diff --git a/.github/workflows/verify.yml b/.github/workflows/verify.yml
index 5e0c47d..0904850 100644
--- a/.github/workflows/verify.yml
+++ b/.github/workflows/verify.yml
@@ -19,7 +19,7 @@ jobs:
 
       - uses: actions/setup-python@a26af69be951a213d495a4c3e4e4022e16d87065 # v5
         with:
-          python-version: "3.12"
+          python-version: "3.15"
 
       - uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4
         with:
@@ -127,7 +127,7 @@ jobs:
 
       - uses: actions/setup-python@a26af69be951a213d495a4c3e4e4022e16d87065 # v5
         with:
-          python-version: "3.12"
+          python-version: "3.15"
 
       - name: Conformance index (stdlib only; mutation suite first)
         env: