diff --git a/Dockerfile b/Dockerfile
index e4da152..2f380e3 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -11,6 +11,7 @@ RUN curl -L -o elm.gz https://mirror.ghproxy.com/https://github.com/elm/compiler
 # install elm-format
 RUN curl -L -o elm-format.tgz https://mirror.ghproxy.com/https://github.com/avh4/elm-format/releases/download/0.8.7/elm-format-0.8.7-linux-x64.tgz \
     && tar -xvf elm-format.tgz \
+    && rm elm-format.tgz \
     && chmod +x elm-format \
     && mv elm-format /usr/local/bin/