Continuous integration (CI) and continuous deployment (CD) are software development lifecycle (SDLC) practices that automate integration, testing, and deployment of code. The CI/CD framework or pipeline helps developer, operations, and security teams efficiently deliver high-quality, high-performance, and secure applications. Implementing a CI/CD pipeline ensures users will have consistent access to the latest and most reliable software.
What is CI/CD?
Unlike a linear waterfall model, a CI/CD pipeline is an agile and iterative approach to software development that enhances collaboration, speeds up development and testing, and maintains a high-quality codebase.
During the CI stage of the pipeline, developers send code changes to a central repository. Each submission triggers an automated build and test process. This process can be iteratively repeated until the new code merges smoothly with the existing codebase.
At the other end of the pipeline, the CD stage automatically tests and validates code changes before releasing them into the production environment. These iterations ensure that new features, bug fixes, and improvements are delivered to users quickly and consistently.
Underlying both the CI and CD stages is a continuous delivery process. The goal of continuous delivery is to maintain code in an always-ready-to-deploy state. Continuous delivery uses internal staging environments to automatically test and validate code changes, ensuring code can be deployed at any time.
Why is CI/CD important?
The efficiency (or lack thereof) of a CI/CD pipeline can impact an organization’s software development and release cycles. Organizations that implement CI/CD best practices into their DevOps cycles can improve their release cycles, troubleshooting, team collaboration, and code quality, reliability, and security. Some key benefits include:
Accelerate time to market: CI/CD pipelines automate integration and deployment, shortening release cycles for new features and updates. This can help organizations respond quickly to user needs and market changes.
Shift-left testing: CI/CD integrates testing early in the software development workflow, identifying and resolving bugs sooner and at a small scale. This helps ensure end users work with a reliable software version, and it decreases the likelihood of users experiencing software issues.
IImprove DevSecOps collaboration: CI/CD practices improve collaboration across developer, operations, and security teams by providing a shared, continuously tested and updated code repository. This central repository—often referred to as the “single source of truth”—ensures that all teams collaborate more effectively, identify issues earlier, and deliver more secure, reliable software faster.
Ensure deployment success: CI/CD helps ensure code is always maintained in a deployable state by delivering smaller code changes to multiple environments more frequently. Code that is continuously tested, updated, and ready for release at any time helps streamline deployment to the production environment and reduces the risk of deployment failure or security breaches.
How does a CI/CD pipeline work?
A CI/CD pipeline consists of a series of automated tasks that streamline the software-development process and ensure code changes are continuously integrated, tested, validated, and deployed.
Many of the tasks in CI/CD are automated, which helps shorten release cycles and helps ensure code reliability. The CI/CD pipeline incorporates shift-left testing and code security tasks well before deployment, specifically at the code build, testing, and staging deployment and validation stages. The key stages in a typical CI/CD pipeline include:
Source control: Developers commit their code changes to a shared repository, ensuring all team members work with the latest version of the code. The repository acts as a “single source of truth,” which helps avoid code conflicts.
Code build: Each code commit automatically triggers a build process, which compiles the code, resolves dependencies, and generates executable files or artifacts.
Testing: Automated testing covers a comprehensive list, including unit tests, integration tests, and end-to-end tests, which verify code correctness and identify code conflicts.
Staging deployment and validation: Once the code passes testing, continuous delivery automatically sends it to a staging environment that mirrors production, where the code undergoes validation such as user acceptance testing (UAT) and performance testing.
Production deployment: Validated code is automatically and continuously deployed to the production environment, giving users the latest features, bug fixes, and software improvements in the least amount of time.
Monitoring and feedback: Post-deployment monitoring provides feedback that is used to identify problems and gain opportunities for optimization.
Industry shifts driving CI/CD adoption
Industries of all types and sizes face increased demands for faster release cycles. This means that real-time feedback, faster iterations, and continuous improvement are mission-critical requirements. The CI/CD core goals to automate and accelerate software development and deployment align well with this trend.
As organizations shift their business models to cloud-native services, they must handle complex architectures such as microservices and containers. CI/CD is an ideal approach for optimizing dynamic cloud environments, giving DevOps teams a time-saving way to improve infrastructure scalability, deployment flexibility, and resource management.
