What Is CI/CD In Software Engineering?

CI/CD, known as Continuous Integration and Continuous Delivery, are concepts within Agile software development, particularly in the DevOps framework. They embody principles and best practices that streamline the process of swiftly, efficiently, and reliably delivering code changes. Put it simply:

• Continuous Integration (CI): It makes sure that different changes to the code are constantly combined and tested to prevent conflicts.
• Continuous Delivery/Deployment (CD): This part automatically takes your finished app (and its infrastructure blueprints) and deploys them as you planned.

In this blog, we’ll explore the significance of CI/CD in software development and highlight how DevOps teams can automate the entire process from integration to delivery along the CI/CD pipeline. 

What is Continuous Integration (CI)

CI(Continuous Integration) is a DevOps practice that automatically builds, tests, and merges every code change in a shared repository. By validating each commit in real time, CI catches bugs early, keeps all platforms in sync, and speeds up the delivery of reliable software.

Through CI, developers integrate the new code they’ve written regularly throughout the software development cycle, adding it to the Codebase at least once.

Within agile methodologies, Continuous Integration (CI) simplifies the resolution of issues found between newly written and old code, enabling quick bug solutions. 

This automated approach to software development promotes quick iterations of the product by eliminating manual errors and creating standardized feedback loops for software engineers.

What is Continuous Delivery (CD)

Continuous delivery is a step in the CI/CD pipeline that picks up where continuous integration ends. It automatically delivers applications or verified code updates to designated environments, including production, development, and testing environments. 

The operations team can modify a live production environment within the continuous delivery workflow. Here, the software and APIs are effectively tested, and all errors are resolved through an automated process. 

In general, the continuous delivery phase in the CI/CD pipeline aims to release new code as quickly as possible while retaining some degree of human control.

Continuous Deployment vs Continuous Delivery: Key Differences

Continuous Deployment and Continuous Delivery are two code deployment strategies pivotal to automation in software development. Their differences mainly lie in the degree of automation for software or app releases. To put it simply, Continuous Delivery prepares each change for release; Continuous Deployment actually ships it. Here’s a table of comparison to understand better the difference between the two:

	Continuous Delivery	Continuous Deployment
What are they?	Development teams usually have many environments to stage application updates for testing and review. Continuous delivery is the automation mechanism that sends apps to one or more delivery environments.	Continuous deployment is an extension of continuous delivery that enables the software to be released after each code commit passes a test.
Deployment Automation	After builds, unit, and integration testing are automated in continuous integration (CI), continuous delivery automates the deployment of verified code. This implies that when a developer updates an application, it is immediately tested for bugs and published to a repository, where the operations team may deploy it to a live production environment.	Developer changes are automatically released from the repository to production, where users can access them. If changes to a cloud application pass automated testing, it should be ready for use within minutes of writing.
Direct-to-Production	After successful testing, human assistance is typically required in continuous delivery before moving to the production phase. So, to facilitate an efficient continuous delivery process, you need continuous integration (CI) as part of your development pipeline.	When code passes testing on CD, it is automatically deployed to production without human approval. Continuous deployment addresses the issue of operations teams being overburdened with manual procedures that impede app delivery. Automating the subsequent pipeline stage expands on the advantages of continuous delivery.

When combined, the two reduce the risk associated with app deployment, making it easier to distribute updates to apps gradually rather than all at once.  

Continuous delivery can resolve the issue of poor visibility and communication between DevOps and business teams. Its goal is to guarantee that new code can be deployed with the least amount of work possible. 

Similarly, continuous delivery ensures the Codebase is always ready for deployment to a production environment.

On the other hand, Continuous deployment eliminates human intervention against untested code in running software. However, it requires upfront investment because automated tests must be created to support a range of testing and release phases in the CI/CD pipeline.

CI vs CD (Delivery) vs CD (Deployment)

These three approaches represent different levels of automation in software development, each serving distinct business purposes. Continuous Integration (CI) focuses on keeping your development process smooth by automatically testing code changes as developers work, helping catch problems before they become expensive fixes.

Continuous Delivery takes this further by ensuring your software is always ready to deploy, but leaves the final release decision in human hands. This gives you control over timing—you can coordinate releases with marketing campaigns, avoid busy periods, or wait for additional testing.

Continuous Deployment removes human decision-making from the release process entirely. Once code passes all automated tests, it goes live immediately. This maximizes speed and keeps your software constantly updated, but requires exceptional confidence in your automated testing and monitoring systems.

The key difference between CD, deployment, and CI lies in control versus speed. CI gives you quality assurance, Continuous Delivery gives you deployment readiness with release control, and Continuous Deployment gives you maximum velocity with full automation. Your choice depends on your industry, risk tolerance, and how quickly you need to respond to user needs or market changes.

