diff --git a/backend/app/__init__.py b/backend/app/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/backend/app/api/__init__.py b/backend/app/api/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/backend/app/core/__init__.py b/backend/app/core/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/backend/app/crud/__init__.py b/backend/app/crud/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/backend/app/database.py b/backend/app/database.py
new file mode 100644
index 0000000..984662a
--- /dev/null
+++ b/backend/app/database.py
@@ -0,0 +1,22 @@
+# database.py
+from sqlalchemy import create_engine
+from sqlalchemy.orm import sessionmaker
+
+# SQLite 数据库文件位置
+SQLALCHEMY_DATABASE_URL = "sqlite:///./data/demo.db"
+
+# 创建数据库引擎
+engine = create_engine(
+    SQLALCHEMY_DATABASE_URL, connect_args={"check_same_thread": False}
+)
+
+# 创建数据库会话工厂
+SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
+
+# 依赖注入函数：每个请求过来时，给它发一个数据库连接，请求结束时自动关闭
+def get_db():
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()
\ No newline at end of file
diff --git a/backend/app/main.py b/backend/app/main.py
new file mode 100644
index 0000000..161d781
--- /dev/null
+++ b/backend/app/main.py
@@ -0,0 +1,71 @@
+# app/main.py
+from contextlib import asynccontextmanager
+from fastapi import FastAPI, Depends
+from sqlalchemy.orm import Session
+
+
+from app.database import engine, get_db
+from app.models.models import Base, InfoSource, SourceType
+
+
+# ==========================================
+# 1. 生命周期管理：App 启动时自动建表
+# ==========================================
+@asynccontextmanager
+async def lifespan(app: FastAPI):
+    # 启动时执行：检查模型，如果表不存在，自动在 SQLite 中建表！
+    print("正在初始化数据库表...")
+    # ---> 核心修改 2：直接使用 Base，而不是 models.Base <---
+    Base.metadata.create_all(bind=engine)
+    print("数据库表初始化完成！")
+    yield
+
+
+
+# 初始化 FastAPI，挂载生命周期
+app = FastAPI(title="AI 新闻聚合引擎 API", lifespan=lifespan)
+
+
+# ==========================================
+# 2. 路由 API 定义
+# ==========================================
+
+@app.get("/")
+async def root():
+    return {"message": "Welcome to AI News Aggregator API"}
+
+
+@app.get("/hello/{name}")
+async def say_hello(name: str):
+    return {"message": f"Hello {name}"}
+
+
+# --->与数据库交互的真实接口
+
+@app.post("/sources/")
+async def create_info_source(name: str, url: str, db: Session = Depends(get_db)):
+    """
+    测试接口：向数据库中添加一个新闻信息源
+    """
+    # ---> 核心修改 3：直接使用 InfoSource 和 SourceType <---
+    new_source = InfoSource(
+        source_name=name,
+        source_type=SourceType.RSS_FEED,  # 默认用 RSS 测试
+        home_url=url
+    )
+
+    db.add(new_source)
+    db.commit()
+    db.refresh(new_source)  # 刷新以获取自动生成的 ID
+
+    return {"message": "创建成功！", "data": new_source}
+
+
+@app.get("/sources/")
+async def get_all_sources(db: Session = Depends(get_db)):
+    """
+    测试接口：查询数据库中所有的信息源
+    """
+    # ---> 核心修改 4：直接使用 InfoSource <---
+    sources = db.query(InfoSource).all()
+    return {"total": len(sources), "data": sources}
\ No newline at end of file
diff --git a/backend/app/models/__init__.py b/backend/app/models/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/backend/app/models/models.py b/backend/app/models/models.py
new file mode 100644
index 0000000..7108e82
--- /dev/null
+++ b/backend/app/models/models.py
@@ -0,0 +1,294 @@
+from datetime import datetime, timezone, time
+from typing import Optional, Any
+import enum
+
+from sqlalchemy import (
+    String, Integer, BigInteger, Text, Boolean, DateTime, Time,
+    Float, JSON, ForeignKey, Enum, UniqueConstraint, Index
+)
+from sqlalchemy.orm import DeclarativeBase, Mapped, mapped_column, relationship
+
+
+# ==========================================
+# 0. 全局基类与枚举定义
+# ==========================================
+
+class Base(DeclarativeBase):
+    """SQLAlchemy 2.0 声明式基类"""
+    pass
+
+
+class SourceType(str, enum.Enum):
+    HOT_TREND = "HOT_TREND"
+    RSS_FEED = "RSS_FEED"
+    API = "API"
+
+
+class TargetType(str, enum.Enum):
+    EVENT = "EVENT"
+    TREND = "TREND"
+    ARTICLE = "ARTICLE"
+
+
+class TaskStatus(str, enum.Enum):
+    SUCCESS = "SUCCESS"
+    ERROR = "ERROR"
+
+
