diff --git a/Dockerfile b/Dockerfile
index 07a5b29..c9e7199 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -21,7 +21,7 @@ RUN useradd -m osmcal
 RUN chown osmcal /app
 
 USER osmcal
-RUN curl -sSL https://install.python-poetry.org | python3 -
+RUN pip install poetry==1.7.1
 
 # This is a hack to speed up docker builds through leveraging the layer cache.
 COPY pyproject.toml poetry.lock Makefile ./