To effectively design and build apps for the cloud, you should understand the twelve factors:
1 Codebase: One codebase tracked in revision control, many deployments
2 Dependencies: Explicitly declare and isolate dependencies
3. Config: Store configuration in the environment
4 Backing services: Treat backing services as attached resources
5 Build, release, run: Strictly separate build and run stages
6 Processes: Execute the app as one or more stateless processes
7 Port binding: Export services via port binding
8 Concurrency: Scale out via the process model
9 Disposability: Maximize robustness with fast startup and graceful shutdown
10 Dev/prod parity: Keep development, staging, and production as similar as possible
11 Logs: Treat logs as event streams
12 Admin processes: Run admin/management tasks as one-off processes
