diff --git a/src/electromagnet/CMakeLists.txt b/src/electromagnet/CMakeLists.txt
index 5dcebbbb..5259792a 100644
--- a/src/electromagnet/CMakeLists.txt
+++ b/src/electromagnet/CMakeLists.txt
@@ -2,4 +2,5 @@ upm_mixed_module_init (NAME electromagnet
     DESCRIPTION "Electromagnet"
     CPP_HDR electromagnet.hpp
     CPP_SRC electromagnet.cxx
+    IFACE_HDR iElectromagnet.hpp
     REQUIRES mraa)
diff --git a/src/groveelectromagnet/CMakeLists.txt b/src/groveelectromagnet/CMakeLists.txt
index 5353b63b..0757c785 100644
--- a/src/groveelectromagnet/CMakeLists.txt
+++ b/src/groveelectromagnet/CMakeLists.txt
@@ -2,4 +2,5 @@ set (libname "groveelectromagnet")
 set (libdescription "Electromagnet")
 set (module_src ${libname}.cxx)
 set (module_hpp ${libname}.hpp)
+set (module_iface iElectromagnet.hpp)
 upm_module_init(mraa)