diff --git a/pyproject.toml b/pyproject.toml
index 890a892..f0040b0 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -34,7 +34,7 @@ jsmin = "*"
 pytest = "*"
 black = "^20.8b1"
 isort = "*"
-flake8 = "^3.9.0"
+flake8 = "^4.0.0"
 
 [tool.poetry.scripts]
 run = "wsgi:app"