diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index ba5ced3..15a114c 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -24,4 +24,6 @@ jobs:
         pip install tox
 
     - name: Run tests
-      run: tox
+      env:
+        GITHUB_TOKEN: ${{ github.token }}
+      run: tox -e cov-ci
diff --git a/.gitignore b/.gitignore
index 3a31716..bec026d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,4 @@
 **/__pycache__/
 dist/
 .tox/
+.coverage
diff --git a/tests/test_plugin.py b/tests/test_plugin.py
new file mode 100644
index 0000000..87a839e
--- /dev/null
+++ b/tests/test_plugin.py
@@ -0,0 +1,46 @@
+# High-level test of the entire plugin.
+from unittest import mock
+import argparse
+
+from pluggy import PluginManager
+
+import pytest_filecov.plugin
+
+
+class FakePluginManager:
+    def __init__(self):
+        self.registered = None
+
+    def register(self, plugin):
+        assert not self.registered
+        self.registered = plugin
+
+
+class FakeConfig:
+    def __init__(self, filecov):
+        self.filecov = filecov
+
+    @property
+    def option(self):
+        return self
+
+
+def test_plugin_noop():
+    parser = mock.Mock(spec=["getgroup", "addoption"])
+    pm = FakePluginManager()
+    pytest_filecov.plugin.pytest_addoption(parser, pm)
+
+    # Should have registered
+    assert pm.registered
+
+    # Do a test in the case where no monitoring is requested
+    config = FakeConfig([])
+
+    plugin = pm.registered
+
+    # These should all work and do effectively nothing
+    plugin.pytest_configure(config)
+    plugin.pytest_sessionstart(object())
+    plugin.pytest_sessionfinish(object())
+    assert plugin.pytest_report_header(object(), object()) == []
+    plugin.pytest_terminal_summary(object())
diff --git a/tox.ini b/tox.ini
index 5a3c326..2b17ed6 100644
--- a/tox.ini
+++ b/tox.ini
@@ -2,4 +2,19 @@
 envlist = py38
 
 [testenv]
-commands=pytest -v {posargs}
+usedevelop=true
+deps=
+	pytest-cov
+commands=
+	pytest -v --cov=pytest_filecov {posargs}
+
+[testenv:cov-ci]
+passenv=GITHUB_*
+usedevelop=true
+deps=
+	pytest-cov
+	coveralls
+commands=
+	pytest -v --cov=pytest_filecov {posargs}
+	coveralls --service=github
+