands plugins)
+  target_compile_definitions(test_simple_commands PRIVATE LMP_PLUGIN)
 endif()
 target_link_libraries(test_simple_commands PRIVATE lammps gmock)
 add_test(NAME SimpleCommands COMMAND test_simple_commands WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
+if(APPLE)
+  set_tests_properties(SimpleCommands PROPERTIES
+    ENVIRONMENT "DYLD_LIBRARY_PATH=${CMAKE_BINARY_DIR}/build-plugins/$<CONFIG>/:${DYLD_LIBRARY_PATH}")
+else()
+  set_tests_properties(SimpleCommands PROPERTIES
+    ENVIRONMENT "LD_LIBRARY_PATH=${CMAKE_BINARY_DIR}/build-plugins/$<CONFIG>/:${LD_LIBRARY_PATH}")
+endif()
 
 add_executable(test_lattice_region test_lattice_region.cpp)
 target_link_libraries(test_lattice_region PRIVATE lammps gmock)