diff --git a/Dockerfile b/Dockerfile
index 58308dd..528d55f 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -56,7 +56,7 @@ RUN echo "deb https://notesalexp.org/tesseract-ocr/stretch/ stretch main" >> /et
 COPY hocrtotei /usr/local/bin
 COPY ocr /usr/local/bin
 
-mkdir /input /output
-chmod a+rw /input /output
+RUN mkdir /input /output && \
+    chmod a+rw /input /output
 
 ENTRYPOINT ["ocr"]