diff --git a/test/x4/CMakeLists.txt b/test/x4/CMakeLists.txt
index 47821e52d..9ef0da995 100644
--- a/test/x4/CMakeLists.txt
+++ b/test/x4/CMakeLists.txt
@@ -4,6 +4,11 @@
 # Distributed under the Boost Software License, Version 1.0.
 # https://www.boost.org/LICENSE_1_0.txt
 
+add_library(x4_test_pch OBJECT pch.cpp)
+set_target_properties(x4_test_pch PROPERTIES CXX_EXTENSIONS OFF)
+target_link_libraries(x4_test_pch PRIVATE Iris::X4 iris_cxx_test)
+target_precompile_headers(x4_test_pch PUBLIC pch.hpp)
+
 function(x4_define_test_headers test_name)
     iris_define_test_headers(x4_${test_name} PRIVATE FILE_SET HEADERS FILES ${ARGN})
 endfunction()
@@ -11,6 +16,7 @@ endfunction()
 function(x4_define_test test_name)
     iris_define_test(x4_${test_name} ${ARGN})
     iris_define_test_headers(x4_${test_name} iris_x4_test.hpp)
+    target_precompile_headers(x4_${test_name}_test REUSE_FROM x4_test_pch)
     target_link_libraries(x4_${test_name}_test PRIVATE Iris::X4)
     set_target_properties(x4_${test_name}_test PROPERTIES FOLDER "test/x4")
 
diff --git a/test/x4/pch.cpp b/test/x4/pch.cpp
new file mode 100644
index 000000000..e69de29bb
diff --git a/test/x4/pch.hpp b/test/x4/pch.hpp
new file mode 100644
index 000000000..20c4fba06
--- /dev/null
+++ b/test/x4/pch.hpp
@@ -0,0 +1,23 @@
+#ifndef IRIS_X4_TEST_PCH_HPP
+#define IRIS_X4_TEST_PCH_HPP
+
+#include <iris/alloy/tuple.hpp>
+#include <iris/alloy/adapt.hpp>
+
+#include <iris/rvariant.hpp>
+#include <iris/rvariant/rvariant_io.hpp>
+
+#include <algorithm>
+#include <concepts>
+#include <iostream>
+#include <iterator>
+#include <memory>
+#include <optional>
+#include <ranges>
+#include <string>
+#include <string_view>
+#include <type_traits>
+#include <utility>
+#include <vector>
+
+#endif