Development, production parity

The development, production parity principle states the importance of keeping the development and production environments as identical as possible. For example, let's consider an application with multiple services or processes, such as a job scheduler service, cache services, or one or more application services. In a development environment, we tend to run all of them on a single machine. Whereas, in production, we will facilitate independent machines to run each of these processes. This is primarily to manage cost of the infrastructure. The downside is that, if production fails, there is no identical environment to reproduce and fix the issues.

This principle is not only valid for microservices, but it is also applicable to any application development.