What are the main practices involved in continuous delivery?

Continuous delivery is a software development approach where code updates are automatically tested and uploaded to a repository, allowing developers to focus on writing code rather than managing the delivery process. The practice ensures that code changes can be safely released at any time while reducing the time, cost, and effort required to roll out updates.

Modern teams have moved beyond traditional release cycles where deployment and feature availability were tightly coupled. The separation of code deployment from feature release has changed how organizations approach continuous delivery, making it possible to deploy code continuously without immediately exposing new functionality to users.

Building a foundation with automated testing

Automated testing forms the foundation of any continuous delivery pipeline. DevOps teams typically use automated build and test systems that check integrated code for errors and run tests to ensure the code meets required specifications. This process triggers every time code commits to the repository, with results available immediately so issues can be addressed quickly.

Comprehensive test coverage

Testing in continuous delivery extends beyond basic unit tests. Teams need comprehensive test suites that cover integration testing, performance testing, security validation, and compatibility checks. Test-driven development, where tests are written before code, helps ensure testability from the start. Testing should also reflect real-world data and actual user behaviors rather than synthetic scenarios.

Feature flags enable a particularly useful testing approach. Code can be tested in production environments without exposing new features to users. A team building a video streaming service might deploy a new recommendation algorithm behind a feature flag and run performance tests with synthetic traffic before enabling it for real users. This dramatically reduces the risk of regressions while giving teams confidence in stability before rollout.

Trunk-based development

Trunk-based development has become a crucial practice for teams pursuing continuous delivery. This approach emphasizes merging code into the main branch (the trunk) as quickly as possible. The practice reduces the complexity of long-lived feature branches, minimizes merge conflicts, and ensures teams can continuously integrate and test their code.

There are several strategies for implementing trunk-based development:

• Merging every commit directly into the main branch maximizes the rate of continuous integration and delivery, as changes integrate into the trunk as soon as they’re ready
• Merging changes at regular intervals, such as daily or before the end of each work day, offers a balance between frequent integration and managing work-in-progress
• Using short-lived feature branches enables code review processes without the burden of maintaining long-running branches that become difficult to manage over time

Feature flags solve a fundamental problem in trunk-based development. Developers can merge incomplete code into the main branch while keeping functionality hidden or disabled, ensuring the trunk remains in a releasable state. A feature might be cleaved up into pieces that span many short-lived branches, with the feature flag preventing an incomplete feature from being exposed before it’s done.

Continuous integration pipelines

Continuous integration and continuous delivery work together but serve different purposes. CI merges code from developers into a shared repository which is built automatically. Once this integration completes, the process continues through continuous delivery to ensure that changes can be reliably deployed while remaining automated and consistent across environments.

Setting up robust CI systems

A robust CI system should automate builds and tests, checking integrated code in real time as changes are committed. The system needs to detect and resolve conflicts or issues early, before they become larger problems. This helps ensure the codebase remains stable and functional at all times.

The requirements for effective CI pipelines include:

• A robust version control system like Git to track all changes
• Comprehensive automated testing suites to catch issues early and ensure code stability
• Strong team buy-in, as all team members need to understand the practices and benefits
• Automated build processes that reduce manual effort associated with building applications for different environments or devices

Feature management and release control

Feature management involves the strategic use of feature flags to control the lifecycle and rollout of features. This includes scheduling feature releases, managing access based on user roles, and monitoring feature performance and usage. Effective feature management ensures new features are released in a controlled and measured manner.

The separation of deployment from release gives teams unprecedented control. You might ship a new analytics module behind a feature flag where the code is in production but the feature isn’t live for anyone. This separation allows teams to iterate, test, and validate incrementally without the risk of prematurely exposing unfinished work.

Release flags and feature toggles

Release flags enable teams to integrate code into the mainline without immediately exposing it to all users. This practice supports continuous integration and delivery by always keeping the main branch deployable. Teams can develop and test features incrementally in production without impacting the entire user base, thereby enhancing stability and reliability.

