diff --git a/alembic/versions/merge_signin_boost_main.py b/alembic/versions/merge_signin_boost_main.py
new file mode 100644
index 0000000..8838a4e
--- /dev/null
+++ b/alembic/versions/merge_signin_boost_main.py
@@ -0,0 +1,32 @@
+"""合并两个 alembic head:drop_signin_boost_record(本分支)+ merge_active_phone(main)。
+
+两条线同从 comparison_llm_cost 分叉——本分支的 ad_reward_boost_round_id → drop_signin_boost_record
+走「金币膨胀本轮累计 + 下线签到膨胀」;main 侧的 phone_rebind_log / analytics_active_idx 两支已由
+merge_active_phone 收敛。88f2380 把 main 合进本分支后,两条迁移线在 git 上汇合了、在 alembic 图上
+却没有,于是 `alembic upgrade head`(单数)报 "Multiple head revisions are present"——按 CLAUDE.md
+run.sh 启动即自动迁移,app server 会直接起不来。
+
+本迁移仅把二者收敛成单 head;**不含任何表结构 / 数据改动**(纯 merge)。
+
+Revision ID: merge_signin_boost_main
+Revises: drop_signin_boost_record, merge_active_phone
+Create Date: 2026-07-21 00:00:00.000000
+"""
+
+from collections.abc import Sequence
+
+revision: str = "merge_signin_boost_main"
+down_revision: str | Sequence[str] | None = (
+    "drop_signin_boost_record",
+    "merge_active_phone",
+)
+branch_labels: str | Sequence[str] | None = None
+depends_on: str | Sequence[str] | None = None
+
+
+def upgrade() -> None:
+    """纯合并 head,无 schema 改动。"""
+
+
+def downgrade() -> None:
+    """拆回两个 head,无 schema 改动。"""