--- a/taskcluster/docker/android-build/Dockerfile
+++ b/taskcluster/docker/android-build/Dockerfile
@@ -68,19 +68,17 @@ RUN apt-get update && \
       sudo \
       tar \
       unzip \
       uuid \
       vim \
       wget \
       xz-utils \
       yasm \
-      zip \
-    && \
-    apt-get clean
+      zip
 
 # %include python/mozbuild/mozbuild/action/tooltool.py
 COPY topsrcdir/python/mozbuild/mozbuild/action/tooltool.py /setup/tooltool.py
 
 # %include testing/mozharness/external_tools/robustcheckout.py
 COPY topsrcdir/testing/mozharness/external_tools/robustcheckout.py /usr/local/mercurial/robustcheckout.py
 
 # %include taskcluster/docker/recipes/hgrc
@@ -127,19 +125,17 @@ USER root
 
 # Install Sonatype Nexus.  Cribbed directly from
 # https://github.com/sonatype/docker-nexus/blob/fffd2c61b2368292040910c055cf690c8e76a272/oss/Dockerfile.
 
 # Observe missing --no-install-recommends, in order to install glib2.0/gconf/etc.
 RUN apt-get install \
       libgconf2-4 \
       libgnome2-0 \
-      openjdk-8-jdk-headless \
-    && \
-    apt-get clean
+      openjdk-8-jdk-headless
 
 ENV NEXUS_VERSION=2.12.0-01 \
     NEXUS_SHA1SUM=1a9aaad8414baffe0a2fd46eed1f41b85f4049e6 \
     NEXUS_WORK=/builds/worker/workspace/nexus
 
 RUN mkdir -p /opt/sonatype/nexus
 
 WORKDIR /tmp

--- a/taskcluster/docker/debian7-build/Dockerfile
+++ b/taskcluster/docker/debian7-build/Dockerfile
@@ -93,19 +93,17 @@ RUN apt-get update && \
       libfreetype6-dev:$ARCH \
       libgconf2-dev:$ARCH \
       libgtk-3-dev:$ARCH \
       libgtk2.0-dev:$ARCH \
       libpango1.0-dev:$ARCH \
       libpulse-dev:$ARCH \
       libx11-xcb-dev:$ARCH \
       libxss-dev:$ARCH \
-      libxt-dev:$ARCH \
-    && \
-    apt-get clean
+      libxt-dev:$ARCH
 
 # %include testing/mozharness/external_tools/robustcheckout.py
 COPY topsrcdir/testing/mozharness/external_tools/robustcheckout.py /usr/local/mercurial/robustcheckout.py
 
 # %include taskcluster/docker/recipes/hgrc
 COPY topsrcdir/taskcluster/docker/recipes/hgrc /etc/mercurial/hgrc.d/mozilla.rc
 
 # Add pip configuration, among other things.

--- a/taskcluster/docker/toolchain-build/Dockerfile
+++ b/taskcluster/docker/toolchain-build/Dockerfile
@@ -75,19 +75,17 @@ RUN apt-get update && \
       subversion \
       tar \
       unzip \
       uuid \
       uuid-dev \
       wget \
       xz-utils \
       zip \
-      zlib1g-dev \
-    && \
-    apt-get clean
+      zlib1g-dev
 
 # %include testing/mozharness/external_tools/robustcheckout.py
 COPY topsrcdir/testing/mozharness/external_tools/robustcheckout.py /usr/local/mercurial/robustcheckout.py
 
 # %include taskcluster/docker/recipes/hgrc
 COPY topsrcdir/taskcluster/docker/recipes/hgrc /etc/mercurial/hgrc.d/mozilla.rc
 
 # Add pip configuration, among other things.