Continuous Integration

Continuous Integration (CI)

In today's rapidly advancing and highly competitive global IT industry, agility, quality, and time to market have become the key contributors to software' overall success. Whether an organization is delivering a new product or rolling out new features of existing software, there is tremendous pressure to rapidly produce and deliver while keeping up with the customer demands and ensuring consistent business growth. While organizations cannot guarantee the success of a software product, they can certainly adopt methodologies and practices that drastically increase the probability of a product's success and ensure its popularity among users.

Continuous Integration is one such practice that helps improve the efficiency of software development workflow and streamlines it to be more manageable, comprehensive, agile, secure, and reliable.

In this article, we delve into the concept of Continuous Integration to elucidate its importance and comprehend how it streamlines software development workflows, making it highly beneficial for organizations.

What is Continuous Integration (CI)?

A software engineering practice, Continuous Integration (CI), requires developers to integrate source code changes regularly into a shared code repository, several times a day. Automated testing is done against each iteration of the build to identify and assert the new code’s correctness before integration. This helps avoid issues at the final integration stage, before the release, and allows the team to deliver higher quality software with more predictable delivery schedules.

Moreover, it enables application development teams to release incremental code changes to the production environment, quickly and regularly leveraging the capabilities like frequent code commit, comprehensive monitoring, observability, etc., which allows early and automated detection of issues, visibility, and fast feedback.

Continuous integration, in short, is a continuous provision of all the elements required for a successful new release, for which it follows an automated process that ensures secure and frequent integration of the source code into the source baselines.

Continuous Integration In DevOps:

Continuous Integration is an essential aspect of DevOps and the first stage of the three-phased automated software release pipeline of DevOps- Continuous Integration, Continuous Deployment, and Continuous Delivery. It is implemented first in the DevOps development cycle, as it helps build the entire workflow and serves as a prerequisite for continuous delivery stages of software testing, deployment, and release.

The main objective of Continuous Integration is to prevent integration problems by bringing developers together and merging their source code changes into a central repository, where automated builds and tests are executed. This helps the team to find and address issues faster, improve software quality, and reduce the validation time while enabling better transparency and insight into the software development and delivery process and ensuring the seamless release of new software updates.

Why Continuous Integration?

From facilitating collaboration among team members to enabling them to create more dependable code, the reasons for implementing continuous integration during the software development lifecycle are numerous, a few of which are listed below:

  • Helps boost code test coverage.
  • Allows easier and faster detection of bugs.
  • Helps teams to build repeatable processes.
  • Prevents breaks and issues in builds and code.
  • Helps build DevOps and Agile workflows.
  • Automates the process of code deployment to the production environment.
  • It helps run simultaneous procedures, which saves time and effort.
  • Decreases code review time by enabling early detection of bugs and discrepancies.
  • Allows teams to execute code testing in the real world, facilitating better quality, performance, and reliability.
  • Activates build and compilation processes freeing team members to focus on other tasks.

Prerequisites of Continuous Integration:

For a successful implementation of Continuous Integration into the existing software development workflow, organizations must ensure the development teams consider the CI prerequisites, as these ensure the accuracy of the process and help the team be more productive. Moreover, these prerequisites are the pillars of continuous integration and help increase focus, identify and remove bottlenecks, reduce resource utilization, and enable the team to deliver new software updates to users faster and more frequently.

Hence, the prerequisites of Continuous Integration are:

  • Version Control: Also known as the source code management system, Version Control is a reliable method for centralizing and preserving changes made in the source code over time so that when the code is modified the team can still access the previous revisions. It is an effective way of communicating and resolving editing conflicts between multiple developers working on the same codebase. This is enabled by a variety of tools like Git and Subversion.
  • Virtual Machines: Another critical requirement of Continuous Integration is to have a spare server or virtual machine when building your system. This prevents issues and delays in validating each integration and code change and makes the process more streamlined.
  • Hosted CI Tool Solutions: Apart from virtual machines and servers, teams can also opt for hosted CI tool solutions, as they help maintain the whole process and ensure its scalability.
  • Automated Tools: From build to testing, Continuous Integration relies on automation for a variety of functions. Hence you will have to install a suitable CI tool like Jenkins, TeamCity, Bamboo, GitLab, etc. for continuous, consistent, and quality integration and delivery.

Now that we know the basic requirements of Continuous Integration, let us move on to understanding how CI works.

Continuous Integration Workflow:

Once the prerequisites are in place, the team works on implementing the CI workflow, which involves the following steps:

  • Code & Change Input: In the first step of CI workflow, developers input code into their private workspaces. After which, the changes are committed to the shared repository.
  • Monitor & Analyze Changes: Once the changes are committed, the CI server monitors the repository and analyzes the changes as they occur.
  • Build & Test: The CI then builds the system and executes automated unit and integration tests to identify issues and bugs in the code. Here, the server also releases deployable artifacts for testing.
  • Assign & Report: A build tag is assigned to the version of the code just built by the CI server, which also provides the team reports of the successful build. If the build or tests fail, the server alerts the development team.
  • Defect Rectification: Finally, reported discrepancies are fixed by the team as soon as possible.

Continuous integration continues to integrate and run tests throughout the entire project, to further validate changes and ensure the frequent and rapid release of software/software updates.

