diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 8be7bd72..08f8d81c 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -170,7 +170,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: [3.6.7, 3.6.8, 3.6.9, 3.6.10, 3.6.11, 3.6.12, 3.6.13, 3.6.14, 3.6.15, 3.7.1, 3.7.2, 3.7.3, 3.7.4, 3.7.5, 3.7.6, 3.7.7, 3.7.8, 3.7.9, 3.7.10, 3.7.11, 3.7.12, 3.7.13, 3.7.14, 3.7.15, 3.7.16, 3.7.17, 3.8.0, 3.8.1, 3.8.2, 3.8.3, 3.8.4, 3.8.5, 3.8.6, 3.8.7, 3.8.8, 3.8.9, 3.8.10, 3.8.11, 3.8.12, 3.8.13, 3.8.14, 3.8.15, 3.8.16, 3.8.17, 3.8.18, 3.9.0, 3.9.1, 3.9.2, 3.9.3, 3.9.4, 3.9.5, 3.9.6, 3.9.7, 3.9.8, 3.9.9, 3.9.10, 3.9.11, 3.9.12, 3.9.13, 3.9.14, 3.9.15, 3.9.16, 3.9.17, 3.9.18, 3.9.19, 3.9.20, 3.10.0, 3.10.1, 3.10.2, 3.10.3, 3.10.4, 3.10.5, 3.10.6, 3.10.7, 3.10.8, 3.10.9, 3.10.10, 3.10.11, 3.10.12, 3.10.13, 3.10.14, 3.10.15, 3.11.0, 3.11.1, 3.11.2, 3.11.3, 3.11.4, 3.11.5, 3.11.6, 3.11.7, 3.11.8, 3.11.9, 3.11.10]
+        python-version: [3.6.7, 3.6.15, 3.7.1, 3.7.17, 3.8.0, 3.8.18, 3.9.0, 3.9.20, 3.10.0, 3.10.1, 3.10.2, 3.10.3, 3.10.4, 3.10.5, 3.10.6, 3.10.7, 3.10.8, 3.10.9, 3.10.10, 3.10.11, 3.10.12, 3.10.13, 3.10.14, 3.10.15, 3.11.0, 3.11.1, 3.11.2, 3.11.3, 3.11.4, 3.11.5, 3.11.6, 3.11.7, 3.11.8, 3.11.9, 3.11.10]
         os: [ubuntu-20.04, macos-13, windows-latest]
         # some versions of python can't be tested on GHA with osx because of SIP:
         exclude:
diff --git a/ci/update_python_test_versions.py b/ci/update_python_test_versions.py
index 58f50a58..6a53286d 100644
--- a/ci/update_python_test_versions.py
+++ b/ci/update_python_test_versions.py
@@ -1,3 +1,4 @@
+from collections import defaultdict
 import requests
 import pathlib
 import re
@@ -13,8 +14,10 @@ def parse_version(v):
 def get_github_python_versions():
     versions_json = requests.get(_VERSIONS_URL).json()
     raw_versions = [v["version"] for v in versions_json]
-    versions = []
-    for version_str in raw_versions: 
+
+    minor_versions = defaultdict(list)
+
+    for version_str in raw_versions:
         if "-" in version_str:
             continue
 
@@ -26,8 +29,22 @@ def get_github_python_versions():
         elif major == 2 and minor < 7:
             # we don't test python support before 2.7
             continue
+        minor_versions[(major, minor)].append(patch)
+
+    versions = []
+    for (major, minor), patches in minor_versions.items():
+        patches.sort()
+
+        # for older versions of python, don't test all patches
+        # (just test first and last) to keep the test matrix down
+        if (major == 2 or minor < 10):
+            patches = [patches[0], patches[-1]]
+
+        if (major == 3 and minor >= 12):
+            continue
+
+        versions.extend(f"{major}.{minor}.{patch}" for patch in patches)
 
-        versions.append(version_str)
     return versions
 
 
@@ -55,7 +72,7 @@ def get_github_python_versions():
     exclusions = []
     for v in versions:
         if v.startswith("3.11"):
-            exclusions.append("          - os: macos-latest\n")
+            exclusions.append("          - os: macos-13\n")
             exclusions.append(f"            python-version: {v}\n")
     test_wheels = transformed.index("  test-wheels:\n")
     first_line = transformed.index("        exclude:\n", test_wheels)