diff --git a/cmake/modules/CMakeBuiltinFunctionsDocumentation.cmake b/cmake/modules/CMakeBuiltinFunctionsDocumentation.cmake
new file mode 100644
index 0000000000000000000000000000000000000000..1231eed6a4695a4aaeffc600c48da320aec79142
--- /dev/null
+++ b/cmake/modules/CMakeBuiltinFunctionsDocumentation.cmake
@@ -0,0 +1,94 @@
+# This modules contains only documentation for CMake builtins.
+# This is necessary to have an complete API documentation.
+#
+# .. cmake_function:: add_subdirectory
+#
+#    .. cmake_param:: dir
+#       :single:
+#       :positional:
+#       :required:
+#
+#       The :code:`CMakeLists.txt` file from this subdirectory
+#       will be executed next.
+#
+#    .. cmake_param:: EXCLUDE_FROM_ALL
+#       :option:
+#
+#       Whether targets added in this subdirectory should be built
+#       during :code:`make all`.
+#
+#    This is a cmake builtin command.
+#    For detailed information, check the cmake documentation:
+#
+#    .. code-block: bash
+#
+#       cmake --help-command add_subdirectory
+#
+# .. cmake_function:: install
+#
+#    Define installation rules to customize the behaviour of :code:`make install`.
+#
+#    This is a cmake builtin command.
+#    For detailed information, check the cmake documentation:
+#
+#    .. code-block: bash
+#
+#       cmake --help-command install
+#
+# .. cmake_function:: add_executable
+#
+#    Adds an executable to the project.
+#
+#    This is a cmake builtin command.
+#    For detailed information, check the cmake documentation:
+#
+#    .. code-block: bash
+#
+#       cmake --help-command add_executable
+#
+# .. cmake_function:: add_test
+#
+#    Adds a test to the testing suite.
+#
+#    This is a cmake builtin command.
+#    For detailed information, check the cmake documentation:
+#
+#    .. code-block: bash
+#
+#       cmake --help-command add_test
+#
+# .. cmake_variable:: CMAKE_<LANG>_COMPILER
+#
+#    Set the compiler for the language LANG.
+#    LANG is in our case out of C, CXX.
+#
+#    This is a cmake builtin variable.
+#    For detailed information, check the cmake documentation:
+#
+#    .. code-block: bash
+#
+#       cmake --help-variable CMAKE_\<LANG\>_COMPILER
+#
+# .. cmake_variable:: CMAKE_<LANG>_FLAGS
+#
+#    Set the compile flags for the language LANG.
+#    LANG is in our case out of C, CXX.
+#
+#    This is a cmake builtin variable.
+#    For detailed information, check the cmake documentation:
+#
+#    .. code-block: bash
+#
+#       cmake --help-variable CMAKE_\<LANG\>_FLAGS
+#
+# .. cmake_function:: find_package
+#
+#    Look for an external package.
+#
+#    This is a cmake builtin command.
+#    For detailed information, check the cmake documentation:
+#
+#    .. code-block: bash
+#
+#       cmake --help-command find_package
+#
diff --git a/doc/buildsystem/dune-common.rst b/doc/buildsystem/dune-common.rst
index 3153030a07cf6925fb0e290635e787dedab28d63..844c6e22632e87f1451546f8509ea745808c052c 100644
--- a/doc/buildsystem/dune-common.rst
+++ b/doc/buildsystem/dune-common.rst
@@ -227,7 +227,7 @@ How do I change my compiler and compiler flags?
 
 In general, there are multiple ways to do this:
 
-* Setting the CMake variables :ref:`CMAKE_C_COMPILER` and :ref:`CMAKE_CXX_COMPILER` resp. from the opts file
+* Setting the CMake variables :ref:`CMAKE_<LANG>_COMPILER` (with :code:`LANG` being :code:`C` or :code:`CXX`) from the opts file
 * Setting those variables within the project with the :code:`set` command
 * Setting the environment variables :code:`CC`, :code:`CXX` etc.
 
@@ -236,7 +236,7 @@ directories. For some CMake versions, there is a known CMake bug, that requires
 to your compiler, but Dune will issue a warning, if you violate that.
 
 You can modify your default compiler flags by setting the variables
-:ref:`CMAKE_C_FLAGS` and :ref:`CMAKE_CXX_FLAGS` in your opts file.
+:ref:`CMAKE_<LANG>_FLAGS` in your opts file (again with :code:`LANG` being :code:`C` or :code:`CXX`).
 
 .. _symlink: