diff --git a/.coveragerc b/.coveragerc
new file mode 100644
index 0000000..695c37e
--- /dev/null
+++ b/.coveragerc
@@ -0,0 +1,4 @@
+[run]
+omit =
+    /usr/*
+    tests/*
diff --git a/docs/devguide.rst b/docs/devguide.rst
index ef27a0f..a36f74e 100644
--- a/docs/devguide.rst
+++ b/docs/devguide.rst
@@ -32,6 +32,18 @@ When you need a proxy to access the internet, add::
 to the call.
 
 
+Measure code coverage
+---------------------
+
+To measure the code coverage of the unit tests, the ``pytest-cov`` package is
+required. On Debian systems, this is provided in ``python3-pytest-cov``.
+Once installed, run::
+
+    $ python3 -m pytest --cov --cov-report html
+
+The coverage in HTML format can then be found in `htmlcov`.
+
+
 Community Resources
 -------------------