diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 61a83a6f..263afc69 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -17,7 +17,6 @@ jobs:
       fail-fast: false
       matrix:
         python-version:
-          - "3.9"
           - "3.10"
           - "3.11"
           - "3.12"
diff --git a/makefile b/makefile
index fb83a71c..c0af37df 100644
--- a/makefile
+++ b/makefile
@@ -25,7 +25,6 @@ venv: .venv
 
 test:
 	python -m $(PKG).tests
-	python -m mypy -p $(PKG)
 	pyrefly check -c pyproject.toml
 
 lint:
diff --git a/pyproject.toml b/pyproject.toml
index b59fbf20..5ef89d67 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -23,7 +23,7 @@ classifiers = [
     "Topic :: Software Development :: Quality Assurance",
 ]
 
-requires-python = ">=3.9"
+requires-python = ">=3.10"
 dependencies = [
     "click >= 8.0, < 8.2",
     "libcst >= 0.3.18",
@@ -44,11 +44,10 @@ docs = [
 ]
 dev = [
     "attribution == 1.8.0",
-    "black == 25.11.0",
+    "black == 26.3.1",
     "build > 1",
     "flake8 == 7.3.0",
     "flake8-bugbear == 24.12.12",
-    "mypy == 1.19.1",
     "ufmt == 2.8.0",
     "usort == 1.0.8.post1",
     "pyrefly == 0.63.1",
@@ -100,12 +99,6 @@ exclude = [
     "/legacy",
 ]
 
-[tool.mypy]
-strict = true
-python_version = "3.9"
-ignore_missing_imports = true
-warn_unused_ignores = false
-
 [tool.pyrefly]
 project_includes = [
     # Start by adding a single file and we'll expand as we go