Everybody is talking about cloud-native. Infrastructure is moving to the cloud. In the meantime, non-technical staff fails to realize that code that fulfills functional requirements is a small fraction of the final delivery.
There is an impedance mismatch between business and information technology professionals on what is a software delivery.
This impedance mismatch can only be reduced by tearing down the walls that separate business and development team. This is a movement that started with Agile and XP (eXtreme Programming) but this a road that must be further explored. The communication must go beyond meetings, hybrid teams should have working sessions together, for instance, business people doing pair-programming with developers.
This article presents a bird view of what makes a cloud-native project, a description of its constituents, and why their presence is mandatory.
Fictitious software project
In this article I will use the following scenario: recently, a fictitious company decided to move to GCP (Google Cloud Platform) and adopted a cloud-native approach. The main development language is Python.
Cloud-native requires the extensive use of cloud provider serverless offerings and managed services. Everything must be automated, i.e., there is no space for manual deployments, environment or infrastructure commands, and any other non-repeatable and scripted actions. In fact, nothing can be done using graphical user interfaces.
A new project has been launched and a set of functional requirements were passed to the development team. Functional requirements are product features or functions that developers must implement to enable users to accomplish their tasks. Naturally, functional requirements will be fulfilled in Python code.
Multiple levels of code
Now I want to give you the shocking news: the Python code that directly responds to the project requirements is just 10 to 20% of the final codebase!
In this article, I will explain what the development team will be doing and the software layers present in a modern cloud-native project.
Application code is the Python and SQL code that responds to functional requirements. This is the code everybody is expecting from the beginning. No surprises here.
Unit test are also developed in Python. Usually there are more lines of unit test code than application code, sometimes 2 or 3 times more.
Test coverage is highly debated in the development community. About code coverage I just want to say that 100% is not desirable, a very good and realistic coverage is 70%.
Continuous Integration (CI)
CI/CD are the most defining engineering practices in cloud-native development. The only realistic way to have consistent development and deployment practices is with full automation. CI/CD is the automation of every tasks that support testing, integration and deployment in every relevant environment.
Continuous Delivery (CD)
Continuous Deployment (CD)
Infrastructure as Code (IaC)