diff --git a/.gitignore b/.gitignore
index 1b0152c..46c4923 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 .vscode
 .build
 .deps
+docker/qemu-*
diff --git a/AUTHORS b/AUTHORS
index 352b58e..01e215c 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -4,3 +4,4 @@
 # some cases, their employer may be the copyright holder.  To see the full list
 # of contributors, see the revision history in source control.
 Falk Werner
+Osama El Hosami
diff --git a/Makefile b/Makefile
index c27b56b..adf5dfb 100644
--- a/Makefile
+++ b/Makefile
@@ -15,6 +15,7 @@ DOCKER_RUNUSER ?= $(shell id -u)
 DOCKER_RUNGROUP ?= $(shell id -g)
 
 UBUNTU_CODENAME ?= bionic
+QEMU_VERSION ?= v3.1.0-2
 
 MARCH_AMD64 := $(filter-out amd64,$(MARCH))
 MARCH_ARM32V7 := $(filter-out arm32v7,$(MARCH))
@@ -83,6 +84,13 @@ configure: $(CONFIGURE_TARGETS)
 
 %-ubuntu: CODENAME := $(UBUNTU_CODENAME)
 
+$(PROJECT_ROOT)/docker/qemu-arm-static-$(QEMU_VERSION):
+	$(SILENT) \
+	     curl -fSL -o $@ https://github.com/multiarch/qemu-user-static/releases/download/$(QEMU_VERSION)/qemu-arm-static \
+	  && chmod +x $@ 
+
+$(OUT)/docker/wsfs-builder-arm32v7-ubuntu: $(PROJECT_ROOT)/docker/qemu-arm-static-$(QEMU_VERSION)
+
 $(OUT)/docker/%: $(PROJECT_ROOT)/docker/%.dockerfile $(PROJECT_RESOURCES) | $(OUT_DIRS)
 	$(SILENT)$(DOCKER) build --rm $(DOCKER_BUILDFLAGS) --iidfile $@ --file $< --tag $*:$(VERSION) $(dir $<)
 
diff --git a/docker/qemu-arm-static b/docker/qemu-arm-static
deleted file mode 100755
index ac72a57..0000000
Binary files a/docker/qemu-arm-static and /dev/null differ
diff --git a/docker/wsfs-builder-amd64-ubuntu.dockerfile b/docker/wsfs-builder-amd64-ubuntu.dockerfile
index 0dc7dc0..7f0b310 100644
--- a/docker/wsfs-builder-amd64-ubuntu.dockerfile
+++ b/docker/wsfs-builder-amd64-ubuntu.dockerfile
@@ -4,6 +4,7 @@ FROM ubuntu:$CODENAME
 
 RUN set -x \
   && apt update \
+  && apt upgrade -y \
   && apt install --yes --no-install-recommends \
        openssl \
        ca-certificates \
@@ -11,7 +12,8 @@ RUN set -x \
        build-essential \
        cmake \
        ninja-build \
-       pkg-config
+       pkg-config \
+  && rm -rf /var/lib/apt/lists/*
 
 ARG NPROC=1
 ARG GTEST_VERSION=1.8.1
@@ -40,11 +42,13 @@ RUN set -x \
       && ./configure \
       && make -j$NPROC install) \
   && rm /tmp/fuse-$FUSE_VERSION.tar.gz \
-  && rm -rf /tmp/libfuse-fuse-$FUSE_VERSION
+  && rm -rf /tmp/libfuse-fuse-$FUSE_VERSION \
+  && rm -rf /var/lib/apt/lists/*
 
 ARG WEBSOCKETS_VERSION=3.1.0
 
 RUN set -x \
+  && apt update \
   && apt install --yes --no-install-recommends \
        libssl-dev \
   && curl -fSL https://github.com/warmcat/libwebsockets/archive/v$WEBSOCKETS_VERSION.tar.gz -o /tmp/libwebsockets-$WEBSOCKETS_VERSION.tar.gz \
@@ -53,7 +57,8 @@ RUN set -x \
       && cmake . \
       && make -j$NPROC install) \
   && rm /tmp/libwebsockets-$WEBSOCKETS_VERSION.tar.gz \
-  && rm -rf /tmp/libwebsockets-$WEBSOCKETS_VERSION
+  && rm -rf /tmp/libwebsockets-$WEBSOCKETS_VERSION \
+  && rm -rf /var/lib/apt/lists/*
 
