diff --git a/.doc/ops/CURRENT.md b/.doc/ops/CURRENT.md
index 07d5c7a5..a3383bef 100644
--- a/.doc/ops/CURRENT.md
+++ b/.doc/ops/CURRENT.md
@@ -13,6 +13,7 @@
 
 | owner | task | branch | worktree | mutex | status |
 |-------|------|--------|----------|-------|--------|
+| Cursor | 2026-09-16-gitea-nightly-docker-datadir | fix/gitea-nightly-docker-datadir | - | ci | in_progress |
 | Cursor | 2026-09-16-gitea-nightly-host-tools | fix/gitea-nightly-host-tools | - | ci | done |
 | Cursor | 2026-09-16-wave-leftovers | fix/wave-leftovers-n7-playwright-dod | - | ci | done |
 | Cursor | 2026-09-16-wave3-pu6-pu8-go-no-go | feature/wave3-pu6-pu8-go-no-go | - | architecture-docs | done |
diff --git a/.doc/ops/handoffs/2026-09-16-gitea-nightly-secrets-configured.md b/.doc/ops/handoffs/2026-09-16-gitea-nightly-secrets-configured.md
index 54637efc..273cfc83 100644
--- a/.doc/ops/handoffs/2026-09-16-gitea-nightly-secrets-configured.md
+++ b/.doc/ops/handoffs/2026-09-16-gitea-nightly-secrets-configured.md
@@ -24,8 +24,9 @@ blocker: false
 
 - label：`nightly:host`（写入 `runner/data/.runner`，勿只改 compose）
 - `network_mode: host` + `address=http://127.0.0.1:3000`（PI 只绑 `127.0.0.1:18865`，bridge 不可达）
-- 挂载 brew + 宿主机 glibc，供 host job 使用 `node` / `go` / `curl`
-- workflow：`runs-on: nightly`；artifact 用本地 tar（Gitea 不支持 upload-artifact@v4）
+- 挂载 brew + 宿主机 glibc + `/usr/bin/docker` + `/host-agent-data`（仓库 `data/`）
+- workflow：`DATA_DIR=/host-agent-data/test`；artifact 用本地 tar（Gitea 不支持 upload-artifact@v4）
+- `run-nightly-real-pi.sh`：全 SKIP / 镜像构建失败 → `infra_fail` receipt（不再 silent exit 127）
 
 ## 验证
 
diff --git a/.github/workflows/nightly-real-pi.yml b/.github/workflows/nightly-real-pi.yml
index fb01e122..0a680351 100644
--- a/.github/workflows/nightly-real-pi.yml
+++ b/.github/workflows/nightly-real-pi.yml
@@ -29,6 +29,8 @@ jobs:
       RUNNER_AUTH_TOKEN: ${{ secrets.RUNNER_AUTH_TOKEN }}
       PI_AGENT_RUNNER_AUTH_TOKEN: ${{ secrets.RUNNER_AUTH_TOKEN }}
       TEST_DATABASE_URL: ${{ secrets.NIGHTLY_TEST_DATABASE_URL }}
+      # Local act_runner mounts repo data at /host-agent-data (see /home/weichen/gitea compose).
+      DATA_DIR: /host-agent-data/test
     steps:
       - uses: actions/checkout@v4
 
diff --git a/scripts/run-nightly-real-pi.sh b/scripts/run-nightly-real-pi.sh
index 8b250267..178e8109 100755
--- a/scripts/run-nightly-real-pi.sh
+++ b/scripts/run-nightly-real-pi.sh
@@ -146,7 +146,19 @@ fi
 set -e
 
 if [[ "${TEST_RC}" -eq 0 ]]; then
-  ensure_candidate_images
+  # go test exits 0 on all-SKIP; treat that as infra (shared DATA_DIR / runner mount).
+  if ! grep -Eq '^--- PASS:' "${LOG_FILE}" && grep -Eq '^--- SKIP:' "${LOG_FILE}"; then
+    echo "all matching tests skipped (likely missing DATA_DIR/workspaces)" | tee "${EVIDENCE_DIR}/infra-tests-skipped.txt"
+    write_receipt infra_fail infra "${LOG_FILE}" "${EVIDENCE_DIR}/infra-tests-skipped.txt"
+    echo "infrastructure failure: suite skipped instead of executing" >&2
+    exit 1
+  fi
+  if ! ensure_candidate_images; then
+    echo "candidate image build failed" | tee "${EVIDENCE_DIR}/infra-image-build.txt"
+    write_receipt infra_fail infra "${LOG_FILE}" "${EVIDENCE_DIR}/infra-image-build.txt"
+    echo "infrastructure failure: candidate image build" >&2
+    exit 1
+  fi
   write_receipt pass none "${LOG_FILE}" "${EVIDENCE_DIR}/runner-health.json"
   echo "nightly real-PI PASS; receipt written for ${COMMIT:0:12}"
   exit 0