10. Minimizing Dev/prod parity

Keep development, staging, and production as similar as possible*

Continuous deployment allows to minimize the gap between development and production.

• A developer may write code which gets deployed in minutes/hours, and the developer who writes the code are closely involved in deploying it and watching its behavior in production.

There can be tool gap as well mostly because of different tools particularly the backing services being used in development and production.

For example, using SQLite locally and PostgreSQL in production; or local process memory for caching in development and Memcached in production.

• The twelve-factor developer resists the urge to use different backing services between development and production
• It might cause a code that worked and passed tests in development or staging to fail in production.
• Run local environments that closely approximate production environments.