A logical conclusion to enable reproducible environments is to make use of infrastructure as code (IaC). The idea is that all required steps, configuration, and versions are explicitly defined as code. These code definitions are directly used to configure the infrastructure. Infrastructure as code can be implemented in a procedural form, such as scripts, or in a declarative way. The latter approach specifies the desired target state and is executed using additional tooling. No matter which approach is preferred, the point is that the whole environment is specified as code, being executed in an automated, reliable, and reproducible way, always producing the same results.

In any way, the approach implies that the manual steps are kept to a minimum. The easiest form of infrastructure as code are shell scripts. The scripts should be executed from soup to nuts without human involvement. The same holds true for all IaC solutions.

Naturally the responsibility of installing and configuring environments moves from an operations team more toward developers. Since the development team sets certain requirements on the required runtime it makes sense for all engineering teams to work together. This is the idea behind the DevOps movement. In the past the mindset and method of operating too often was that application developers implemented software and literally passed the software and responsibilities toward operations - without further involvement on their side. Potential errors in production primarily concerned the operations team. This unfortunate process not only leads to tensions between engineering teams but ultimately lower quality. However, the overall goal should be to deliver high quality software that fulfills a purpose.

This goal requires the accountability of application developers. By defining all required infrastructure, configuration, and software as code, all engineering teams naturally move together. DevOps aims toward accountability of the software team as a whole. Infrastructure as code is a prerequisite which increases reproducibility, automation, and ultimately software quality.

In the topic Containers and Container orchestration frameworks, we will see how the presented technologies implement IaC.