diff --git a/.ci/azure-pipelines-steps.yml b/.ci/azure-pipelines-steps.yml
index 6aeeca93..b7b094e3 100644
--- a/.ci/azure-pipelines-steps.yml
+++ b/.ci/azure-pipelines-steps.yml
@@ -12,9 +12,14 @@ steps:
     versionSpec: '$(python.version)'
   condition: ne(variables['python.version'], '')
 
+- script: |
+    type python
+    python --version
+  displayName: Show python version
+
 - script: |
     sudo apt-get update
-    sudo apt-get install -y python2-dev
+    sudo apt-get install -y python2-dev python3-pip virtualenv
   displayName: Install build deps
   condition: and(eq(variables['python.version'], ''), eq(variables['Agent.OS'], 'Linux'))
 
diff --git a/docs/changelog.rst b/docs/changelog.rst
index da5cc5e4..2878783f 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -28,6 +28,7 @@ v0.3.4.dev0
   resource leaks.
 * :gh:issue:`659` Removed :mod:`mitogen.compat.simplejson`, not needed with Python 2.7+, contained Python 3.x syntax errors
 * :gh:issue:`983` CI: Removed PyPI faulthandler requirement from tests
+* :gh:issue:`1001` CI: Fixed Debian 9 & 11 tests
 
 v0.3.3 (2022-06-03)
 -------------------
diff --git a/tests/ansible/regression/files/debian-archive-bookworm-automatic.gpg b/tests/ansible/regression/files/debian-archive-bookworm-automatic.gpg
new file mode 100644
index 00000000..ae9cfa19
Binary files /dev/null and b/tests/ansible/regression/files/debian-archive-bookworm-automatic.gpg differ
diff --git a/tests/ansible/regression/files/debian-archive-bullseye-automatic.gpg b/tests/ansible/regression/files/debian-archive-bullseye-automatic.gpg
new file mode 100644
index 00000000..66f1a94b
Binary files /dev/null and b/tests/ansible/regression/files/debian-archive-bullseye-automatic.gpg differ
diff --git a/tests/ansible/regression/issue_776__load_plugins_called_twice.yml b/tests/ansible/regression/issue_776__load_plugins_called_twice.yml
index 2eda3944..ad5bbd69 100755
--- a/tests/ansible/regression/issue_776__load_plugins_called_twice.yml
+++ b/tests/ansible/regression/issue_776__load_plugins_called_twice.yml
@@ -15,6 +15,30 @@
       when:
         - ansible_facts.pkg_mgr in ["dnf"]
 
+    - name: Switch to archive.debian.org
+      # Debian 9 has been archived https://lists.debian.org/debian-devel-announce/2023/03/msg00006.html
+      copy:
+        content: |
+          deb http://archive.debian.org/debian stretch main contrib non-free
+        dest: /etc/apt/sources.list
+        mode: u=rw,go=r
+      when:
+        - ansible_facts.distribution == "Debian"
+        - ansible_facts.distribution_major_version == "9"
+
+    - name: Add signing keys
+      copy:
+        src: "{{ item.src }}"
+        dest: "/etc/apt/trusted.gpg.d/{{ item.src | basename }}"
+        mode: u=rw,go=r
+      loop:
+        - src: debian-archive-bullseye-automatic.gpg  # Debian 11
+        - src: debian-archive-bookworm-automatic.gpg  # Debian 12
+      when:
+        # Ideally this would check for Debian 11, but distribution_major_version
+        # is unpopulated sometimes.
+        - ansible_facts.distribution == "Debian"
+
     - name: Update package index
       apt:
         update_cache: true