12-Factor App

A methodology for building software-as-a-service apps.

Table of Contents

• I. Codebase: One codebase tracked in revision control, many deploys.
• II. Dependencies: Explicitly declare and isolate dependencies.
• III. Config: Store config in the environment.
• IV. Backing services: Treat backing services as attached resources.
• V. Build, release, run: Strictly separate build and run stages.
• VI. Processes: Execute the app as one or more stateless processes.
• VII. Port binding: Export services via port binding.
• VIII. Concurrency: Scale out via the process model.
• IX. Disposability: Maximize robustness with fast startup and graceful shutdown.
• X. Dev/prod parity: Keep development, staging, and production as similar as possible.
• XI. Logs: Treat logs as event streams.
• XII. Admin processes: Run admin/management tasks as one-off processes.