fixes annoying locale message

base/Dockerfile

@@ -6,6 +6,14 @@ ENV COLORTERM=truecolor
 # Update
 RUN pacman -Syu --noconfirm
 
+## Before anything, avoid some annoying warnings
+RUN pacman -Sy --noconfirm glibc && \
+    echo 'en_US.UTF-8 UTF-8' > /etc/locale.gen && \
+    locale-gen
+
+ENV LANG=en_US.UTF-8
+ENV LC_ALL=en_US.UTF-8
+
 ## Configure non-root user 
 RUN pacman -S --noconfirm sudo
 RUN useradd -m -s /bin/bash -G wheel x