diff --git a/docker/rivet-herwig/Dockerfile b/docker/rivet-herwig/Dockerfile
--- a/docker/rivet-herwig/Dockerfile
+++ b/docker/rivet-herwig/Dockerfile
@@ -1,34 +1,31 @@
 FROM hepstore/rivet:2.7.0
 MAINTAINER Andy Buckley <andy.buckley@cern.ch>
 
 RUN dnf install -y boost-devel
 
-RUN mkdir /code
-
-# TODO: combine RUN rules to avoid the large intermediate layers
-
-RUN cd /code && \
-    wget https://www.hepforge.org/archive/lhapdf/LHAPDF-6.2.1.tar.gz -O- | tar xz && \
-    cd LHAPDF-*/ && ./configure --prefix=/usr/local && \
-    make -j5 && make install
+RUN mkdir /code && cd /code \
+    && wget https://www.hepforge.org/archive/lhapdf/LHAPDF-6.2.1.tar.gz -O- | tar xz \
+    && cd LHAPDF-*/ && ./configure --prefix=/usr/local \
+    && make -j5 && make install \
+    && cd ../.. && rm -rf /code
 
 #RUN lhapdf install MMHT2014{,n}lo68cl
 RUN cd /usr/local/share/LHAPDF/ && \
     for pdf in MMHT2014{,n}lo68cl; do \
       wget https://lhapdf.hepforge.org/downloads?f=pdfsets/current/$pdf.tar.gz -O- | tar xz; \
     done
 
-RUN cd /code && \
-    wget https://www.hepforge.org/archive/thepeg/ThePEG-2.1.4.tar.bz2 -O- | tar xj && \
-    cd ThePEG-*/ && ./configure --enable-shared --{prefix,with-{fastjet,hepmc,lhapdf,rivet}}=/usr/local && \
-    make -j5 && make install
+RUN mkdir /code && cd /code \
+    && wget https://www.hepforge.org/archive/thepeg/ThePEG-2.1.4.tar.bz2 -O- | tar xj \
+    && cd ThePEG-*/ && ./configure --enable-shared --{prefix,with-{fastjet,hepmc,lhapdf,rivet}}=/usr/local \
+    && make -j5 && make install \
+    && cd ../.. && rm -rf /code
 
-RUN cd /code && \
-    wget https://www.hepforge.org/archive/herwig/Herwig-7.1.4.tar.bz2 -O- | tar xj && \
-    cd Herwig-*/ && \
-    ./configure --{prefix,with-{thepeg,fastjet}}=/usr/local && \
-    make -j5 && make install
-
-RUN rm -rf /code
+RUN mkdir /code && cd /code \
+    && wget https://www.hepforge.org/archive/herwig/Herwig-7.1.4.tar.bz2 -O- | tar xj \
+    && cd Herwig-*/ \
+    && ./configure --{prefix,with-{thepeg,fastjet}}=/usr/local \
+    && make -j5 && make install \
+    && cd ../.. && rm -rf /code
 
 WORKDIR /work