diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index e7c06f1..07142e7 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -54,8 +54,6 @@ jobs:
           echo "leaf=$leaf" >> "$GITHUB_OUTPUT"
   lint:
     # Static checks are interpreter-version agnostic; run them once.
-    needs: changes
-    if: needs.changes.outputs.leaf != 'true'
     runs-on: [self-hosted, linux, x64, spikeforge-ci]
     steps:
       - uses: actions/checkout@v4
@@ -84,12 +82,11 @@ jobs:
   test:
     # The full suite across every supported interpreter (python_requires).
     needs: changes
-    if: needs.changes.outputs.leaf != 'true'
     runs-on: [self-hosted, linux, x64, spikeforge-ci]
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.10", "3.11", "3.12", "3.13"]
+        python-version: ${{ fromJSON(needs.changes.outputs.leaf == 'true' && '["3.12"]' || '["3.10", "3.11", "3.12", "3.13"]') }}
     steps:
       - uses: actions/checkout@v4
 
@@ -374,8 +371,6 @@ jobs:
     #
     # Deliberately torch-free: readme_renderer plus the stdlib is the whole
     # dependency set, so this stays one of the fastest jobs in the matrix.
-    needs: changes
-    if: needs.changes.outputs.leaf != 'true'
     runs-on: [self-hosted, linux, x64, spikeforge-ci]
     steps:
       - uses: actions/checkout@v4
@@ -428,8 +423,6 @@ jobs:
     # The static half of the core boundary: no module-level import of a
     # forbidden root, and no function-local import outside the lazy shims.
     # Pure stdlib, so no dependencies are installed.
-    needs: changes
-    if: needs.changes.outputs.leaf != 'true'
     runs-on: [self-hosted, linux, x64, spikeforge-ci]
     steps:
       - uses: actions/checkout@v4
@@ -509,8 +502,6 @@ jobs:
   packaging-guards:
     # The three lightweight topology guards: disjoint import roots (PEP 420),
     # console-script ownership, and satellite pins == compatibility.json.
-    needs: changes
-    if: needs.changes.outputs.leaf != 'true'
     runs-on: [self-hosted, linux, x64, spikeforge-ci]
     steps:
       - uses: actions/checkout@v4