diff --git a/docs/contributing.rst b/docs/contributing.rst
--- a/docs/contributing.rst
+++ b/docs/contributing.rst
@@ -34,7 +34,7 @@ bash shell::
         hg clone https://kallithea-scm.org/repos/kallithea
         cd kallithea
         python3 -m venv ../kallithea-venv
-        source ../kallithea-venv/bin/activate
+        . ../kallithea-venv/bin/activate
         pip install --upgrade pip setuptools
         pip install --upgrade -e . -r dev_requirements.txt python-ldap python-pam
         kallithea-cli config-create my.ini