diff --git a/.github/workflows/plugin.yml b/.github/workflows/plugin.yml
index d24086d..4353031 100644
--- a/.github/workflows/plugin.yml
+++ b/.github/workflows/plugin.yml
@@ -173,7 +173,11 @@ jobs:
           sudo apt-get install librrd-dev rrdtool libssl-dev gettext
           python -m pip install --upgrade pip setuptools wheel
           pip install -r requirements.txt
-          cd modoboa_radicale
+          cd ..
+          git clone https://github.com/modoboa/modoboa.git
+          cd modoboa
+          python setup.py develop
+          cd ../modoboa-radicale/modoboa_radicale
           django-admin compilemessages
           cd ..
           python setup.py sdist bdist_wheel
diff --git a/requirements.txt b/requirements.txt
index d513596..3ac22ab 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,3 +1,4 @@
 drf-nested-routers
 django-webpack-loader==2.0.1
+lxml==4.9.4  # FIXME: issue with version 5+
 caldav==1.3.9