That's pretty much a production problem. It's somewhat common to see "warmup" scripts that make sure all the VMs start.
The OP was talking about development time.
The issue is actually that it takes time to load the application code and dependencies, something that applies to Django, Rails and just about any similar framework, regardless of whether it's the production or development environment. In general, the production environment will actually be faster at this.
Just to clarify the context to future readers, I deleted by post because I wasn't interested in discussing django, but since you responded I'm addressing it. My original post pointed out that in my experience it indeed does take time to load django and linked to this post: http://stackoverflow.com/questions/1702562/speeding-up-the-f...