diff --git a/Dockerfile b/Dockerfile
index 8fb4cd0..547201e 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -17,7 +17,7 @@ RUN apt-get update && apt-get upgrade -y && apt-get install -y sudo vim git zsh
     echo "${USERNAME} ALL=(ALL) NOPASSWD:ALL" >> /etc/sudoers && \
     ln -fs /usr/share/zoneinfo/${TIMEZONE} /etc/localtime
 
-USER $USERNAME
-WORKDIR /home/$USERNAME
+USER ${USERNAME}
+WORKDIR /home/${USERNAME}
 
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