diff --git a/achievement/management/commands/recompute_achievements.py b/achievement/management/commands/recompute_achievements.py
new file mode 100644
index 0000000..d73b029
--- /dev/null
+++ b/achievement/management/commands/recompute_achievements.py
@@ -0,0 +1,62 @@
+"""全量重算指标并补发成就。
+
+用途：
+1. 系统首次上线，给存量用户补发（用 --silent，否则学生一登录被 30 个奖杯糊脸）
+2. 新增指标或改了口径后重算（不带 --silent，新解锁会正常弹出）
+
+这也是增量逻辑的安全网：怀疑 UserStat 漂移时跑一遍即可。
+"""
+
+from django.core.management.base import BaseCommand
+
+from account.models import User
+from achievement import checker
+from achievement.metrics import META_METRICS, METRIC_REGISTRY
+from achievement.models import UserStat
+
+
+class Command(BaseCommand):
+    help = "重算全部用户的成就指标并补发成就"
+
+    def add_arguments(self, parser):
+        parser.add_argument("--user", type=int, default=None, help="只处理指定用户 id")
+        parser.add_argument("--silent", action="store_true", help="补发的成就标记为已通知，不弹窗")
+
+    def handle(self, *args, **options):
+        users = User.objects.filter(is_disabled=False)
+        if options["user"]:
+            users = users.filter(id=options["user"])
+
+        silent = options["silent"]
+        total_users = users.count()
+        total_unlocked = 0
+
+        for index, user in enumerate(users.iterator(), start=1):
+            stat, _ = UserStat.objects.get_or_create(user=user)
+            metrics = {}
+            for key, m in METRIC_REGISTRY.items():
+                if key in META_METRICS:
+                    continue
+                value = m.recompute(user)
+                # None 表示该指标无有效值，key 必须缺席而不是置 0
+                if value is not None:
+                    metrics[key] = value
+            stat.metrics = metrics
+            stat.save(update_fields=["metrics", "update_time"])
+
+            records = checker.unlock(user, checker.evaluate(user, metrics), backfilled=True, notified=silent)
+
+            # 元指标第二轮
+            for key in META_METRICS:
+                value = METRIC_REGISTRY[key].recompute(user)
+                if value is not None:
+                    metrics[key] = value
+            stat.metrics = metrics
+            stat.save(update_fields=["metrics", "update_time"])
+            records += checker.unlock(user, checker.evaluate(user, metrics, only_metrics=META_METRICS), backfilled=True, notified=silent)
+
+            total_unlocked += len(records)
+            if index % 50 == 0:
+                self.stdout.write(f"processed {index}/{total_users}")
+
+        self.stdout.write(self.style.SUCCESS(f"完成：{total_users} 个用户，新解锁 {total_unlocked} 条"))