diff --git a/.cirrus.yml b/.cirrus.yml
index caa938c..3d060f9 100644
--- a/.cirrus.yml
+++ b/.cirrus.yml
@@ -93,8 +93,10 @@ linux_mac_task:
     - name: test (Linux - 3.9)
       container: {image: "python:3.9-buster"}
     - name: test (Linux - 3.10)
-      allow_failures: true  # Some packages (e.g. Sphinx) might still have some problems
       container: {image: "python:3.10-buster"}
+    - name: test (Linux - 3.11)
+      allow_failures: true  # Some packages (e.g. Sphinx) might still have some problems
+      container: {image: "python:3.11-rc-buster"}
     - name: test (Linux - Anaconda)
       container: {image: "continuumio/anaconda3:2021.05"}
       env:
@@ -183,15 +185,16 @@ windows_task:
 
 
 coverage_task:
-  name: coverage (Linux - 3.6)
+  name: coverage (Linux - 3.8)
   clone_script: *clone
-  container: {image: "python:3.6-buster"}
+  container: {image: "python:3.8-buster"}
   env:
     COVERAGE: yes
   depends_on:
-    - test (Linux - 3.6)
     - test (Linux - 3.7)
     - test (Linux - 3.8)
+    - test (Linux - 3.9)
+    - test (Linux - 3.10)
     - test (Linux - Anaconda)
     - test (OS X)
   pip_install_script:
diff --git a/.coveragerc b/.coveragerc
index 533b2fc..17673cc 100644
--- a/.coveragerc
+++ b/.coveragerc
@@ -1,28 +1,10 @@
 # .coveragerc to control coverage.py
 [run]
 branch = True
-source = markdown
+source = pyscaffoldext.markdown
 # omit = bad_file.py
 
 [paths]
 source =
     src/
     */site-packages/
-
-[report]
-# Regexes for lines to exclude from consideration
-exclude_lines =
-    # Have to re-enable the standard pragma
-    pragma: no cover
-
-    # Don't complain about missing debug-only code:
-    def __repr__
-    if self\.debug
-
-    # Don't complain if tests don't hit defensive assertion code:
-    raise AssertionError
-    raise NotImplementedError
-
-    # Don't complain if non-runnable code isn't run:
-    if 0:
-    if __name__ == .__main__.:
diff --git a/setup.cfg b/setup.cfg
index ed8fae9..bc495ef 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -93,7 +93,7 @@ pyscaffold.cli =
 # CAUTION: --cov flags may prohibit setting breakpoints while debugging.
 #          Comment those flags to avoid this py.test issue.
 addopts =
-    --cov pyscaffoldext.markdown --cov-report term-missing
+    --cov --cov-report term-missing
     --verbose
 norecursedirs =
     dist
diff --git a/tox.ini b/tox.ini
index 89a7c47..e457577 100644
--- a/tox.ini
+++ b/tox.ini
@@ -4,6 +4,7 @@
 [tox]
 minversion = 3.15
 envlist = default
+isolated_build = True
 
 
 [testenv]