diff --git a/Dockerfile b/Dockerfile
index d58fe13..ebafba8 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,7 +1,10 @@
 FROM odoo:19.0
 
-# Install Python testing dependencies using the system Python
-RUN python3 -m pip install --no-cache-dir \
+# Install Python testing dependencies.
+# odoo:19.0 ships Python 3.12 (Debian 12 Bookworm) which marks the system Python
+# as externally-managed (PEP 668). Use --break-system-packages for the test tools
+# — this is a single-purpose container, not a shared Python install.
+RUN python3 -m pip install --no-cache-dir --break-system-packages \
     pytest \
     pytest-odoo \
     pytest-bdd \