Difference	Continuous Integration (CI)	Continuous Delivery (CD)	Continuous Deployment (CD)
Definition	Frequently merging developer code into a shared repository.	Ensuring code is always ready and tested for deployment.	Automatically deploying every validated change to production.
Main Goal	Early detection of integration bugs.	Keeping software deployable at any time.	Reducing time-to-market through automatic production deployments.
Trigger	Code commits to the main repository.	Code successfully passes integration and acceptance tests.	All tests passing triggers automatic deployment.
Automation Level	Automated builds, tests, and reporting.	Automated testing, build packaging, and release-ready state.	Fully automated pipeline from code commit to production deployment.
Human Intervention	Developers manually merge code; manual checks possible.	Manual approval required before deploying to production.	No manual approvals; fully automated deployment to production.
Frequency	Several times per day.	Potentially frequent; manual decision controls final deployment frequency.	Multiple deployments daily; each valid change deploys immediately.
Risk & Control	Lower risk, high control.	Moderate risk; control via manual release decision.	Higher risk; minimized through rigorous automated testing.
Typical Tools	Jenkins, GitHub Actions, GitLab CI, CircleCI	Jenkins, Spinnaker, GitLab CI/CD, ArgoCD	Spinnaker, Jenkins, ArgoCD, GitLab CI/CD
Business Impact	Faster bug detection, improved code quality.	Shorter release cycles, reliable software availability.	Fastest release cycles, rapid innovation, and customer responsiveness.

CI/CD Pipeline Stages

A well-designed pipeline balances speed with safety—automating repetitive tasks while maintaining human oversight where it matters most. The stages work together like a factory assembly line, where each step validates the previous work and prepares for the next. When one stage fails, the entire pipeline stops, preventing flawed code from advancing further.

This fail-fast approach saves time, reduces risk, and ensures that only thoroughly tested, approved changes reach your users. Whether you’re building a simple web application or a complex distributed system, these core stages provide the foundation for reliable, continuous software delivery:

Stage 1: Code Commit & Version Control

The pipeline begins when developers push code changes to a version control system like Git. This stage establishes the foundation for all subsequent automation.

What happens:

• Developer commits code changes to a branch
• Version control system (Git, SVN) records the change
• Webhook or polling mechanism triggers the pipeline
• Code is tagged with version information and metadata

Common tools: Git, GitHub, GitLab, Bitbucket, Azure Repos

Stage 2: Build & Artifact Packaging

Once code is committed, the build stage compiles source code into executable artifacts and packages them for distribution.

What happens:

• Source code is compiled into binaries or bytecode
• Dependencies are resolved and included
• Configuration files are processed
• Artifacts are packaged (JAR, Docker images, executables)
• Build metadata and version numbers are applied

Common tools: Maven, Gradle, npm, Docker, Jenkins, GitHub Actions

Stage 3: Unit / Integration Tests

Testing ensures code quality and functionality before deployment. This stage runs various types of automated tests to catch bugs and regressions.

What happens:

• Unit tests verify individual components work correctly
• Integration tests check that different parts work together
• Code coverage analysis measures test completeness
• Static code analysis identifies potential issues
• Security scans check for vulnerabilities

Common tools: JUnit, pytest, Jest, SonarQube, Selenium, Cypress

Stage 4: Deploy to Staging

The staging environment mimics production as closely as possible, allowing for final validation before live deployment.

What happens:

• Application is deployed to a production-like environment
• Database migrations are executed if needed
• Configuration is applied for the staging environment
• Health checks verify the deployment was successful
• End-to-end tests may run in this environment

Common tools: Kubernetes, Docker Swarm, AWS ECS, Ansible, Terraform

Stage 5: Manual Approval / Gates

Before production deployment, many organizations require human approval to ensure control over what goes live.

What happens:

• Pipeline pauses and waits for human intervention
• Designated approvers review changes and test results
• Business stakeholders may validate functionality
• Risk assessment is performed for the deployment
• Approval is granted or deployment is rejected

Common tools: GitHub PRs, GitLab merge requests, Jira, ServiceNow, custom approval workflows

Stage 6: Deploy to Production & Rollback

The final stage deploys the application to the live production environment where end users can access it.

