diff --git a/pyproject.toml b/pyproject.toml
index be70a1e4..d5923592 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -45,6 +45,7 @@ tzlocal = ">=4.0"   # https://github.com/regebro/tzlocal/blob/master/CHANGES.txt
 [tool.poetry.dev-dependencies]
 black = { version = ">=21.5b2", allow-prereleases = true }
 flakeheaven = ">=3.0"
+flake8-simplify = ">=0.19"
 ipdb = "*"
 isort = ">=5.10"
 mkdocs = ">=1.0,<1.3"
@@ -169,6 +170,7 @@ pycodestyle = [
   "-E70",
   "-W1*", "-W2*", "-W3*", "-W5*",
 ]
+"flake8-*" = ["+*"]
 
 
 [build-system]