diff --git a/.github/workflows/publish.yml b/.github/workflows/publish.yml
index 3673c6e..944678e 100644
--- a/.github/workflows/publish.yml
+++ b/.github/workflows/publish.yml
@@ -20,7 +20,7 @@ jobs:
     - name: Build wheels
       uses: RalfG/python-wheels-manylinux-build@v0.4.2-manylinux2014_x86_64
       with:
-        python-versions: 'cp36-cp36m cp37-cp37m cp38-cp38 cp39-cp39 cp310-cp310'
+        python-versions: 'cp37-cp37m cp38-cp38 cp39-cp39 cp310-cp310 cp311-cp311'
         build-requirements: 'cython'
     - name: Clean linux_x86_64.whl
       run: rm dist/*-linux_x86_64.whl
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index e50c5ea..afd45c0 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        pyver: ["2.7", "3.6", "3.7", "3.8", "3.9", "3.10"]
+        pyver: ["3.7", "3.8", "3.9", "3.10", "3.11"]
 
     steps:
     - uses: actions/checkout@v2
@@ -22,7 +22,7 @@ jobs:
     - name: Install python dependencies
       run: |
         python -m pip install --upgrade pip
-        pip install Cython tox
+        pip install 'Cython<3' 'tox<4'
 
     - name: Run unittest
       run: |
diff --git a/req.txt b/req.txt
index b4932e1..4dc4307 100644
--- a/req.txt
+++ b/req.txt
@@ -1,2 +1,2 @@
-cython >= 0.18
+cython >= 0.18, < 3
 gevent
diff --git a/setup.py b/setup.py
index 8b334a1..7b76a75 100644
--- a/setup.py
+++ b/setup.py
@@ -1,7 +1,7 @@
 from glob import glob
 from setuptools import setup, Extension
 
-version = "0.4.0"
+version = "0.4.1"
 
 
 def readme():
@@ -25,11 +25,11 @@ def readme():
         "Programming Language :: C",
         "Programming Language :: Cython",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.6",
         "Programming Language :: Python :: 3.7",
         "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
+        "Programming Language :: Python :: 3.11",
         "Programming Language :: Python :: Implementation :: CPython",
         "Development Status :: 5 - Production/Stable",
         "Operating System :: POSIX :: Linux",
@@ -41,7 +41,7 @@ def readme():
     author_email="tianzhongbo@douban.com",
     url="https://github.com/douban/greenify",
     download_url="https://github.com/douban/greenify/archive/%s.tar.gz" % version,
-    setup_requires=["Cython >= 0.18"],
+    setup_requires=["Cython >= 0.18, < 3"],
     install_requires=["gevent"],
     ext_modules=[
         Extension(
diff --git a/tox.ini b/tox.ini
index 496c2d9..96ec20e 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-envlist = py27, py35, py36, py37, py38, py39, py310
+envlist = py37, py38, py39, py310, py311
 
 [testenv]
 passenv = CC LD