Continuous integration and continuous development

Continuous integration(CI) and continuous development(CD) are integral aspects of Agile software methodology. Agile development is a much better alternative to all the traditional software management practices. Let us look at CI and CD in detail below.

Continuous integration

This is an agile software process where the developers are required to integrate the code into the main repository during various times of the day. This enables simultaneous updates and reduces the cost of integration by a huge margin. Unlike traditional cycle where the developers have to build the software in total isolation and integrate them only after developing all the modules, CI offers frequent integration during development.

The primary objectives of Continuous integration are

  • Reduce the cost of integration.
  • Discover conflicts and bug early and fix them.
  • Fast-tracking development process.

It is not easy to implement continuous integration manually and it requires a high level of automation. The automation includes robust testing and automated build.

Continuous development

This is a software process where continuous integration is followed by automated testing and automated daily deployment to the production. Any code change is automatically tested for quality and deployed. This ensures that a project is always market-ready. Everything from integration, quality testing, delivery, and deployment are automated for each iteration. Manual intervention is required only at the time of final push to the market.

The primary objectives of Continuous development are

  • Product is updated in real-time
  • It is always ready for market
  • Highest quality is maintained via robustly automated test suites

Continuous integration Key Concepts


One of the key concepts of CI is to encourage smaller updates. Developers are required to break complex work into micro modules and commit them as early as possible. Small changes are faster to develop and easy to integrate. When minor updates are integrated it also reduces the probability of errors which will reduce the cost of integration. Even when integrations problems arise, they are diagnosed early and fixed on a daily basis. Some of the significant techniques used are branch by abstraction and form-in progress code updates.

Trunk-Based Development

The idea behind Trunk-Based Development is to make sure that the development is always in the main branch or integrated back to the main branch in frequent intervals. In some cases, smaller branches are allowed provided they are small changes and integrated back to the main branch early. Except for the main branch, all other permissible branches are short lived. The main objective is to avoid larger changes which might result in errors. For the purpose of release, a dedicated release branch is allowed where no development takes place.

Also Read: Ways to secure Docker containers

Fast track Build and test

Each of the changes is handled by an automated build and test suites to ensure the highest quality is maintained throughout the project. As each and every minor change has to go through build and testing, it is important to automate and streamline the entire process. Increases in both build time and testing time should be considered with serious attention. Various tests can be run simultaneously to minimize testing time. Try to focus more on unit tests and integration testing for quality as they are faster to implement rather than acceptance testing.

Consistent Deployment

As each change undergoes the same pipeline of tasks like integration, build, testing, etc it is crucial to maintaining consistency throughout the deployment. There should be no change in the sequence of activities, the code should always be built first and should not be changed at any intervals after integration. Automation of building and testing should make use of the same tools and procedures for deploying all the changes.