diff --git a/poetry.lock b/poetry.lock
index 591d0858..64addf25 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -130,6 +130,9 @@ category = "dev"
 optional = false
 python-versions = ">=3.6"
 
+[package.dependencies]
+tomli = {version = "*", optional = true, markers = "extra == \"toml\""}
+
 [package.extras]
 toml = ["tomli"]
 
@@ -444,16 +447,15 @@ testing = ["argcomplete", "hypothesis (>=3.56)", "mock", "nose", "pygments (>=2.
 
 [[package]]
 name = "pytest-cov"
-version = "2.12.1"
+version = "4.0.0"
 description = "Pytest plugin for measuring coverage."
 category = "dev"
 optional = false
-python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
+python-versions = ">=3.6"
 
 [package.dependencies]
-coverage = ">=5.2.1"
+coverage = {version = ">=5.2.1", extras = ["toml"]}
 pytest = ">=4.6"
-toml = "*"
 
 [package.extras]
 testing = ["fields", "hunter", "process-tests", "pytest-xdist", "six", "virtualenv"]
@@ -778,7 +780,7 @@ docs = ["sphinx", "sphinx-rtd-theme", "gaphor"]
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.8"
-content-hash = "a351e525404e9efaaad47bb5188a3045f6fdd59fbe444a8f4cc5ae289a4ffb29"
+content-hash = "88d4c55bbf314683e7cb23081878936c3ef27e90ca6a6c221495be738d982525"
 
 [metadata.files]
 alabaster = [
@@ -1081,8 +1083,8 @@ pytest = [
     {file = "pytest-7.1.3.tar.gz", hash = "sha256:4f365fec2dff9c1162f834d9f18af1ba13062db0c708bf7b946f8a5c76180c39"},
 ]
 pytest-cov = [
-    {file = "pytest-cov-2.12.1.tar.gz", hash = "sha256:261ceeb8c227b726249b376b8526b600f38667ee314f910353fa318caa01f4d7"},
-    {file = "pytest_cov-2.12.1-py2.py3-none-any.whl", hash = "sha256:261bb9e47e65bd099c89c3edf92972865210c36813f80ede5277dceb77a4a62a"},
+    {file = "pytest-cov-4.0.0.tar.gz", hash = "sha256:996b79efde6433cdbd0088872dbc5fb3ed7fe1578b68cdbba634f14bb8dd0470"},
+    {file = "pytest_cov-4.0.0-py3-none-any.whl", hash = "sha256:2feb1b751d66a8bd934e5edfa2e961d11309dc37b73b0eabe73b5945fee20f6b"},
 ]
 pytest-runner = [
     {file = "pytest-runner-6.0.0.tar.gz", hash = "sha256:b4d85362ed29b4c348678de797df438f0f0509497ddb8c647096c02a6d87b685"},
diff --git a/pyproject.toml b/pyproject.toml
index becff6d4..7a60833f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -39,7 +39,7 @@ gaphor = { version = "^2.7", python = "^3.9, <3.11", optional = true }
 
 [tool.poetry.dev-dependencies]
 pytest = "^7.1"
-pytest-cov = "^2.12"
+pytest-cov = "^4.0"
 pytest-runner = "^6.0"
 black = "^22.8"
 pre-commit = "^2.20"