+class GenderType(str, enum.Enum):
+    MALE = "MALE"
+    FEMALE = "FEMALE"
+    OTHER = "OTHER"
+    UNKNOWN = "UNKNOWN"
+
+
+def utcnow():
+    """获取带UTC时区的当前时间 (推荐实践)"""
+    return datetime.now(timezone.utc)
+
+
+# ==========================================
+# 模块一：信息源管理
+# ==========================================
+class InfoSource(Base):
+    __tablename__ = "info_sources"
+
+    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
+    source_name: Mapped[str] = mapped_column(String(100), comment="信息源名称")
+    source_type: Mapped[SourceType] = mapped_column(Enum(SourceType))
+    home_url: Mapped[Optional[str]] = mapped_column(String(255))
+    is_enabled: Mapped[bool] = mapped_column(Boolean, default=True)
+
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow)
+    updated_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow, onupdate=utcnow)
+
+
+# ==========================================
+# 模块二：AI 语义聚类中枢 (大事件池)
+# ==========================================
+class UnifiedEvent(Base):
+    __tablename__ = "unified_events"
+
+    id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
+    unified_title: Mapped[str] = mapped_column(String(255), comment="AI统一标题")
+    ai_comprehensive_summary: Mapped[Optional[str]] = mapped_column(Text, comment="AI全局深度总结")
+
+    # SQLite 没有原生 Vector 类型，存为用逗号分隔的字符串或JSON，Postgres可换成 PGVector
+    center_embedding: Mapped[Optional[str]] = mapped_column(Text, comment="中心向量")
+    hot_score: Mapped[int] = mapped_column(Integer, default=0, comment="聚合热度得分")
+
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow)
+    updated_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow, onupdate=utcnow)
+
+
+# ==========================================
+# 模块三：内容存储库 (热搜 & 新闻子节点)
+# ==========================================
+class TrendingEvent(Base):
+    __tablename__ = "trending_events"
+    __table_args__ = (
+        UniqueConstraint("source_id", "external_id", name="idx_unique_external_trend"),
+    )
+
+    id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
+    source_id: Mapped[int] = mapped_column(ForeignKey("info_sources.id"))
+    unified_event_id: Mapped[Optional[int]] = mapped_column(ForeignKey("unified_events.id"))
+
+    external_id: Mapped[str] = mapped_column(String(32), comment="32位MD5哈希指纹防重")
+    title_embedding: Mapped[Optional[str]] = mapped_column(Text)
+
+    icon_url: Mapped[Optional[str]] = mapped_column(String(500))
+    current_headline: Mapped[str] = mapped_column(String(255))
+    event_url: Mapped[Optional[str]] = mapped_column(String(500))
+    app_link: Mapped[Optional[str]] = mapped_column(String(500))
+    current_ranking: Mapped[Optional[int]] = mapped_column(Integer)
+    brief_snippet: Mapped[Optional[str]] = mapped_column(Text)
+
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow)
+    updated_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow, onupdate=utcnow)
+
+
+class NewsArticle(Base):
+    __tablename__ = "news_articles"
+    __table_args__ = (
+        UniqueConstraint("source_id", "external_id", name="idx_unique_external_article"),
+    )
+
+    id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
+    source_id: Mapped[int] = mapped_column(ForeignKey("info_sources.id"))
+    unified_event_id: Mapped[Optional[int]] = mapped_column(ForeignKey("unified_events.id"))
+
+    external_id: Mapped[str] = mapped_column(String(32))
+    title_embedding: Mapped[Optional[str]] = mapped_column(Text)
+
+    cover_image_url: Mapped[Optional[str]] = mapped_column(String(500))
+    article_title: Mapped[str] = mapped_column(String(255))
+    article_url: Mapped[Optional[str]] = mapped_column(String(500))
+    author_name: Mapped[Optional[str]] = mapped_column(String(100))
+    original_summary: Mapped[Optional[str]] = mapped_column(Text)
+    publish_time: Mapped[Optional[datetime]] = mapped_column(DateTime(timezone=True))
+
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow)
+    updated_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow, onupdate=utcnow)
+
+
+# ==========================================
+# 模块四：热度与轨迹追踪
+# ==========================================
+class HeadlineRevision(Base):
+    __tablename__ = "headline_revisions"
+
+    id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
+    event_id: Mapped[int] = mapped_column(ForeignKey("trending_events.id"))
+    previous_headline: Mapped[str] = mapped_column(String(255))
+    revised_headline: Mapped[str] = mapped_column(String(255))
+
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow)
+
+
+class RankingLog(Base):
+    __tablename__ = "ranking_logs"
+    __table_args__ = (
+        Index("idx_event_time", "event_id", "observed_at"),
+    )
+
+    id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
+    event_id: Mapped[int] = mapped_column(ForeignKey("trending_events.id"))
+    ranking_position: Mapped[int] = mapped_column(Integer)
+    observed_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow)
+
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow)
+
+
+# ==========================================
+# 模块五：多态话题与多态评论
+# ==========================================
+class ExtractedTopic(Base):
+    __tablename__ = "extracted_topics"
+    __table_args__ = (
+        Index("idx_topic_keyword", "topic_keyword"),
+        Index("idx_polymorphic_topics", "target_type", "target_id"),
+    )
+
+    id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
+    target_type: Mapped[TargetType] = mapped_column(Enum(TargetType))
+    target_id: Mapped[int] = mapped_column(BigInteger)
+    topic_keyword: Mapped[str] = mapped_column(String(100))
+    relevance_score: Mapped[Optional[float]] = mapped_column(Float)
+
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow)
+
+
+class DiscussionComment(Base):
+    __tablename__ = "discussion_comments"
+    __table_args__ = (
+        Index("idx_polymorphic_comments", "target_type", "target_id"),
+    )
+
+    id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
+    target_type: Mapped[TargetType] = mapped_column(Enum(TargetType))
+    target_id: Mapped[int] = mapped_column(BigInteger)
+
+    commenter_name: Mapped[Optional[str]] = mapped_column(String(100))
+    comment_content: Mapped[str] = mapped_column(Text)
+    likes_count: Mapped[int] = mapped_column(Integer, default=0)
+    external_comment_id: Mapped[Optional[str]] = mapped_column(String(32))
+    comment_time: Mapped[Optional[datetime]] = mapped_column(DateTime(timezone=True))
+
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow)
+
+
+# ==========================================
+# 模块六：用户画像与多渠道高可用推送系统
+# ==========================================
+class AppUser(Base):
+    __tablename__ = "app_users"
+
+    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
+    email: Mapped[str] = mapped_column(String(150), unique=True, index=True)
+    password_hash: Mapped[Optional[str]] = mapped_column(String(255))
+
+    nickname: Mapped[Optional[str]] = mapped_column(String(100))
+    avatar_url: Mapped[Optional[str]] = mapped_column(String(500))
+    gender: Mapped[GenderType] = mapped_column(Enum(GenderType), default=GenderType.UNKNOWN)
+
+    # 核心：万能扩展收纳箱 (SQLite 完美支持通过 SQLAlchemy 存储 JSON)
+    metadata_: Mapped[Optional[Any]] = mapped_column("metadata", JSON, comment="自定义扩展偏好")
+
+    timezone: Mapped[str] = mapped_column(String(50), default="Asia/Shanghai")
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow)
+    updated_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow, onupdate=utcnow)
+
+
+class UserPushEndpoint(Base):
+    __tablename__ = "user_push_endpoints"
+    __table_args__ = (
+        UniqueConstraint("user_id", "channel_type", name="idx_unique_user_channel"),
+    )
+
+    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
+    user_id: Mapped[int] = mapped_column(ForeignKey("app_users.id"))
+    channel_type: Mapped[str] = mapped_column(String(50), comment="如 EMAIL, WECHAT")
+    channel_account: Mapped[str] = mapped_column(String(255))
+    is_active: Mapped[bool] = mapped_column(Boolean, default=True)
+    priority_level: Mapped[int] = mapped_column(Integer, default=1, comment="1最高，降级重试")
+
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow)
+    updated_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow, onupdate=utcnow)
+
+
