diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 0f66368..6a4f5ee 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -28,8 +28,6 @@ jobs:
     uses: OpenAstronomy/github-actions-workflows/.github/workflows/tox.yml@v1
     with:
       envs: |
-        - linux: py39
-        - macos: py39
         - linux: py310
         - macos: py310
         - linux: py311
diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index f41b660..018c263 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -5,12 +5,12 @@ pool:
   vmImage: 'ubuntu-latest'
 strategy:
   matrix:
-    Python38:
-      python.version: '3.8'
-    Python39:
-      python.version: '3.9'
     Python310:
       python.version: '3.10'
+    Python311:
+      python.version: '3.11'
+    Python312:
+      python.version: '3.12'
 
 steps:
 - task: UsePythonVersion@0
diff --git a/pyproject.toml b/pyproject.toml
index be5ecb2..17ca9ab 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -20,6 +20,7 @@ dependencies = [
 dynamic = [
     "version",
 ]
+requires-python = ">=3.10"
 
 [project.readme]
 file = "README.md"
@@ -37,8 +38,8 @@ test = [
 
 [build-system]
 requires = [
-    'setuptools >=60',
-    'setuptools_scm[toml] >=3.4',
+    "setuptools >=60",
+    "setuptools_scm[toml] >=3.4",
     "wheel",
 ]
 build-backend = "setuptools.build_meta"