diff --git a/.github/actions/setup-bun/action.yml b/.github/actions/setup-bun/action.yml
index 10aac834f2..4979ebd246 100644
--- a/.github/actions/setup-bun/action.yml
+++ b/.github/actions/setup-bun/action.yml
@@ -40,10 +40,9 @@ runs:
       shell: bash
       run: echo "dir=$(bun pm cache)" >> "$GITHUB_OUTPUT"
 
-    # Restoring and extracting the ~1 GB cache took 2m23s on Windows, while a # kilocode_change
-    # fresh install took 1m27s. Keep Windows off this cache until that reverses. # kilocode_change
+    # Windows uses this cache again: the old 2m23s restore-vs-1m27s-install measurement # kilocode_change
+    # predates the Defender exclusions, which cover both the bun cache and node_modules. # kilocode_change
     - name: Restore Bun dependencies
-      if: runner.os != 'Windows' # kilocode_change
       id: bun-cache
       uses: actions/cache/restore@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0
       with:
@@ -102,9 +101,8 @@ runs:
         fi
       shell: bash
 
-    # Do not upload a Windows cache that Windows jobs intentionally never restore. # kilocode_change
     - name: Save Bun dependencies
-      if: runner.os != 'Windows' && steps.bun-cache.outputs.cache-hit != 'true' && github.event_name != 'pull_request' && github.event_name != 'pull_request_target' # kilocode_change
+      if: steps.bun-cache.outputs.cache-hit != 'true' && github.event_name != 'pull_request' && github.event_name != 'pull_request_target' # kilocode_change
       uses: actions/cache/save@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0
       with:
         path: ${{ steps.cache.outputs.dir }}
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index ddf106b237..5de2258248 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -64,10 +64,10 @@ jobs:
             exit 0
           fi
           echo 'general=true' >> "$GITHUB_OUTPUT"
-          # kilocode_change - Windows is 6 shards (was 4): CLI tests now run at KILO_TEST_CONCURRENCY=2
-          # instead of the default 4 to cut CPU contention on the 4-vCPU runner; more shards keep
-          # per-shard wall-clock within the job timeout despite the lower per-shard parallelism.
-          echo 'settings=[{"os":"linux","index":1,"total":2,"host":"blacksmith-4vcpu-ubuntu-2404","run":true,"packages":true},{"os":"linux","index":2,"total":2,"host":"blacksmith-4vcpu-ubuntu-2404","run":true,"packages":false},{"os":"macos","index":1,"total":1,"host":"macos-15","run":true,"packages":true},{"os":"windows","index":1,"total":6,"host":"blacksmith-4vcpu-windows-2025","run":true,"packages":true},{"os":"windows","index":2,"total":6,"host":"blacksmith-4vcpu-windows-2025","run":true,"packages":false},{"os":"windows","index":3,"total":6,"host":"blacksmith-4vcpu-windows-2025","run":true,"packages":false},{"os":"windows","index":4,"total":6,"host":"blacksmith-4vcpu-windows-2025","run":true,"packages":false},{"os":"windows","index":5,"total":6,"host":"blacksmith-4vcpu-windows-2025","run":true,"packages":false},{"os":"windows","index":6,"total":6,"host":"blacksmith-4vcpu-windows-2025","run":true,"packages":false}]' >> "$GITHUB_OUTPUT"
+          # kilocode_change - Windows runs 5 shards at KILO_TEST_CONCURRENCY=2: shared-process
+          # batching cut per-shard test time enough that 5 shards hold the same wall-clock as 6,
+          # saving one job's worth of fixed setup and runner-pool pressure per run.
+          echo 'settings=[{"os":"linux","index":1,"total":2,"host":"blacksmith-4vcpu-ubuntu-2404","run":true,"packages":true},{"os":"linux","index":2,"total":2,"host":"blacksmith-4vcpu-ubuntu-2404","run":true,"packages":false},{"os":"macos","index":1,"total":1,"host":"macos-15","run":true,"packages":true},{"os":"windows","index":1,"total":5,"host":"blacksmith-4vcpu-windows-2025","run":true,"packages":true},{"os":"windows","index":2,"total":5,"host":"blacksmith-4vcpu-windows-2025","run":true,"packages":false},{"os":"windows","index":3,"total":5,"host":"blacksmith-4vcpu-windows-2025","run":true,"packages":false},{"os":"windows","index":4,"total":5,"host":"blacksmith-4vcpu-windows-2025","run":true,"packages":false},{"os":"windows","index":5,"total":5,"host":"blacksmith-4vcpu-windows-2025","run":true,"packages":false}]' >> "$GITHUB_OUTPUT"
   # kilocode_change end
   unit:
     # kilocode_change start