diff --git a/.cirrus.tasks.yml b/.cirrus.tasks.yml
index b14fe91cdb7..f0fbc600b90 100644
--- a/.cirrus.tasks.yml
+++ b/.cirrus.tasks.yml
@@ -411,7 +411,7 @@ task:
 
 
 task:
-  name: macOS - Ventura - Meson
+  name: macOS - Sonoma - Meson
 
   env:
     CPUS: 4 # always get that much for cirrusci macOS instances
@@ -420,7 +420,7 @@ task:
     # work OK. See
     # https://postgr.es/m/20220927040208.l3shfcidovpzqxfh%40awork3.anarazel.de
     TEST_JOBS: 8
-    IMAGE: ghcr.io/cirruslabs/macos-ventura-base:latest
+    IMAGE: ghcr.io/cirruslabs/macos-runner:sonoma
 
     CIRRUS_WORKING_DIR: ${HOME}/pgsql/
     CCACHE_DIR: ${HOME}/ccache
@@ -460,6 +460,11 @@ task:
   # updates macports every time.
   macports_cache:
     folder: ${MACPORTS_CACHE}
+    fingerprint_script: |
+      # Include the OS major version in the cache key.  If the OS image changes
+      # to a different major version, we need to reinstall.
+      sw_vers -productVersion | sed 's/\..*//'
+    reupload_on_changes: true
   setup_additional_packages_script: |
     sh src/tools/ci/ci_macports_packages.sh \
       ccache \
diff --git a/src/tools/ci/ci_macports_packages.sh b/src/tools/ci/ci_macports_packages.sh
index f87256e0908..03cbe48a5d6 100755
--- a/src/tools/ci/ci_macports_packages.sh
+++ b/src/tools/ci/ci_macports_packages.sh
@@ -13,7 +13,19 @@ set -e
 
 packages="$@"
 
-macports_url="https://github.com/macports/macports-base/releases/download/v2.8.1/MacPorts-2.8.1-13-Ventura.pkg"
+macos_major_version="` sw_vers -productVersion | sed 's/\..*//' `"
+echo "macOS major version: $macos_major_version"
+
+# Scan the avialable MacPorts releases to find the latest one for the
+# running macOS release.  By default we assume the first match is the most
+# recent MacPorts version but that can be changed below if it turns out to be
+# problematic or a particular MacPorts release turns out to be broken.
+macports_release_list_url="https://api.github.com/repos/macports/macports-base/releases"
+macports_version_pattern=".*"
+#macports_version_pattern="2\.9\.3"
+macports_url="$( curl -s $macports_release_list_url | grep "\"https://github.com/macports/macports-base/releases/download/v$macports_version_pattern/MacPorts-$macports_version_pattern-$macos_major_version-[A-Za-z]*\.pkg\"" | sed 's/.*: "//;s/".*//' | head -1 )"
+echo "MacPorts package URL: $macports_url"
+
 cache_dmg="macports.hfs.dmg"
 
 if [ "$CIRRUS_CI" != "true" ]; then