What happens:

• Application is deployed to production servers
• Traffic is gradually shifted to the new version (blue-green, canary)
• Monitoring systems track application health and performance
• Alerts are configured to notify teams of issues
• Rollback procedures are ready if problems occur

Common tools: Kubernetes, AWS ECS, Azure Container Instances, Load Balancers, Istio, Envoy

Popular CI/CD Pipeline Tools in 2025

CI/CD tools are becoming more and more intelligent and focused. They are no longer just about running automated tests and deployments. They are starting to incorporate AI capabilities, better integrate with the cloud infrastructure, and simplify complex workflows so that other employees can take control over processes.

Jenkins – The veteran that’s still powerful but showing its age

• Best for: Complex, highly customized projects that need maximum flexibility
• Reality check: High maintenance overhead, requires dedicated specialists
• When to choose: You have unique requirements that off-the-shelf tools can’t handle

GitHub Actions – The crowd favorite for good reason

• Best for: Teams already using GitHub who want simple, fast setup
• Why it works: Everything in one place – no switching between tools
• When to choose: You’re a small to medium team prioritizing developer experience

GitLab CI/CD – The enterprise all-in-one solution

• Best for: Large organizations needing security, compliance, and governance
• Trade-off: More expensive but includes everything from planning to monitoring
• When to choose: You need enterprise-grade features and unified toolchain

CircleCI – The speed demon with smart pricing

• Best for: Teams obsessed with fast builds and performance optimization
• Unique angle: Pay-per-use credits encourage efficient pipeline design
• When to choose: Build speed directly impacts your business velocity

Azure Pipelines – Microsoft’s ecosystem play

• Best for: Organizations already invested in Microsoft/Azure infrastructure
• 2025 focus: Heavy AI integration and security automation
• When to choose: You’re in the Microsoft ecosystem and want deep integration

AWS CodePipeline – Amazon’s cloud-native approach

• Best for: AWS-heavy organizations wanting seamless cloud integration
• Pricing shift: Moving to per-minute billing encourages lean, efficient pipelines
• When to choose: Your infrastructure lives primarily in AWS

Spacelift – The infrastructure specialist

• Best for: Teams managing complex Infrastructure as Code (IaC) deployments
• Standout feature: AI-powered troubleshooting specifically for infrastructure issues
• When to choose: Infrastructure management is a major pain point for your team

CI Advantages

A continuous integration (CI) pipeline yields more benefits than simply increasing the efficiency of an already-existing operation. The advantages of CI are:

1. Early Bug Detection

CI ensures that code release procedures are standardized across all projects along the CI/CD pipelines. It also facilitates additional testing in test environments before finally sending the code to production. The end product is a more stable codebase with fewer defects.

2. Improved Software Quality 

Continuous integration (CI) is a reliable method for software engineers who want to write and test code. The deployment process along the CI pipeline is also standardized, resulting in high-quality software releases.

CD Advantages

Continuous Delivery offers many advantages to software development teams, such as process automation that guarantees:

1. Faster Release Rates

CD facilitates the DevOps team’s rapid and regular delivery of updates to clients. Implementing CI/CD increases the velocity of the team, including the deployment of code features and timely bug fixes.

2. Better User Feedback Loop

CD enables a better user feedback loop by releasing new features more quickly. The code deployment strategies in CD also allow you to test things and get feedback so you can determine what works and prioritize changes and enhancements.

Challenges in CI/CD Implementation and Where You Address Common Hurdles

Implementing a CI/CD pipeline comes with various challenges. Here’s a look at some of them and potential solutions to help you maximize the benefits of your CI/CD strategy:

Infrastructure Challenges

Scalability problems in CI/CD pipelines can result in significant delays if left unchecked. Sometimes, the pipeline’s infrastructure cannot shoulder the extra demands of your software projects with the expansion of the development team. 

To be on the safer side, the current CI/CD pipeline’s infrastructure must always support the additional load. One solution to this challenge is to leverage cloud-based services that automatically scale in response to demand.

Integration Challenges

Integration issues in CI/CD pipelines are frequent and can delay software development. For example, agile development requires quick and frequent testing cycles. However, it can be challenging to incorporate testing into the workflow effectively.

One potential solution is to leverage an agile testing tool that works well with your workflow and to automate testing to deliver quick feedback.

Conclusion

CI/CD forms the foundation of a DevOps methodology for building and deploying software. By incorporating the code deployment methodologies mentioned above into your continuous integration and deployment (CI/CD) workflow, your DevOps teams may release software more quickly while retaining higher quality and dependability.

Besides, automation in software development affords you the much-desired competitive edge, faster time-to-market, and enhanced customer satisfaction. It also ensures easy collaborations while using best practices of the best techniques and technologies in the industry.

If you’re looking to hire a DevOps engineer to help implement these practices, we can assist. Learn more about how our remote recruitment services can connect you with top DevOps talent tailored to your needs. 

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