diff --git a/backend/auth/Dockerfile b/backend/auth/Dockerfile
index bb1c6d0..a785d62 100644
--- a/backend/auth/Dockerfile
+++ b/backend/auth/Dockerfile
@@ -2,13 +2,16 @@ FROM python:3.13-slim
 
 WORKDIR /home/booksystem/auth
 
+# 先复制依赖文件并安装，充分利用 Docker 构建缓存
 COPY requirements.txt .
 RUN pip install --no-cache-dir -r requirements.txt -i https://mirrors.aliyun.com/pypi/simple/
 
-COPY . .
-
+# 复制 swagger-ui 静态文件（不常变化）
 COPY swagger-ui /home/booksystem/swagger-ui
 
+# 最后复制应用代码（经常变化）
+COPY . .
+
 EXPOSE 8000
 
-CMD ["python", "main.py"]
+CMD ["python", "main.py"]
\ No newline at end of file