diff --git a/Dockerfile.dapper b/Dockerfile.dapper
index 6a7a2350..fd4ce621 100644
--- a/Dockerfile.dapper
+++ b/Dockerfile.dapper
@@ -1,8 +1,13 @@
 FROM ubuntu:16.04
 # FROM arm64=aarch64/ubuntu:16.04 arm=armhf/ubuntu:16.04
 
-RUN apt-get update && \
-    apt-get install -y --no-install-recommends \
+# get the apt-cacher proxy set
+ARG APTPROXY=
+
+RUN echo "Acquire::http { Proxy \"$APTPROXY\"; };" >> /etc/apt/apt.conf.d/01proxy \
+    && cat /etc/apt/apt.conf.d/01proxy \
+    && apt-get update \
+    && apt-get install -y --no-install-recommends \
         build-essential \
         ca-certificates \
         cpio \
@@ -32,7 +37,7 @@ RUN apt-get update && \
 
 ########## Dapper Configuration #####################
 
-ENV DAPPER_ENV VERSION DEV_BUILD RUNTEST DEBUG
+ENV DAPPER_ENV VERSION DEV_BUILD RUNTEST DEBUG APTPROXY
 ENV DAPPER_DOCKER_SOCKET true
 ENV DAPPER_SOURCE /go/src/github.com/rancher/os
 ENV DAPPER_OUTPUT ./bin ./dist ./build/initrd ./build/kernel
diff --git a/scripts/installer/kexec/Dockerfile.dapper b/scripts/installer/kexec/Dockerfile.dapper
index a60d39f7..49ad5889 100644
--- a/scripts/installer/kexec/Dockerfile.dapper
+++ b/scripts/installer/kexec/Dockerfile.dapper
@@ -1,8 +1,12 @@
 FROM ubuntu:16.04
 # FROM arm64=aarch64/ubuntu:16.04 arm=armhf/ubuntu:16.04
 
+# get the apt-cacher proxy set
+ARG APTPROXY=
 
-RUN apt-get update \
+RUN echo "Acquire::http { Proxy \"$APTPROXY\"; };" >> /etc/apt/apt.conf.d/01proxy \
+    && cat /etc/apt/apt.conf.d/01proxy \
+    && apt-get update \
     && apt-get install -yq build-essential autoconf libtool gawk alien fakeroot \
         zlib1g-dev uuid-dev libattr1-dev libblkid-dev libselinux-dev libudev-dev libdevmapper-dev \
         module-init-tools \
@@ -30,7 +34,7 @@ RUN mkdir -p /source/dist \
 
 ########## Dapper Configuration #####################
 
-ENV DAPPER_ENV VERSION DEV_BUILD RUNTEST
+ENV DAPPER_ENV VERSION DEV_BUILD RUNTEST APTPROXY
 #ENV DAPPER_DOCKER_SOCKET true
 ENV DAPPER_SOURCE /source
 ENV DAPPER_OUTPUT ./dist