diff --git a/.travis.yml b/.travis.yml
index 8f19c0ea..303140d4 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -95,22 +95,13 @@ install:
   - sudo apt-get install -qq dbus-x11 xterm xdotool xterm xvfb
 
   # Determine custom version.
-  - '[ "$TRAVIS_PULL_REQUEST" = false ] && AWESOME_VERSION="${TRAVIS_BRANCH}-g$(git rev-parse --short HEAD)-$(date -Iseconds)" || AWESOME_VERSION="${TRAVIS_BRANCH}-PR${TRAVIS_PULL_REQUEST}-g$(git rev-parse --short HEAD)-$(date -Iseconds)"'
+  - export AWESOME_VERSION="${TRAVIS_BRANCH}-g$(git rev-parse --short HEAD)"
+  - 'if [ "$TRAVIS_PULL_REQUEST" != false ]; then AWESOME_VERSION="${AWESOME_VERSION}-PR${TRAVIS_PULL_REQUEST}"; fi'
 
 script:
   - export CMAKE_ARGS="-DLUA_LIBRARY=${LUALIB} -DLUA_INCLUDE_DIR=/usr/include/lua${LUAPKG} -D OVERRIDE_VERSION=$AWESOME_VERSION"
   - make && sudo env PATH=$PATH make install && awesome --version && tests/run.sh
 
