diff --git a/deploy/migrations/m0039_human_tasks_expired_at.json b/deploy/migrations/m0039_human_tasks_expired_at.json
new file mode 100644
index 0000000..3361f90
--- /dev/null
+++ b/deploy/migrations/m0039_human_tasks_expired_at.json
@@ -0,0 +1,21 @@
+{
+  "id": "m0039",
+  "title": "修 pipeline_human_tasks.expired_at 创建即过期地雷(2026-09-18 银联事故实锤): 列 DDL 默认 current_timestamp() 而两处 create_human_task 均不显式写 → 实测全部历史待办 expired_at==created_at(创建瞬间过期)。本迁移①列默认改为 NOW()+7 天(MariaDB 10.6 支持表达式默认)②存量 pending 待办 expired_at 补为 created_at+7 天。代码侧两处 create_human_task 同步显式写 expired_at(双保险,不依赖列默认)",
+  "backup_tables": ["pipeline_human_tasks"],
+  "up": [
+    {
+      "op": "sql",
+      "sql": "ALTER TABLE pipeline_human_tasks MODIFY expired_at TIMESTAMP NOT NULL DEFAULT (CURRENT_TIMESTAMP + INTERVAL 7 DAY)"
+    },
+    {
+      "op": "sql",
+      "sql": "UPDATE pipeline_human_tasks SET expired_at = created_at + INTERVAL 7 DAY WHERE status='pending' AND expired_at <= created_at"
+    }
+  ],
+  "down": [
+    {
+      "op": "sql",
+      "sql": "ALTER TABLE pipeline_human_tasks MODIFY expired_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP"
+    }
+  ]
+}