Security risks and threats also drive adoption. They continue to grow in sophistication and the amount of damage they can cause. Automated testing and security checks can be integrated within the CI/CD pipeline to help identify potential threats early in development and before vulnerable software is deployed to the production environment. CI/CD can also help balance the need for fast development with data protection and code quality.
CI/CD use cases
Automated testing and quality assurance (QA) can integrate a suite of CI/CD pipeline tests, such as unit, integration, and end-to-end tests, which are automatically triggered whenever code is committed to the CI/CD repository. This shift-left testing approach helps detect bugs and security vulnerabilities early in the pipeline, reducing the cost and effort required to fix them. Developers receive immediate feedback on their code, allowing them to address conflicts quickly. This approach also helps ensure that code changes meet quality standards before being deployed.
Continuous deployment to production uses automated tasks to minimize the risk of human error and help shorten release cycles, enabling smooth and reliable deployments. Frequent small code changes make it possible to push software updates to users without causing service downtime or disrupting the user experience.
CI/CD Implementation challenges
Several challenges can stand in the way of successfully implementing a CI/CD pipeline, including:
Security risks: Automated deployments must be configured to eliminate security vulnerabilities, especially for tasks such as secrets management, access approvals, and compliance checks. A misconfigured pipeline could release hardcoded credentials, potentially leaving the entire development environment exposed. If the pipeline skips a compliance step, a business could get hit with massive fines for regulatory noncompliance.
Testing bottlenecks: Testing must be fast, reliable, and automated so that accurate code changes are pushed with a high frequency. Slow unit or integration tests can block pipeline progress and frustrate developers. Flaky tests can reduce developers’ trust, so they may keep running those tests until they pass or abandon automation altogether and intervene with manual testing.
Incorrectly configured code repository: The shared code repository is the lynchpin of a CI/CD pipeline; it enables developers to run automated tests, catching and resolving code conflicts as quickly as possible. A broken, corrupted, or incorrectly configured repository cannot provide a single source of truth that enables the efficiency and accuracy of the pipeline.
Technical debt: As developers commit code more frequently, legacy systems can produce a bottleneck in a CI/CD pipeline. The bottleneck can magnify the impact of a single problematic commit or other pipeline tasks by propagating additional delays downstream. Technical debt can incur additional pipeline slowdowns, such as resource contention, slow or inefficient tests, and serial execution.
Workflow complexity: Complex workflows can overload the CI/CD pipeline, creating deployment bottlenecks. For example, a complex workflow might require an excessive number of code changes. This can lead to slow code builds, which could turn into low release velocities and long delays at the far end of the pipeline. If the pipeline needs an upgrade to handle complex workflows, it can be difficult and costly to implement.
Toolchain complexity and integration: Developer, operations, and security teams use the CI/CD pipeline to deploy code consistently to different CI providers, different cloud providers, and different environments such as on-premises, Jenkins, Docker, Kubernetes, and others. Typically, these teams must use different visibility levels and non-standard tools, making it tricky to build a toolchain that seamlessly and consistently orchestrates accurate code changes across the CI/CD pipeline.
The right observability tool can provide time-saving insights into resolving these implementation challenges. The next section recommends key features to look for.
Key CI/CD observability features to look for
Organizations usually have a limited range of options when selecting a CI/CD pipeline observability tool. Therefore, it is critical to choose the right observability tool, one that helps identify and troubleshoot fragmented repositories, pipeline bottlenecks, and workflow slowdowns. Also important is finding one that provides unified and granular visibility into code integration, testing, and optimization.
An optimal observability solution helps streamline and accelerate software development:
- Automated instrumentation of pipelines and tests.
- Granular visibility into the health and performance of every build, stage, and job.
- Execution time and failure rate metrics across all CI runners and hosts.
- Correlation performance degradation metrics, including relevant commits, error messages, infrastructure metrics, and logs.
- Flaky test management that helps prevent, detect, and mitigate tests that pass and fail unpredictably optimizing test reliability and velocity.
- Impact analysis that enables automatic skipping of tests that are not relevant to a code change.
Learn more
By making use of the CI/CD pipeline’s automated features and shift-left testing, organizations can shorten their service time to market, improve software quality, reliability, and security, and deliver new features and updates to users more quickly and reliably. Learn more about CI/CD pipelines:
The right observability tools help optimize the CI/CD pipeline, maximizing its value to the organization. Learn more about the Datadog CI Pipeline Visibility tool:
