diff --git a/core/base/Dockerfile b/core/base/Dockerfile
index 4972d303..4a7ffb38 100644
--- a/core/base/Dockerfile
+++ b/core/base/Dockerfile
@@ -14,6 +14,7 @@ RUN set -euxo pipefail \
   ; addgroup -Sg ${MAILU_GID} mailu \
   ; adduser -Sg ${MAILU_UID} -G mailu -h /app -g "mailu app" -s /bin/bash mailu \
   ; apk add --no-cache bash ca-certificates curl python3 tzdata \
+  ; machine="$(uname -m)" \
   ; ! [[ "${TARGETPLATFORM}" != linux/arm/v7 && \( "${machine}" == x86_64 || "${machine}" == armv8* || "${machine}" == aarch64 \) ]] \
     || apk add --no-cache --repository=http://dl-cdn.alpinelinux.org/alpine/edge/testing hardened-malloc