diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index bcf3d28..9c116df 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -1,8 +1,5 @@
 cmake_minimum_required(VERSION 4.2 FATAL_ERROR)
 
-# workaround clang bug
-set(CMAKE_CXX_STDLIB_MODULES_JSON "/usr/lib/llvm-21/lib/libc++.modules.json")
-
 set(CMAKE_EXPERIMENTAL_CXX_IMPORT_STD "d0edc3af-4c50-42ea-a356-e2862fe7a444")
 set(CMAKE_CXX_MODULE_STD ON)
 set(CMAKE_CXX_STANDARD 26)
diff --git a/test/CMakePresets.json b/test/CMakePresets.json
index 7c18531..a7b6942 100644
--- a/test/CMakePresets.json
+++ b/test/CMakePresets.json
@@ -11,6 +11,7 @@
             "generator": "Ninja",
             "binaryDir": "${sourceDir}/build/${presetName}",
             "cacheVariables": {
+                "CMAKE_CXX_STDLIB_MODULES_JSON": "/usr/lib/llvm-21/lib/libc++.modules.json",
                 "CMAKE_CXX_COMPILER": "/usr/bin/clang++",
                 "CMAKE_CXX_FLAGS": "-stdlib=libc++",
                 "CMAKE_BUILD_TYPE": "Debug"