A CI/CD pipeline is an automated workflow that helps software teams integrate, build, test, secure and deploy code consistently. It connects the activities involved in software delivery, reduces reliance on manual processes and gives teams faster feedback on changes.
But a successful CI/CD pipeline is not simply one that gets code into production quickly.
If automated builds are unreliable, tests provide little confidence or security is treated as a final hurdle, faster deployment can create more problems than it solves.
At Catapult CX, our experience is that an effective CI/CD pipeline depends as much on engineering discipline, shared responsibility and continuous improvement as it does on automation. The objective is to deliver software consistently while maintaining the quality, security and reliability users expect.
This guide explains how CI/CD pipelines work, the stages and components involved, and the practices that help engineering teams build and maintain effective delivery capabilities.
What Is a CI/CD Pipeline?
A Continuous Integration and Continuous Delivery (CI/CD) pipeline is the sequence of automated processes that takes software changes from a shared code repository through building, testing, validation and deployment.
It creates a repeatable route for delivering software. Each change can be checked against agreed requirements before it reaches its intended environment, helping teams identify problems earlier and reduce inconsistencies between releases.
CI/CD is a core element of modern DevOps, but the two are not interchangeable. DevOps is a broader approach to collaboration, engineering and operational responsibility. CI/CD pipelines provide the automated delivery capability that supports those practices.
Continuous Integration vs Continuous Delivery vs Continuous Deployment
The distinction between these three concepts matters because they represent different levels of automation and release control.
| Practice | What it means | Primary purpose |
|---|---|---|
| Continuous Integration (CI) | Developers regularly integrate changes into a shared codebase, with automated builds and tests providing feedback | Identify integration problems early |
| Continuous Delivery | Changes passing the required checks are kept ready for release, with a separate decision about production deployment | Make releases reliable and repeatable |
| Continuous Deployment | Changes that pass all required automated controls are deployed to production without a separate manual release decision | Automate the production release process |
Continuous delivery does not mean every release must happen automatically. An organisation may deliberately retain production approval controls, particularly where operational or regulatory risk requires them.
Continuous deployment extends automation through the production release decision. It therefore requires considerable confidence in testing, security, monitoring and recovery.
Both approaches can be valid. The appropriate choice depends on the product, operating environment and risk involved.
How Does a CI/CD Pipeline Work?
A CI/CD pipeline typically begins when a developer commits code or opens a pull request. That event triggers a workflow which checks whether the change meets the team’s requirements.
If a mandatory check fails, the pipeline should make the problem visible and prevent the change from progressing to the relevant next step.
If the required checks pass, the pipeline prepares the software for deployment or releases it automatically, depending on the organisation’s delivery model.
The workflow is not necessarily a straight line. Tests may execute in parallel, security checks may run at several points, and different applications may follow different deployment paths.
The Main Stages of a CI/CD Pipeline
A typical CI/CD pipeline contains the following activities.
| Stage | What happens | Why it matters |
|---|---|---|
| Source and integration | Code changes are committed to version control and integrated with other changes | Provides traceability and identifies integration conflicts |
| Build | Source code and dependencies are compiled, packaged or otherwise prepared | Confirms the change can produce a usable software artefact |
| Automated testing | Unit, integration and other appropriate tests validate behaviour | Detects defects and provides confidence in changes |
| Security and quality checks | Code, dependencies, configuration and other delivery assets are checked against relevant controls | Identifies risks before release |
| Deployment and release | Validated artefacts are deployed to staging or production environments | Creates a controlled, repeatable deployment process |
| Monitoring and feedback | Teams observe application behaviour, failures and service performance | Confirms the software works as intended after deployment |
This is a practical model, not a mandatory sequence. Some checks happen before the build, others after deployment, and some continue throughout the software lifecycle.
For example, automated security testing may run whenever code changes, while monitoring and vulnerability management continue after software has reached production.
The objective is to make the delivery process both repeatable and visible, so teams know what has been checked, what has failed and what is ready to move forward.
Pipeline Components and Dependencies
Understanding the stages is only part of understanding the pipeline. Teams also need to understand the components connecting them.
A pipeline generally uses:
- Triggers to start workflows when changes or scheduled events occur.
- Jobs to carry out specific tasks, such as building software or running tests.
- Runners or agents to provide the execution environments for those jobs.
- Artefacts to preserve the software outputs produced by a build.
- Dependencies to control which activities must finish before others can begin.
- Environments to define where software is tested, validated and deployed.
- Permissions and approval controls to govern access and sensitive operations.
Modern CI/CD platforms support reusable workflows and parallel execution. Where tasks do not depend on one another, running them concurrently can reduce unnecessary waiting.
