diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 8d09ced..1c09e10 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -10,13 +10,14 @@ jobs:
   check-messages:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - uses: kaste/upgrade-messages-test-action@v1
 
   lint:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
+    - run: pip install "flake8<6.0.0"
     - uses: TrueBrain/actions-flake8@v2
 
   mypy:
@@ -26,11 +27,11 @@ jobs:
         platform: ['linux', 'darwin', 'win32']
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Set up Python
-      uses: actions/setup-python@v4
+      uses: actions/setup-python@v5
       with:
-        python-version: '3.10'
+        python-version: '3.12'
     - name: Install mypy
       run: |
         pip install mypy
@@ -42,12 +43,9 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        st-version: [3, 4]
         os: ["ubuntu-latest", "windows-latest"]
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
       - uses: SublimeText/UnitTesting/actions/setup@v1
-        with:
-          sublime-text-version: ${{ matrix.st-version }}
       - uses: SublimeText/UnitTesting/actions/run-tests@v1
diff --git a/.python-version b/.python-version
new file mode 100644
index 0000000..cc1923a
--- /dev/null
+++ b/.python-version
@@ -0,0 +1 @@
+3.8
diff --git a/messages.json b/messages.json
index 92b761f..60cf457 100644
--- a/messages.json
+++ b/messages.json
@@ -1,4 +1,5 @@
 {
     "install": "messages/install.md",
-    "0.7.0": "messages/0.7.0.md"
-}
\ No newline at end of file
+    "0.7.0": "messages/0.7.0.md",
+    "0.9.0": "messages/0.9.0.md"
+}
diff --git a/messages/0.9.0.md b/messages/0.9.0.md
new file mode 100644
index 0000000..5a5f80a
--- /dev/null
+++ b/messages/0.9.0.md
@@ -0,0 +1,6 @@
+# PyTest 0.9.0
+
+The plugin has been updated to run on Sublime Text's python38 host.
+
+A restart is required as Package Control (likely) needs to download and install
+a new `lxml` version.  Just check Sublime's console (`View > Show Console`).
diff --git a/mypy.ini b/mypy.ini
index ddb0131..735ea94 100644
--- a/mypy.ini
+++ b/mypy.ini
@@ -7,6 +7,8 @@ mypy_path =
     stubs,
     ..
 sqlite_cache = True
+implicit_optional = True
+no_namespace_packages = True
 
 [mypy-Default]
 ignore_missing_imports = True
diff --git a/util.py b/util.py
index 139dc58..1dcde18 100644
--- a/util.py
+++ b/util.py
@@ -41,14 +41,14 @@ def tweak_theme():
 
     theme = view.settings().get('theme')
     if theme is None:
-        print("Can't guess current theme.")
+        print("PyTest: Can't guess current theme.")
         return
 
     if theme == 'auto':
         print(
-            "Not implemented for 'auto'.  "
+            "PyTest: Theme patching is not implemented for 'auto'.  "
             "https://github.com/kaste/PyTest/issues/38  \n"
-            "You could try an implementation and send a pull request.")
+            "You could try an implementation and make a pull request.")
         return
 
     theme_path = os.path.join(sublime.packages_path(), 'User', theme)