diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 16d6a88f..cc128f76 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -38,6 +38,9 @@ jobs:
           - python-version: '3.13'
             toxenv: 'py313-test'
 
+          - python-version: '3.14'
+            toxenv: 'py314-test'
+
           - python-version: 'pypy-3.11'
             toxenv: 'pypy3-test'
 
@@ -65,7 +68,7 @@ jobs:
           pip install -U pip # so that we can use wheels
           # tox creates the sdist: we need cython to be installed in the env which
           # creates the sdist, to generate the .c files
-          pip install tox==4.25.0 cython==3.0.12
+          pip install tox==4.25.0 cython==3.1.7
 
       - name: Run tox
         run: tox -e ${{ matrix.toxenv }}
diff --git a/capnpy/_hash.h b/capnpy/_hash.h
index 18f29f17..dcbda235 100644
--- a/capnpy/_hash.h
+++ b/capnpy/_hash.h
@@ -25,7 +25,13 @@ typedef struct {
 
     // Use values / methods from CPython 3.5
     #define HASH_MASK _PyHASH_MODULUS
+
+    // https://groups.google.com/g/cython-users/c/YQkU8oc8oSM/m/nVJ_IX8KAgAJ
+    #if PY_VERSION_HEX < 0x030E0000
     #define strhash_f _Py_HashBytes
+    #else
+    #define strhash_f Py_HashBuffer
+    #endif
 
     // Unused in Python 3, but has to exist during cython compilation
     _Py_HashSecret_custom HashSecret;
diff --git a/setup.py b/setup.py
index 197544dd..a3ae716d 100644
--- a/setup.py
+++ b/setup.py
@@ -59,6 +59,7 @@
 """
 
 MIN_REQUIRED_CYTHON_VERSION = "0.29.30"
+MAX_CYTHON_VERSION = "3.1.7"
 
 ###############################################################################
 # Custom distutils commands
@@ -167,7 +168,7 @@ def getext(fname):
 
 if USE_CYTHON:
     ext_modules = get_cython_extensions()
-    extra_install_requires = [f'cython>={MIN_REQUIRED_CYTHON_VERSION}']
+    extra_install_requires = [f'cython>={MIN_REQUIRED_CYTHON_VERSION},<={MAX_CYTHON_VERSION}']
 else:
     ext_modules = []
     extra_install_requires = []
diff --git a/tox.ini b/tox.ini
index be29406b..ff3d9a38 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,7 +1,7 @@
 [tox]
 # nopyx is a special env where Cython is NOT installed, and thus we run
 # pure-python tests
-envlist = py37-test,py38-test,py39-test,py310-test,py311-test,py312-test,py313-test,pypy-{test,bench},pypy3-{test},docs
+envlist = py37-test,py38-test,py39-test,py310-test,py311-test,py312-test,py313-test,py314-test,pypy-{test,bench},pypy3-{test},docs
 
 [testenv]
 setenv =