CI/CD (Continuous Integration/Continuous Delivery) is a software development methodology that ensures reliability and speed of product creation. It belongs to one of the typical DevOps practices.

Its main difference is that the testing and assembly of the code is carried out automatically. This approach avoids mistakes in the early stages and minimizes risks.

Principles of operation

CI (Continuous Integration) — continuous integration. While writing the code, developers constantly make changes that are uploaded to the repository. For automatic testing and verification, specialized services are used, for example, Github, which create scripts. A log is kept for each step, which records any changes.

CD (Continuous Delivery) — continuous delivery. Responsible for the automatic deployment of the build in any environment: production, testing or development environment. For example, after editing the code, it is automatically placed in the testing area.

The methodology is used in companies that often modify code during development, but at the same time release stable releases. Developers receive an automatic application testing and deployment process, which allows them to focus on continuous software improvement.

Stages of the methodology

The CI/CD cycle is conventionally divided into 7 stages:

1. Creation. Programmers write a certain part of the code, and then test it manually. If the test is successful, the parts are combined into a single code and transferred to the development work branch.
2. Assembling. At the second stage, special software is used to control the version of the product, for example, Git. The program starts an automatic build with the changes made, and then the resulting code is tested. The criteria for successful completion are configured manually.
3. A manual test. After passing the autotest in the software, the product is sent to the test team for verification. They manually check the written code and look for bugs.
4. Release. After the successful completion of the third stage, the code is released. A working build is being created to update the current software product to the current version.
5. Deployment. The received update is broadcast on the official developer servers to update the software to the latest version.
6. Support and monitoring. Programmers track consumer feedback and prepare a list of future changes.
7. Planning. At the last stage, an approved list of changes is created for the next versions. At the end of this step, the development cycle ends and begins anew.

With this principle of operation, users receive a fully working release. If they find an error or bug, they report it to tech support.

The CI/CD methodology reduces software development time, identifies errors and flaws in the early stages of code creation, and reduces recovery time in the event of an incident.

Changes are logged, which speeds up the process of tracking errors and adding new features to the software product.