 ARG JANSSON_VERSION=2.12
 
@@ -61,7 +66,7 @@ RUN set -x \
   && curl -fSL https://github.com/akheron/jansson/archive/v$JANSSON_VERSION.tar.gz -o /tmp/libjansson-$JANSSON_VERSION.tar.gz \
   && tar -C /tmp -xf /tmp/libjansson-$JANSSON_VERSION.tar.gz \
   && (   cd /tmp/jansson-$JANSSON_VERSION \
-      && cmake . \
+      && cmake -DJANSSON_BUILD_DOCS=OFF . \
       && make -j$NPROC install) \
   && rm /tmp/libjansson-$JANSSON_VERSION.tar.gz \
   && rm -rf /tmp/jansson-$JANSSON_VERSION
diff --git a/docker/wsfs-builder-arm32v7-ubuntu.dockerfile b/docker/wsfs-builder-arm32v7-ubuntu.dockerfile
index 519b823..fc09ef0 100644
--- a/docker/wsfs-builder-arm32v7-ubuntu.dockerfile
+++ b/docker/wsfs-builder-arm32v7-ubuntu.dockerfile
@@ -2,10 +2,11 @@ ARG CODENAME=bionic
 
 FROM arm32v7/ubuntu:$CODENAME
 
-COPY qemu-arm-static /usr/bin/
+COPY qemu-arm-static-* /usr/bin/qemu-arm-static
 
 RUN set -x \
   && apt update \
+  && apt upgrade -y \
   && apt install --yes --no-install-recommends \
        openssl \
        ca-certificates \
@@ -13,7 +14,8 @@ RUN set -x \
        build-essential \
        cmake \
        ninja-build \
-       pkg-config
+       pkg-config \
+  && rm -rf /var/lib/apt/lists/*
 
 ARG NPROC=1
 ARG GTEST_VERSION=1.8.1
@@ -42,11 +44,13 @@ RUN set -x \
       && ./configure \
       && make -j$NPROC install) \
   && rm /tmp/fuse-$FUSE_VERSION.tar.gz \
-  && rm -rf /tmp/libfuse-fuse-$FUSE_VERSION
+  && rm -rf /tmp/libfuse-fuse-$FUSE_VERSION \
+  && rm -rf /var/lib/apt/lists/*
 
 ARG WEBSOCKETS_VERSION=3.1.0
 
 RUN set -x \
+  && apt update \
   && apt install --yes --no-install-recommends \
        libssl-dev \
   && curl -fSL https://github.com/warmcat/libwebsockets/archive/v$WEBSOCKETS_VERSION.tar.gz -o /tmp/libwebsockets-$WEBSOCKETS_VERSION.tar.gz \
@@ -55,7 +59,8 @@ RUN set -x \
       && cmake . \
       && make -j$NPROC install) \
   && rm /tmp/libwebsockets-$WEBSOCKETS_VERSION.tar.gz \
-  && rm -rf /tmp/libwebsockets-$WEBSOCKETS_VERSION
+  && rm -rf /tmp/libwebsockets-$WEBSOCKETS_VERSION \
+  && rm -rf /var/lib/apt/lists/*
 
 ARG JANSSON_VERSION=2.12
 
@@ -63,7 +68,7 @@ RUN set -x \
   && curl -fSL https://github.com/akheron/jansson/archive/v$JANSSON_VERSION.tar.gz -o /tmp/libjansson-$JANSSON_VERSION.tar.gz \
   && tar -C /tmp -xf /tmp/libjansson-$JANSSON_VERSION.tar.gz \
   && (   cd /tmp/jansson-$JANSSON_VERSION \
-      && cmake . \
+      && cmake -DJANSSON_BUILD_DOCS=OFF . \
       && make -j$NPROC install) \
   && rm /tmp/libjansson-$JANSSON_VERSION.tar.gz \
   && rm -rf /tmp/jansson-$JANSSON_VERSION