diff --git a/Dockerfile b/Dockerfile
index e12fdc9..d41a132 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -3,4 +3,5 @@ WORKDIR /data
 RUN echo "http://dl-4.alpinelinux.org/alpine/edge/main" >> /etc/apk/repositories && \
   echo "http://dl-4.alpinelinux.org/alpine/edge/community" >> /etc/apk/repositories && \
   echo "http://dl-4.alpinelinux.org/alpine/edge/testing" >> /etc/apk/repositories && \
+  apk upgrade && \
   apk add --no-cache build-base py3-unoconv imagemagick graphicsmagick curl wget git python3-dev jpeg-dev zlib-dev qpdf poppler-utils ffmpeg python bash