diff --git a/Containers/apache/Dockerfile b/Containers/apache/Dockerfile
index 7821fded..8073c787 100644
--- a/Containers/apache/Dockerfile
+++ b/Containers/apache/Dockerfile
@@ -17,12 +17,12 @@ RUN set -ex; \
         ca-certificates \
         openssl \
         netcat \
+        dpkg-dev \
     ; \
     rm -rf /var/lib/apt/lists/*
 
-ENV DEB_HOST_ARCH="$(dpkg-architecture --query DEB_HOST_ARCH)"
-
-RUN wget "https://caddyserver.com/api/download?os=linux&arch=$DEB_HOST_ARCH" -O "/usr/bin/caddy" \
+RUN set -ex; \
+    wget "https://caddyserver.com/api/download?os=linux&arch=$(dpkg-architecture --query DEB_BUILD_ARCH)" -O "/usr/bin/caddy" \
     && chmod +x /usr/bin/caddy \
     && /usr/bin/caddy version
 
diff --git a/Containers/mastercontainer/Dockerfile b/Containers/mastercontainer/Dockerfile
index 7a4d98e2..c0111ffd 100644
--- a/Containers/mastercontainer/Dockerfile
+++ b/Containers/mastercontainer/Dockerfile
@@ -19,12 +19,12 @@ RUN apt-get update; \
         supervisor \
         openssl \
         sudo \
+        dpkg-dev \
     ; \
     rm -rf /var/lib/apt/lists/*
 
-ENV DEB_HOST_ARCH="$(dpkg-architecture --query DEB_HOST_ARCH)"
-
-RUN curl "https://caddyserver.com/api/download?os=linux&arch=$DEB_HOST_ARCH" -o "/usr/bin/caddy" \
+RUN set -ex; \
+    curl "https://caddyserver.com/api/download?os=linux&arch=$(dpkg-architecture --query DEB_BUILD_ARCH)" -o "/usr/bin/caddy" \
     && chmod +x /usr/bin/caddy \
     && /usr/bin/caddy version