diff --git a/Dockerfile b/Dockerfile
index c409fcb..532664e 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -5,8 +5,6 @@ ARG UID=911
 ARG GID=911
 ENV UID=911 GID=911 MIX_ENV=prod
 
-ENV MIX_ENV=prod
-
 RUN echo "http://nl.alpinelinux.org/alpine/latest-stable/community" >> /etc/apk/repositories \
     && apk update \
     && apk add git gcc g++ musl-dev make cmake file-dev \