However, flexibility introduces its own complexity. A heavily customised pipeline with unclear dependencies can become difficult to maintain, even if it appears efficient.
For engineering leads, the practical test is whether developers can understand why a job has run, why another has failed and what needs to happen before a change can progress.
If those answers depend on a single specialist or extensive manual investigation, the pipeline may have become an operational constraint.
For examples of how workflows and dependencies are configured, see the official GitHub Actions workflow documentation and GitLab’s guidance on job dependencies.
What Are the Benefits of CI/CD Pipelines?
The benefits of CI/CD come from reducing uncertainty and making software delivery more consistent.
When teams integrate changes frequently and validate them through a repeatable workflow, they can identify problems while those changes are still relatively small.
That provides several practical advantages.
Faster feedback
Developers do not have to wait until a major release to discover that their work conflicts with another change or causes an existing test to fail. Automated checks can identify problems earlier, when the context is still fresh.
More reliable releases
A defined build, test and deployment process reduces the inconsistencies that arise when individuals follow different manual procedures. It also makes failures easier to investigate.
Less repetitive work
Automating routine tasks frees engineers to concentrate on changes that require judgement, investigation or problem-solving. The benefit is reducing unnecessary effort, rather than automation for its own sake.
Stronger collaboration
Shared pipelines make delivery requirements more visible across development, operations and security. Teams can agree on what must happen before software is considered ready, rather than handing responsibility from one function to another.
Greater confidence in change
Smaller, well-validated changes can be easier to understand, release and recover from than large, infrequent deployments. This depends on the quality of the tests, deployment controls and recovery processes.
These benefits are not automatic.
Consider a hypothetical engineering team that has automated its build, testing and deployment processes. On paper, it has a complete CI/CD pipeline.
However, its integration tests are unreliable, deployment approvals sit in a separate process and only one engineer understands why certain jobs fail.
Although the individual stages are automated, releases still require manual investigation and coordination. Developers lose confidence in the pipeline and begin treating failed tests as routine.
The solution is not necessarily another automation tool. The team first needs to identify why the tests are unreliable, which approvals serve a necessary purpose and where technical knowledge has become concentrated.
That distinction is important: a CI/CD pipeline should improve the delivery process, not merely automate its existing weaknesses.
For a closer examination of improving established pipelines, read CI/CD Pipeline Optimisation: From Bottleneck to Value.
CI/CD Pipeline Best Practices
One of the mistakes we see in software delivery is treating successful deployment as the finish line.
When code reaches its target environment, it can be tempting to assume the pipeline has done its job.
But getting software deployed is only one part of delivery. A successful pipeline must also provide confidence that the software meets its requirements, maintains security and works reliably for customers.
Craig Cook, Principal Engineer at Catapult CX, has consistently emphasised the importance of the engineering principles behind automation.
His perspective is that the tools used to build a pipeline are secondary to the practices that make it dependable.
The following nine principles are based on guidance originally contributed by Craig Cook. They have been expanded here to reflect the broader considerations involved in designing, operating and improving modern CI/CD pipelines.
1. Create reliable and repeatable processes
Agree how software should move through development, validation and deployment. A repeatable process reduces dependence on individual knowledge and provides a foundation for improvement.
2. Automate wherever possible
Look for manual activities that are repetitive, error-prone or unnecessarily slow. Automate them where doing so improves delivery without removing controls that serve a legitimate purpose.
3. Establish version control around a shared codebase
Version control should support collaboration and traceability. Where appropriate, extend it to configuration, infrastructure definitions and other assets needed to reproduce a release.
4. Embed testing and quality assurance throughout delivery
Do not leave quality until the final deployment stage. Unit testing, integration testing and other relevant checks should provide useful feedback as changes move through the process.
5. Address the hardest problems rather than postponing them
Difficult integration issues, fragile tests and deployment dependencies rarely become easier by being ignored. Teams should make these problems visible and address the underlying causes rather than repeatedly working around them.
6. Make responsibility and accountability shared
A pipeline should not belong to the one specialist who understands its configuration. Developers, operations and security teams need clear responsibilities and enough shared knowledge to operate the process effectively.
7. Keep the customer at the centre
The purpose of delivery is not to generate successful pipeline runs. It is to put useful, reliable software into the hands of people who need it.
8. Define ‘done’ around the complete delivery outcome
A change is not finished simply because development work has stopped or a build has passed. The team must consider validation, release, operational readiness and whether the intended outcome has actually reached the customer.
