diff --git a/pyperformance/_pyproject_toml.py b/pyperformance/_pyproject_toml.py
index 06fc4096..0d0f11ca 100644
--- a/pyperformance/_pyproject_toml.py
+++ b/pyperformance/_pyproject_toml.py
@@ -20,7 +20,7 @@
 import packaging.version
 
 try:
-    import tomllib  # type: ignore[import] # tomllib doesn't exist on 3.7-3.10
+    import tomllib  # type: ignore[import-not-found] # tomllib doesn't exist on 3.7-3.10
 except ImportError:
     import tomli as tomllib
 
diff --git a/pyproject.toml b/pyproject.toml
index a64337fe..47682401 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -72,8 +72,8 @@ dependencies = [
 ]
 
 optional-dependencies.dev = [
-  "mypy==1.2",
-  "tomli",     # Needed even on 3.11+ for typechecking with mypy
+  "mypy==1.17.1",
+  "tomli",        # Needed even on 3.11+ for typechecking with mypy
   "tox",
 ]
 urls = { Homepage = "https://github.com/python/pyperformance" }