diff --git a/Dockerfile b/Dockerfile
index 25ef180..b9405c8 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,6 +1,8 @@
 FROM python:3.8.5
 
-RUN apt-get install -y emacs git && \
+RUN apt-get update && \
+    apt-get install -y emacs git && \
+    apt-get autoclean && \
     pip install 'Nikola[extras]' && \
     mkdir -p ~/.emacs.d/.local/straight/build && \
     git clone https://github.com/hniksic/emacs-htmlize.git ~/.emacs.d/.local/straight/build/htmlize