--- a/taskcluster/docker/toolchain-build/Dockerfile
+++ b/taskcluster/docker/toolchain-build/Dockerfile
@@ -38,45 +38,40 @@ RUN apt-get -o Acquire::Check-Valid-Unti
       apt-transport-https \
       ca-certificates
 
 # %ARG DOCKER_IMAGE_PACKAGES
 RUN for task in $DOCKER_IMAGE_PACKAGES; do \
       echo "deb [trusted=yes] https://queue.taskcluster.net/v1/task/$task/runs/0/artifacts/public/build/ debian/" >> /etc/apt/sources.list; \
     done
 
-RUN dpkg --add-architecture i386
-
 RUN apt-get -o Acquire::Check-Valid-Until=false update -q && \
     apt-get install -yyq --no-install-recommends \
       autoconf \
       automake \
       bison \
       build-essential \
       curl \
       cmake \
       flex \
       gawk \
       gcc-multilib \
       git \
       gnupg \
       libbz2-dev \
       libssl-dev \
       libtool \
-      libx11-dev:i386 \
       make \
       mercurial \
       ninja-build \
       p7zip-full \
       procps \
-      python-dev \
       python-pip \
       python-setuptools \
       python-virtualenv \
-      scons \
       subversion \
       tar \
       unzip \
       uuid \
       uuid-dev \
       wget \
       xz-utils \
       zip \