9. Move beyond Continuous Integration, Continuous Delivery and Continuous Deployment to Continuous Improvement
Pipeline design is not a one-off exercise. Teams need to examine what the process is telling them, challenge assumptions and keep improving the way they work.
These principles reflect a broader point from Catapult’s engineering experience: a sophisticated toolchain cannot compensate for an unreliable delivery process.
The same emphasis on engineering capability rather than tooling alone runs through DORA’s research on software delivery capabilities.
How to Secure a CI/CD Pipeline
A CI/CD pipeline has access to valuable assets. Depending on its configuration, it may be able to read source code, retrieve credentials, modify infrastructure and deploy software into production.
That makes the pipeline itself an important part of an organisation’s security risk.
Security cannot be reduced to adding a scanning tool immediately before deployment. It needs to be considered throughout the pipeline’s design and operation.
Key controls include:
- Access management: Apply appropriate roles and permissions, limiting access to sensitive repositories, build environments and deployment capabilities.
- Secrets management: Protect credentials, tokens and other secrets rather than exposing them in code or pipeline configuration.
- Dependency security: Understand and assess third-party packages, actions and integrations used during delivery.
- Automated security testing: Integrate appropriate static, dynamic and configuration checks into the development lifecycle.
- Artefact integrity: Protect build outputs and validate that the software being deployed is the software that was approved.
- Logging and monitoring: Maintain enough visibility to investigate suspicious activity and understand changes to the delivery environment.
- Release controls: Apply appropriate approval, separation-of-duties or environment restrictions where risk demands them.
The OWASP Top 10 CI/CD Security Risks identifies weaknesses involving identity, credentials, dependency chains, pipeline execution, artefact integrity and insufficient visibility.
The NIST Secure Software Development Framework provides a broader set of practices for integrating security throughout software development.
For organisations operating in regulated environments, the challenge is to make security and governance part of the delivery process without turning every release into a sequence of disconnected manual checks. Our article on DevSecOps in regulated environments examines this in more detail.
How this works in practice
Catapult worked with a global financial services organisation to address fragmented security practices and late-stage delivery bottlenecks.
The engagement introduced automated security testing into CI/CD pipelines, established more consistent security controls and increased development-team ownership of security.
The wider security transformation delivered £200,000 in savings during its first three months through automating four security controls, alongside reduced manual intervention and improved delivery practices.
Those outcomes resulted from a broader security and operating-model transformation, not pipeline automation alone.
Read the Financial Services Security Transformation case study.
Why CI/CD Pipeline Skills and Ownership Matter
Modern CI/CD platforms make it possible to automate many delivery activities without building every component from scratch.
But easier access to tooling does not remove the need for engineering knowledge.
Craig Cook’s experience reflects a practical risk: teams can become increasingly reliant on delivery tools without developing a comparable understanding of the processes those tools automate.
When a task falls outside an existing integration’s capabilities, developers may create a workaround or depend on a specialist to resolve it.
Over time, these exceptions can make the pipeline more difficult to maintain and change.
The issue is not whether every developer can configure every part of the platform. It is whether the team has enough shared knowledge to understand how delivery works, diagnose failures and make informed changes.
For engineering leaders, that means considering:
- Who is accountable for pipeline reliability and maintenance?
- Can more than one person investigate and resolve a failed workflow?
- Are dependencies, configuration decisions and operational controls documented?
- Do developers understand the consequences of changes after deployment?
- Is pipeline knowledge being transferred as the team and tooling evolve?
Specialist expertise remains important, but it should not become a single point of failure.
A sustainable operating model requires clear ownership, appropriate documentation, shared practices and deliberate knowledge transfer.
How Modern CI/CD Pipelines Are Evolving
CI/CD pipelines have moved beyond basic build-and-deploy automation.
Modern platforms support reusable workflow components, integration with external services, more flexible execution patterns and stronger controls over deployment environments.
These capabilities can help teams standardise delivery without requiring each application team to create and maintain every element independently.
Reusable pipeline configurations, for example, can reduce duplicated work and make agreed quality or security requirements easier to apply consistently.
Parallel execution can reduce unnecessary waiting where independent jobs do not need to run in sequence.
Cloud-hosted services and managed integrations can reduce some infrastructure maintenance, while self-hosted capabilities remain appropriate where teams need particular levels of control.
The question is not which approach is most fashionable. It is which arrangement provides the reliability, flexibility and control the organisation requires.
Standardisation and self-service
As engineering organisations grow, individual teams may develop different approaches to building, testing and releasing software.
An internal platform can provide common delivery capabilities while allowing teams to manage their own applications.
But centralising the tooling does not automatically create a successful platform. Engineers still need usable interfaces, reliable services and a clear understanding of who owns shared components.