-# Push updated API docs for non-PRs builds on master.
-# It uses "diff -I .." to check if there are relevant changes, and then adds
-# them in two separate commits.  This allows to more easily see real changes to
-# the documentation.
 after_success:
-  - REPO_APIDOC="https://${GH_TOKEN}@github.com/awesomeWM/apidoc"
-  # Export these to not add "git config" calls to the long command.
-  - export GIT_AUTHOR_NAME="awesome-robot on Travis CI"
-  - export GIT_AUTHOR_EMAIL="awesome-robot@users.noreply.github.com"
-  - export GIT_COMMITTER_NAME="$GIT_AUTHOR_NAME"
-  - export GIT_COMMITTER_EMAIL="$GIT_AUTHOR_EMAIL"
-  # NOTE: stdout/stderr might/should be discarded to not leak sensitive information.
-  - '[ "BUILD_APIDOC" = "true" ] && [ "$TRAVIS_BRANCH" = "master" ] && [ "$TRAVIS_PULL_REQUEST" = false ] && { echo "Uploading documentation..." && cd build && git clone --quiet --branch gh-pages $REPO_APIDOC apidoc && diff -Nur apidoc doc -I "Last updated" -I "<strong>Release</strong>:" -I "(version master-" -x .git > /tmp/p1; { echo "Patch:"; cat /tmp/p1; } && cd apidoc && patch -p1 < /tmp/p1 && git add --all . && git commit -m "Update docs for $AWESOME_VERSION via Travis" && { mv .git ../doc && cd ../doc && git add --all . && git commit -m "minor: update timestamps/version" && git push --quiet origin gh-pages || echo "Uploading docs failed!"; } || echo "Documentation has not changed."; } || echo "Not uploading docs for $TRAVIS_BRANCH:$TRAVIS_PULL_REQUEST."'
+  # Push updated API docs for relevant branches, e.g. non-PRs builds on master.
+  - if [ "BUILD_APIDOC" = "true" ]; then build-utils/travis-apidoc.sh; fi
diff --git a/build-utils/travis-apidoc.sh b/build-utils/travis-apidoc.sh
new file mode 100755
index 00000000..c786b46e
--- /dev/null
+++ b/build-utils/travis-apidoc.sh
@@ -0,0 +1,102 @@
+#!/bin/sh
+#
+# Process (API) docs after a successful build on Travis (via ../.travis.yml).
+#
+# Updated/changed documentation for "master" is pushed to gh-pages.
+# In case of pull requests or other branches, it will get added to a separate branch.
+# In case of a pull request, a compare view comment will be posted.
+#
+# NOTE: stdout/stderr might/should be discarded to not leak sensitive information.
+
+echo "Post-processing (API) documentation."
+echo "TRAVIS_PULL_REQUEST: $TRAVIS_PULL_REQUEST"
+echo "TRAVIS_BRANCH: $TRAVIS_BRANCH"
+
+# GH_TOKEN won't be available for PRs from forks.
+# (http://docs.travis-ci.com/user/pull-requests/#Security-Restrictions-when-testing-Pull-Requests).
+if [ -z "GH_TOKEN" ]; then
+  echo "No GH_TOKEN available. Skipping."
+  exit
+fi
+
+# NOTE: DO NOT USE "set -x", or anything else that would reveal GH_TOKEN!
+set -e
+set +x
+
+REPO_APIDOC="https://${GH_TOKEN}@github.com/awesomeWM/apidoc"
+REPO_DIR="$PWD"
+
+# Export these to not add "git config" calls to the long command.
+export GIT_AUTHOR_NAME="awesome-robot on Travis CI"
+export GIT_AUTHOR_EMAIL="awesome-robot@users.noreply.github.com"
+export GIT_COMMITTER_NAME="$GIT_AUTHOR_NAME"
+export GIT_COMMITTER_EMAIL="$GIT_AUTHOR_EMAIL"
+
+git clone --quiet --branch gh-pages $REPO_APIDOC build/apidoc
+cd build/apidoc
+
+# This will re-use already existing branches (updated PR).
+if [ "$TRAVIS_PULL_REQUEST" != false ]; then
+  BRANCH="pr-$TRAVIS_PULL_REQUEST"
+elif [ "$TRAVIS_BRANCH" != master ]; then
+  # Use merge-base of master in branch name, to keep different branches with
+  # the same name apart.
+  BRANCH=$TRAVIS_BRANCH-$(cd ${REPO_DIR} \
+    && git fetch --unshallow origin master \
+    && git rev-parse --short $(git merge-base HEAD FETCH_HEAD || true) || true)
+else
+  BRANCH="gh-pages"
+fi
+if [ "$BRANCH" != "gh-pages" ]; then
+  git checkout -b "$BRANCH" "origin/${BRANCH}" || git checkout -b "$BRANCH"
+fi
+
+# Use a temporary branch for the two commits, which allows for a better UI.
+git checkout -b merged-update
+
+# Create a patch without irrelevant changes (version / timestamp).
+diff -Nur . ../doc -I "Last updated" -I "<strong>Release</strong>:" \
+  -I "<h2>API documentation for awesome, a highly configurable X window manager \(version .*\)\.</h2>" \
+  -x .git | patch -p1
+
+git add --all .
+if git diff --cached --exit-code --quiet; then
+  echo "Documentation has not changed."
+  exit
+fi
+
+# Commit the relevant changes.
+OLD_REV="$(git rev-parse --short HEAD)"
+COMMIT_MSG="Update docs for $AWESOME_VERSION via Travis
+
+Last commit message:
+$(cd $REPO_DIR && git log -1 --pretty=format:%s)
+
+Build URL: https://travis-ci.org/awesomeWM/awesome/builds/${TRAVIS_BUILD_ID}"
+git commit -m "[relevant] $COMMIT_MSG"
+NEW_REV="$(git rev-parse --short HEAD)"
+
+# Commit the irrelevant changes.
+mv .git ../doc
+cd ../doc
+git add --all .
+git commit -m "[boilerplate] $COMMIT_MSG"
+
+git checkout "$BRANCH"
+git merge --no-ff -m "$COMMIT_MSG" merged-update
+
+git push --quiet origin "$BRANCH"
+
+# Generate compare view links.
+COMPARE_LINKS="Compare view: https://github.com/awesomeWM/apidoc/compare/${OLD_REV}...${NEW_REV}"
+if [ "$BRANCH" != "gh-pages" ]; then
+  COMPARE_LINKS="$COMPARE_LINKS\nComparison against master (gh-pages): https://github.com/awesomeWM/apidoc/compare/gh-pages...${NEW_REV}"
+fi
+echo "Compare links:\n$COMPARE_LINKS"
+
+# Post a comment to the PR.
+if [ "$TRAVIS_PULL_REQUEST" != false ]; then
+  curl -H "Authorization: token $GH_TOKEN" \
+    -d "{\"body\": \"Documentation has been updated for this PR:\n$COMPARE_LINKS\"}" \
+    https://api.github.com/repos/awesomeWM/awesome/issues/${TRAVIS_PULL_REQUEST}/comments
+fi