diff --git a/chromium/chromium-update.dockerfile b/chromium/chromium-update.dockerfile
index da0d8c0..ef1da58 100644
--- a/chromium/chromium-update.dockerfile
+++ b/chromium/chromium-update.dockerfile
@@ -13,4 +13,4 @@ RUN cd /home/user/chromium/src \
  && git fetch origin \
  && git reset --hard origin/master \
  && gclient sync --delete --jobs=`nproc` \
- && ninja -C out/Default chrome -j`nproc`
+ && ninja -C out/Default chrome
diff --git a/chromium/chromium.dockerfile b/chromium/chromium.dockerfile
index 339b885..485b11a 100644
--- a/chromium/chromium.dockerfile
+++ b/chromium/chromium.dockerfile
@@ -6,6 +6,10 @@ ENV PATH $PATH:/home/user/depot_tools
 RUN echo "\n# Add Chromium's depot_tools to the PATH." >> .bashrc \
  && echo "export PATH=\"\$PATH:/home/user/depot_tools\"" >> .bashrc
 
+# Make default Ninja parallelism use 8 parallel jobs.
+# TODO(phistuck) - remove this once host-level affinity settings are implemented.
+RUN echo "\nalias ninja='ninja -j8'" >> .bash_aliases
+
 # Enable bash completion for git cl.
 RUN echo "\n# The next line enables bash completion for git cl." >> .bashrc \
  && echo "if [ -f \"/home/user/depot_tools/git_cl_completion.sh\" ]; then" >> .bashrc \