Our guide to Platform Engineering vs DevOps explores how shared platform capabilities can support DevOps practices.
Observability and operational feedback
Pipeline evolution also extends beyond the point of deployment.
At Catapult, service dashboards and operational metrics are part of creating feedback between software changes and their real-world behaviour.
A deployment may have passed every automated check while still introducing a performance issue or affecting an important customer workflow.
Monitoring and operational feedback help teams identify these consequences and determine what needs to improve.
The objective is a connected delivery capability: one in which automation, engineering decisions and operational outcomes inform one another.
How to Measure CI/CD Pipeline Performance
Pipeline success should be measured across the software delivery process rather than by deployment speed alone.
A fast pipeline that frequently introduces production failures is not performing well. Neither is a stable pipeline that creates so much delay that small changes take weeks to reach users.
DORA’s software delivery performance metrics provide a framework for assessing delivery throughput and instability together.
The current framework includes five metrics:
| Metric | What it helps teams understand |
|---|---|
| Change lead time | How long a code change takes to reach production |
| Deployment frequency | How frequently software changes are deployed |
| Failed deployment recovery time | How long it takes to recover from a failed deployment requiring immediate intervention |
| Change fail rate | What proportion of deployments require immediate intervention because of a failure |
| Deployment rework rate | What proportion of deployments involve unplanned work related to production incidents |
DORA’s framework considers change lead time, deployment frequency and failed deployment recovery time as throughput measures, alongside change fail rate and deployment rework rate as instability measures.
These metrics should be interpreted in context rather than used as universal targets for every team.
They also measure software delivery outcomes, not every problem within a pipeline.
For diagnosis, engineering teams may need additional operational measures, such as:
- Build and pipeline execution duration
- Time spent waiting for available runners or required approvals
- Automated test reliability
- Failed or repeatedly retried pipeline jobs
- Time spent investigating and resolving pipeline failures
These measures can help teams identify problems, but collecting them is not the same as resolving them.
The important question is whether the data helps engineers understand what needs to change and whether those changes improve delivery.
For a deeper examination of how pipeline delays affect engineering capacity and delivery economics, see CI/CD Pipeline Performance: The Compounding Cost of Waiting.
CI/CD Pipeline FAQs
What is a CI/CD pipeline?
A CI/CD pipeline is an automated workflow that integrates code changes, builds software, runs validation checks and prepares or deploys releases. It helps teams make software delivery more consistent, repeatable and reliable.
How does a CI/CD pipeline work?
A pipeline usually starts with a change in version control. Automated jobs then build, test and validate the change before preparing or deploying it. Dependencies, permissions and release controls determine how the workflow progresses.
Why is a CI/CD pipeline important?
It reduces reliance on manual processes, provides earlier feedback and gives teams a repeatable way to deliver software. Its value depends on effective testing, security, ownership and operational feedback.
What are CI/CD pipeline best practices?
Important practices include repeatable processes, appropriate automation, version control, continuous testing, shared accountability, customer focus and ongoing improvement. A successful deployment is not the only measure of success.
How do you secure a CI/CD pipeline?
Protect credentials, restrict permissions, assess dependencies, validate artefacts and integrate security testing throughout delivery. Security responsibilities should be shared across development, operations and security teams.
How are modern CI/CD pipelines evolving?
Modern pipelines can use reusable workflows, managed tooling, parallel execution, integrated security controls and operational monitoring. The objective is more consistent and reliable delivery, rather than automation for its own sake.
What is the difference between continuous delivery and continuous deployment?
Continuous delivery keeps software ready for release, while allowing a separate decision about production deployment. Continuous deployment automatically releases changes that have passed the required checks.
Making your CI/CD pipeline work for your team
A CI/CD pipeline provides the mechanisms for repeatable software delivery. Getting lasting value from those mechanisms requires engineering teams to understand the complete process, maintain effective controls and use feedback to improve delivery.
If an existing pipeline is underperforming, the first step should be understanding why.
Slow delivery may result from inefficient pipeline configuration, unreliable or unnecessarily extensive testing, poorly managed dependencies, or a wider problem with engineering ownership and working practices.
These causes require different interventions. Reconfiguring a pipeline will not resolve unreliable tests. Adding new tooling will not necessarily fix an unclear operating model.
Catapult’s CI/CD Pipeline Optimisation service assesses existing delivery processes to identify where changes to pipeline architecture, testing and automation can improve reliability and engineering efficiency.
The objective is not simply a faster pipeline. It is a delivery capability that engineering teams can understand, trust and continuously improve.
