diff --git a/roles/pycobertura-diff/tasks/main.yaml b/roles/pycobertura-diff/tasks/main.yaml
new file mode 100644
index 0000000..f86e739
--- /dev/null
+++ b/roles/pycobertura-diff/tasks/main.yaml
@@ -0,0 +1,36 @@
+- name: Ensure pycobertura is available
+  pip:
+    name: pycobertura
+    extra_args: --user
+
+- name: Prepare copy of the new version of sources
+  shell: |
+    set -ex
+    NEW_WORK={{ ansible_user_dir }}/new
+    mkdir "${NEW_WORK}"
+    NEW_SRCDIR=${NEW_WORK}/{{ zuul.project.short_name }}
+    pushd {{ zuul.project.src_dir }}
+    git worktree add "${NEW_SRCDIR}" {{ zuul.branch }}
+    popd
+
+- name: Retrieve coverage from parent jobs
+  get_url:
+    url: "{{ item.url }}"
+    dest: "{{ ansible_user_dir }}/new/coverage.xml"
+  when:
+    - item.metadata is defined
+    - item.metadata.type is defined
+    - item.metadata.type == "cobertura_xml"
+  loop: "{{ zuul.artifacts }}"
+
+- name: Generate pycobertura report
+  shell: |
+    set -ex
+    PATH=${PATH}:~/.local/bin
+    pycobertura show --format html --output "{{ ansible_user_dir }}/zuul-output/logs/coverage.html" \
+      --source "{{ ansible_user_dir }}/new/{{ zuul.project.short_name }}" "{{ ansible_user_dir }}/new/coverage.xml"
+    pycobertura diff --format html --output "{{ ansible_user_dir }}/zuul-output/logs/coverage-diff.html" \
+      --source1 "{{ zuul.project.src_dir }}" "{{ coverage_xml_dir }}/coverage.xml" \
+      --source2 "{{ ansible_user_dir }}/new/{{ zuul.project.short_name }}" "{{ ansible_user_dir }}/new/coverage.xml"
+    sed -e 's;^  </body>$;    <p>Show <a href="coverage.html">final coverage</a> only</p>\n  </body>;' \
+      -i "{{ ansible_user_dir }}/zuul-output/logs/coverage-diff.html"