build optimisation

backend/Dockerfile

@@ -4,14 +4,15 @@ FROM python:3.12-slim
 # Set the working directory in the container
 WORKDIR /usr/src/app
 
+# Install any needed packages specified in requirements.txt
+COPY requirements.txt requirements.txt
+RUN pip install --upgrade pip
+RUN pip install --no-cache-dir --upgrade -r requirements.txt
+
 # Copy the current directory contents into the container at /usr/src/app
 COPY . .
 COPY .env.docker-compose.template .env
 
-# Install any needed packages specified in requirements.txt
-RUN pip install --upgrade pip
-RUN pip install --no-cache-dir -r requirements.txt
-
 # Make port 80 available to the world outside this container
 EXPOSE 80