diff --git a/CMakeLists.txt b/CMakeLists.txt
index 03891ace..bb43a0d1 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -10,7 +10,7 @@ cmake_minimum_required(VERSION 3.5.0 FATAL_ERROR)
 
 #-----------------------------------------------------------------------------
 
-project(protozero VERSION 1.7.0 LANGUAGES CXX)
+project(protozero VERSION 1.7.0 LANGUAGES CXX C)
 
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)