diff --git a/CMakeLists.txt b/CMakeLists.txt
index c6e1c8bc..17d73eb3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -3,25 +3,11 @@
 cmake_minimum_required(VERSION 3.10)
 
 project(callback VERSION 0.1)
-enable_language(CXX)
 
-# common XO cmake macros (see proj/xo-cmake)
+include(GNUInstallDirs)
 include(cmake/xo-bootstrap-macros.cmake)
 
-# ----------------------------------------------------------------
-# unit test setup (for consistency with other xo libraries.  no unit tests as of 10oct2023)
-
-enable_testing()
-# activate code coverage for all executables + libraries (when configured with -DCODE_COVERAGE=ON)
-add_code_coverage()
-# 1. assuming that /nix/store/ prefixes .hpp files belonging to gcc, catch2 etc.
-#    we're not interested in code coverage for these sources.
-# 2. exclude the utest/ subdir, we don't need coverage on the unit tests themselves;
-#    rather,  want coverage on the code that the unit tests exercise.
-#
-# NOTE: this seems to work only with the 'ccov-all' target.  In particular,  doesn't seem to do anything with the 'ccov' target
-#
-add_code_coverage_all_targets(EXCLUDE /nix/store/* ${PROJECT_SOURCE_DIR}/utest/* ${PROJECT_BINARY_DIR}/local/* ${PROJECT_SOURCE_DIR}/repo/*)
+xo_cxx_toplevel_options3()
 
 # ----------------------------------------------------------------
 # common c++ settings
@@ -31,8 +17,6 @@ set(PROJECT_CXX_FLAGS "")
 #set(PROJECT_CXX_FLAGS "-fconcepts-diagnostics-depth=2")
 add_definitions(${PROJECT_CXX_FLAGS})
 
-xo_toplevel_compile_options()
-
 # ----------------------------------------------------------------
 # sources
 
@@ -40,7 +24,7 @@ add_subdirectory(src/callback)
 #add_subdirectory(utest)
 
 # ----------------------------------------------------------------
-# provide find_package() support to customers
+# provide find_package() support
 
 xo_export_cmake_config(${PROJECT_NAME} ${PROJECT_VERSION} ${PROJECT_NAME}Targets)