# Application Startup Configuration
When the application starts up, we often need to set up some initialization logic. The application bootstraps with those specific configurations. It is in a healthy state and be able to take external service requests after those configurations successfully applied. Otherwise, it failed.
The framework starts with a file called
app.js that executes the application initialization logic, if present, and it returns a function.
For example, we need to load a list of national cities from the remote server during application startup for subsequent use in the controller:
cities attribute has attached on the global
app. It can be accessed in the controller,
Note: When the framework executes the lifecycle method
beforeStart, do not run time-consuming operation. The framework enables a Timeout setting by default when it starts up.