Continuous Integration Best Practices:

The process of Continuous Integration in the DevOps software development pipeline can be further enhanced by adopting CI best practices that enhance its accuracy, facilitate transparency, and allows the team to save time on build and testing. These best practices are:

  • Maintain a code repository.
  • Automate Build and Deployment.
  • Enable build self-testing.
  • Regularly commit to the baseline every day.
  • Ensure every commit to baseline should be built.
  • Every bug-fix commit should be fixed immediately and must come with a test case.
  • Keep the build fast with automated deployment.
  • Perform regular and early check-in.
  • Build and test everything after every minute change.
  • Maintain stronger source code control.
  • Don't rely on an integrated development environment (IDE).
  • Act on metrics and data.
  • Ensure it is easy for everyone to get the latest deliverables.
  • Make sure everyone has access to see the latest build results.
  • Use a clone of the production environment for testing.

Advantages of Continuous Integration:

Used alongside agile software development workflow, Continuous Integration is a valuable and well-established practice that significantly reduces integration problems and allows the team to develop cohesive software more rapidly. It offers various benefits to the development team, product managers, and the overall organization, enabling them to better plan and execute their marketing strategies.

Other prominent advantages of CI include:

  • Improves developer productivity by automating tasks, enabling them to deliver more value to customers.
  • Allows early and improved error detection and rapid resolution.
  • Increases efficiency, reduces integration risks and breaks and enhances services agility.
  • Helps deliver updates and features faster and more frequently.
  • Improves team collaboration and enhances communication.
  • Improves system integration and feedback loop.
  • Facilitates transparency and visibility.
  • Improves quality and testability.
  • Enables developers to develop functional and quality code.
  • Enables better transparency and insight into the software development delivery process.

Disadvantages of Continuous Integration:

The benefits of Continuous integration though outweigh the disadvantages it offers, it is still important for us to be aware of them as they can impact the entire DevOps release cycle. Therefore, the following are some of the common disadvantages of Continuous Integration:

  • Requires initial setup time and CI server training.
  • Constructing automated test suites requires a considerable amount of work.
  • Requires additional servers and environments.
  • It is essential to develop suitable test procedures.
  • Delay may occur during code integration if multiple developers integrate their code simultaneously.

Continuous integration Vs. Continuous Delivery Vs. Continuous Deployment:

Continuous Integration, Continuous Delivery, and Continuous Deployment are three closely related concepts of DevOps that are focused on different aspects of software development and delivery processes.

Continuous Integration ensures code quality through automated tests before each code integration, whereas Continuous delivery is focused on continuously delivering integrated code to the test or production environment. The only common aspect between these two is that they require manual intervention. Continuous deployment goes one step further from the delivery phase and allows the team to automatically deploy changes that have passed the continuous integration, to the production without any human intervention.

Tools for Continuous Integration (CI):

A prominent reason for the popularity of Continuous Integration is that it automates build and test execution, which prevents manual efforts and allows the team to focus on other critical tasks. However, currently, there is a wide range of CI tools available, choosing the suitable one from which can be extremely tedious.

Therefore, here is a list of some of the most popular continuous integration tools for you to choose from:

  • Buddy: The most powerful, smart, and easy-to-configure CI/CD tool, Buddy is web-based and self-hosted continuous integration and delivery software designed to lower the entry threshold to DevOps. It is used for projects that use code from the Bitbucket and GitHub repositories. Buddy is a commercial tool with a user-friendly interface, minimalistic material design, Docker support, etc.
  • Jenkins: A free, open-source continuous integration tool, written using Java, Jenkins is a server-based CI application that requires a web server to operate on. It is a widely used tool that allows developers to build, integrate, and test code automatically, immediately after they are committed to the source repository. It helps developers to easily identify bugs early in the lifecycle and deploy software/updates faster.
  • TeamCity: A powerful and intelligent commercial CI server from JetBrains, TeamCity uses automatic framework and configuration to perform code coverage, code analysis, avoid code duplication, etc. It is an easy-to-install tool, with a user-friendly interface and quality features like comprehensive VCS integration, on-the-fly build progress reporting, and more.
  • Bamboo: A server-based CI and deployment tool from Atlassian, Bamboo is a popular choice for automating software release management. It works seamlessly with JIRA software and Bitbucket and supports various languages and technologies like CodeDeploy, Ducker, Git, AWS, Amazon S3 buckets, etc.
  • GoCD: An open-source continuous integration server, used for modeling and visualizing complex workflows with ease, GoCD allows continuous delivery and provides an intuitive interface for building CD pipelines. It supports parallel and sequential execution and can easily configure dependencies. Moreover, with this tool developers can deploy to production securely.
  • GitLab CI: Another free, open-source continuous integration tool, GitLab CI is highly scalable, easy to install and setup, and provides a friendly user interface. Designed to improve Github’s overall experience, this tool offers a modern UX with container support and various other beneficial features.
  • Circle CI: Circle CI is a flexible continuous integration and delivery platform that can run in any environment and supports multiple coding languages, version control systems, container systems, and delivery mechanisms. This tool helps reduce bugs, improves software quality, and can be hosted on-premise or used through a cloud offering.
  • Codeship: A powerful CI tool, Codeship automates the development and deployment workflow and provides full control over system design, its customization, and optimization. It is a Software as a Services that helps teams to implement and optimize CI and CD in the Cloud and develop applications to achieve fast, secure, and frequent code delivery.


Continuous Integration has become the need of the hour for modern and high-performing organizations that want to better cater to their more informed and tech-savvy customer base with low-risk and rapid releases. It is one effective software development and delivery strategy that streamlines SDLC and allows businesses to quickly adapt to changing business and user requirements.

In short, by adopting Continuous Integration organizations not only improve their development model by reducing risks and catching bugs quickly but also ensure rapid delivery of enterprise-grade software.