diff --git a/5.patch b/5.patch
new file mode 100644
index 0000000..f9424a1
--- /dev/null
+++ b/5.patch
@@ -0,0 +1,27 @@
+From 860fe53a085477365b46f31d46108d630f6c8aa1 Mon Sep 17 00:00:00 2001
+From: "Benjamin A. Beasley" <code@musicinmybrain.net>
+Date: Tue, 14 Apr 2026 20:29:17 +0100
+Subject: [PATCH] Update minimum CMake version to 3.12
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+CMake 4.0 drops support for CMake <3.5, so minimum versions need to be
+adjusted for forward compatibility. We might as well ask for CMake 3.12,
+which can be considered the oldest “modern” CMake release, which is
+available in all known supported Linux distributions today, and which is
+likely to remain supported for some time.
+---
+ CMakeLists.txt | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/CMakeLists.txt b/CMakeLists.txt
+index ea6f90c..b03f9f4 100644
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -1,4 +1,4 @@
+-cmake_minimum_required(VERSION 3.2)
++cmake_minimum_required(VERSION 3.12)
+ project (xxhashct)
+ 
+ set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
diff --git a/xxhashct.spec b/xxhashct.spec
index aaefd7f..2f40cc1 100644
--- a/xxhashct.spec
+++ b/xxhashct.spec
@@ -11,8 +11,14 @@ License:        MIT
 URL:            https://github.com/ekpyron/xxhashct
 Source:         %{url}/archive/%{commit}/xxhashct-%{commit}.tar.gz
 
+# Update minimum CMake version to 3.12
+# https://github.com/ekpyron/xxhashct/pull/5
+# Fixes compatibility with CMake 4.
+Patch:          %{url}/pull/5.patch
+
+BuildSystem:    cmake
+
 BuildRequires:  gcc-c++
-BuildRequires:  cmake
 # For tests:
 BuildRequires:  xxhash-devel
 
@@ -41,21 +47,10 @@ The xxhashct-devel package contains libraries and header files for developing
 applications that use xxhashct.
 
 
-%prep
-%autosetup -n xxhashct-%{commit} -p1
-
-
-%conf
-%cmake
-
-
-%build
-%cmake_build
-
-
 %install
 # The upstream CMake build system only builds tests.
-install -D -p -m 0644 -t '%{buildroot}%{_includedir}' xxh32.hpp xxh64.hpp
+install -D --preserve-timestamps --mode=0644 \
+    --target='%{buildroot}%{_includedir}' xxh32.hpp xxh64.hpp
 
 
 %check