diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index d255f68..cda6496 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -13,7 +13,7 @@ jobs:
     uses: ./.github/workflows/tox.yml
     with:
       default_python: "3.10"
-      jobs_producing_coverage: 0
+      jobs_producing_coverage: 6
       max_python: "3.13"
       min_python: "3.10"
       run_post: echo 'Running post'
diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 0000000..f61a244
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,12 @@
+[tool.coverage.report]
+exclude_also = ["pragma: no cover", "if TYPE_CHECKING:"]
+show_missing = true
+skip_empty = true
+
+[tool.coverage.run]
+concurrency = ["multiprocessing", "thread"]
+# Do not use branch until bug is fixes:
+# https://github.com/nedbat/coveragepy/issues/605
+# branch = true
+parallel = true
+source = ["test"]
diff --git a/requirements.in b/requirements.in
index e034800..f1d51ec 100644
--- a/requirements.in
+++ b/requirements.in
@@ -3,3 +3,5 @@ cairosvg
 markdown-include
 mkdocs-ansible
 mkdocs-exclude
+coverage>=7.6.7
+pytest>=8
diff --git a/src/devtools/__init__.py b/src/devtools/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/test/test_one.py b/test/test_one.py
new file mode 100644
index 0000000..b16a0a8
--- /dev/null
+++ b/test/test_one.py
@@ -0,0 +1,5 @@
+"""Test module for the package."""
+
+
+def test_placeholder():
+    """Placeholder test."""
diff --git a/tox.ini b/tox.ini
index 5233043..2438efb 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-minversion = 4.0
+minversion = 4.6.3
 envlist =
     lint
     docs
@@ -7,14 +7,27 @@ envlist =
     ubi9
 isolated_build = True
 requires =
-    tox>=4.21.2
-    tox-uv>=1.15.0
+  tox>=4.21.2
+  tox-uv >= 1.16.0
 
 [testenv]
 commands =
-skip_install = true
+  coverage run -m pytest {posargs:\
+    -n auto \
+    -ra \
+    --showlocals \
+    --doctest-modules \
+    --durations=10 \
+    }
+  {py,py310,py311,py312,py313}: sh -c "coverage combine -a -q --data-file={envdir}/.coverage {toxworkdir}/*/.coverage.* && coverage xml --data-file={envdir}/.coverage -o {envdir}/coverage.xml --fail-under=0"
+setenv =
+  COVERAGE_FILE = {env:COVERAGE_FILE:{envdir}/.coverage.{envname}}
+  COVERAGE_PROCESS_START={toxinidir}/pyproject.toml
+skip_install = false
 usedevelop = false
 changedir = {toxinidir}
+allowlist_externals =
+  sh
 
 [testenv:docs]
 description = Build docs