+class UserTopicPreference(Base):
+    __tablename__ = "user_topic_preferences"
+    __table_args__ = (
+        UniqueConstraint("user_id", "interested_keyword", name="idx_unique_preference"),
+    )
+
+    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
+    user_id: Mapped[int] = mapped_column(ForeignKey("app_users.id"))
+    interested_keyword: Mapped[str] = mapped_column(String(100))
+
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow)
+
+
+class UserDeliverySchedule(Base):
+    __tablename__ = "user_delivery_schedules"
+    __table_args__ = (
+        UniqueConstraint("user_id", "delivery_time", name="idx_unique_schedule"),
+    )
+
+    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
+    user_id: Mapped[int] = mapped_column(ForeignKey("app_users.id"))
+    delivery_time: Mapped[time] = mapped_column(Time, comment="如 08:30:00")
+    is_active: Mapped[bool] = mapped_column(Boolean, default=True)
+
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow)
+
+
+class DeliveryHistory(Base):
+    __tablename__ = "delivery_history"
+    __table_args__ = (
+        UniqueConstraint("user_id", "target_type", "target_id", name="idx_prevent_duplicate_push"),
+    )
+
+    id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
+    user_id: Mapped[int] = mapped_column(ForeignKey("app_users.id"))
+    target_type: Mapped[TargetType] = mapped_column(Enum(TargetType))
+    target_id: Mapped[int] = mapped_column(BigInteger)
+    status: Mapped[TaskStatus] = mapped_column(Enum(TaskStatus))
+
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow)
+
+
+# ==========================================
+# 模块七：系统任务监控
+# ==========================================
+class DataSyncTask(Base):
+    __tablename__ = "data_sync_tasks"
+
+    id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
+    source_id: Mapped[int] = mapped_column(ForeignKey("info_sources.id"))
+    items_fetched: Mapped[int] = mapped_column(Integer, default=0)
+    task_status: Mapped[TaskStatus] = mapped_column(Enum(TaskStatus))
+    error_trace: Mapped[Optional[str]] = mapped_column(Text)
+
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow)
diff --git a/backend/app/schemas/__init__.py b/backend/app/schemas/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/backend/app/services/__init__.py b/backend/app/services/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/backend/app/tasks/__init__.py b/backend/app/tasks/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/backend/data/demo.db b/backend/data/demo.db
new file mode 100644
index 0000000..8711511
Binary files /dev/null and b/backend/data/demo.db differ
diff --git a/backend/run.py b/backend/run.py
new file mode 100644
index 0000000..b22127e
--- /dev/null
+++ b/backend/run.py
@@ -0,0 +1,12 @@
+# run.py
+import uvicorn
+
+if __name__ == "__main__":
+    # 调用 uvicorn.run() 启动服务
+    uvicorn.run(
+        app="app.main:app",
+        host="0.0.0.0",
+        port=8000,
+        reload=True,
+        workers=1
+    )
diff --git a/backend/test.py b/backend/test.py
new file mode 100644
index 0000000..24432c9
--- /dev/null
+++ b/backend/test.py
@@ -0,0 +1,23 @@
+import os
+
+def print_tree(root, prefix=""):
+    items = sorted(
+        name for name in os.listdir(root)
+        if name != "__pycache__"
+    )
+    total = len(items)
+
+    for i, name in enumerate(items):
+        path = os.path.join(root, name)
+        is_last = (i == total - 1)
+
+        connector = "└── " if is_last else "├── "
+        print(prefix + connector + name)
+
+        if os.path.isdir(path):
+            extension = "    " if is_last else "│   "
+            print_tree(path, prefix + extension)
+
+root_dir = r"E:\ScnuProject\InsightRadar\backend\app"   # 改成你的目录
+print(os.path.basename(root_dir) + "/")
+print_tree(root_dir)
\ No newline at end of file
diff --git a/backend/test_main.http b/backend/test_main.http
new file mode 100644
index 0000000..a2d81a9
--- /dev/null
+++ b/backend/test_main.http
@@ -0,0 +1,11 @@
+# Test your FastAPI endpoints
+
+GET http://127.0.0.1:8000/
+Accept: application/json
+
+###
+
+GET http://127.0.0.1:8000/hello/User
+Accept: application/json
+
+###