diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 31d1b2f67fe..69c2ba20e2e 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -215,7 +215,31 @@ jobs:
                 requires_dist: shard.requiresDist,
               }))
             : [];
-          const nodeTestNonDistShards = nodeTestShards.filter((shard) => !shard.requires_dist);
+          const blacksmith8vcpuCoreShardNames = new Set([
+            "agentic-agents",
+            "core-runtime-infra",
+            "core-runtime-media-ui",
+          ]);
+          const blacksmith4vcpuCoreShardNames = new Set([
+            "agentic-plugin-sdk",
+            "agentic-plugins",
+          ]);
+          const resolveCoreShardRunner = (shardName) => {
+            if (!isCanonicalRepository) return "ubuntu-24.04";
+            if (blacksmith8vcpuCoreShardNames.has(shardName)) {
+              return "blacksmith-8vcpu-ubuntu-2404";
+            }
+            if (blacksmith4vcpuCoreShardNames.has(shardName)) {
+              return "blacksmith-4vcpu-ubuntu-2404";
+            }
+            return "ubuntu-24.04";
+          };
+          const nodeTestNonDistShards = nodeTestShards
+            .filter((shard) => !shard.requires_dist)
+            .map((shard) => ({
+              ...shard,
+              runner: resolveCoreShardRunner(shard.shard_name),
+            }));
           const nodeTestDistShards = nodeTestShards.filter((shard) => shard.requires_dist);
 
           const manifest = {
@@ -1118,10 +1142,7 @@ jobs:
     name: ${{ matrix.check_name }}
     needs: [preflight]
     if: needs.preflight.outputs.run_checks_node_core_nondist == 'true'
-    # Keep core shards on GitHub-hosted runners. The Blacksmith pool is already
-    # occupied by build and extension shards; queueing these shards there hides
-    # actual test-speed improvements behind runner wait time.
-    runs-on: ubuntu-24.04
+    runs-on: ${{ github.repository == 'openclaw/openclaw' && matrix.runner || 'ubuntu-24.04' }}
     timeout-minutes: 60
     strategy:
       fail-fast: false
@@ -1506,7 +1527,7 @@ jobs:
     name: ${{ matrix.check_name }}
     needs: [preflight]
     if: ${{ !cancelled() && always() && needs.preflight.outputs.run_check_additional == 'true' }}
-    runs-on: ubuntu-24.04
+    runs-on: ${{ github.repository == 'openclaw/openclaw' && matrix.runner || 'ubuntu-24.04' }}
     timeout-minutes: 20
     strategy:
       fail-fast: false
@@ -1514,14 +1535,19 @@ jobs:
         include:
           - check_name: check-additional-boundaries
             group: boundaries
+            runner: ubuntu-24.04
           - check_name: check-additional-extension-channels
             group: extension-channels
+            runner: ubuntu-24.04
           - check_name: check-additional-extension-bundled
             group: extension-bundled
+            runner: blacksmith-4vcpu-ubuntu-2404
           - check_name: check-additional-extension-package-boundary
             group: extension-package-boundary
+            runner: blacksmith-8vcpu-ubuntu-2404
           - check_name: check-additional-runtime-topology-architecture
             group: runtime-topology-architecture
+            runner: ubuntu-24.04
     steps:
       - name: Checkout
         shell: bash