Deployment automation and release strategies

Deployment automation creates a consistent, repeatable deployment pipeline. Many teams implement continuous deployment where software deploys automatically once it passes required tests. Rolling deployments gradually roll out updates to reduce risk and minimize user impact.

The distinction between shipping code and releasing functionality becomes critical during deployment. Deployment brings code to production, but not necessarily to users. A SaaS company might use feature flags to deploy a redesigned dashboard weeks in advance. Initially, the flag stays off. When ready, they enable it for 5% of users, then 20%, and eventually 100% without any additional deployments.

Progressive rollout strategies

This approach offers several advantages. Teams can release code continuously but only enable functionality when ready. They gain the flexibility to test features in production, do phased rollouts, and respond quickly to feedback. The practice reduces the risk of large launches and lets teams move faster without fear.

Monitoring and feedback loops

Post-release monitoring tracks both the health of deployments at the code level and the impact of features at the user level. Real-time monitoring of performance and stability helps teams quickly identify and address issues. Monitoring should capture metrics that matter for both technical performance and user behavior.

Effective monitoring requires collaboration between development and operations teams. Regular collection and incorporation of user feedback into development creates continuous improvement cycles. Customer Success teams provide valuable insights into real-world usage patterns and pain points that might not be visible through technical metrics alone.

A team that releases a new project management tool feature might see that the underlying deployment caused no issues, but monitoring shows users are confused by the interface. This signals a feature adoption problem rather than a code quality issue, requiring a different type of response.

Planning and coordination

Release management encompasses planning, scheduling, testing, deploying, and controlling software builds through different stages and environments. Well-structured planning ensures timely delivery within budget and with minimal disruption.

Defining scope and timelines

Effective planning requires defining release scope precisely, including objectives, code changes, and which features will be made available. Teams should create realistic timelines with clear deadlines for each release phase and allocate resources strategically with buffer time for unexpected changes. Mapping dependencies helps identify interdependencies between features, teams, and resources to prevent bottlenecks.

Communication as a core practice

Communication forms the foundation of successful continuous delivery. Teams need clearly defined roles and responsibilities, with everyone from development to operations understanding their specific functions in the pipeline. Short, focused meetings keep teams aligned. Creating an environment where team members feel comfortable speaking up, asking questions, and providing feedback reduces friction in the delivery process.

The practices involved in continuous delivery work together to enable teams to ship code frequently while maintaining quality and reducing risk. By automating testing, adopting trunk-based development, implementing robust CI pipelines, using feature flags for release control, and maintaining strong monitoring and communication, organizations can achieve the speed and reliability that continuous delivery promises.

Frequently asked questions

What is the difference between continuous delivery and continuous deployment?

Continuous delivery ensures code changes can be safely released at any time, with the final deployment requiring manual approval. Continuous deployment takes this further by automatically deploying all code changes to production without manual intervention once they pass automated tests. Both practices rely on automation, but continuous deployment eliminates the manual approval step.

How do feature flags support continuous delivery?

Feature flags separate code deployment from feature release, allowing teams to deploy code to production without immediately exposing functionality to users. This enables testing in production environments, progressive rollouts to subsets of users, and quick rollbacks if issues arise. Teams can ship code continuously while controlling when features become available.

What are the key requirements for implementing continuous delivery?

Successful continuous delivery requires automated testing infrastructure, a robust CI/CD pipeline, version control systems, strong team collaboration, and comprehensive monitoring. Teams also need buy-in from all stakeholders and a cultural shift toward frequent, small releases rather than large, infrequent deployments.

How does trunk-based development relate to continuous delivery?

Trunk-based development supports continuous delivery by having all developers merge code into a single main branch frequently. This reduces merge conflicts, enables continuous integration, and keeps the codebase in a constantly releasable state. Feature flags allow incomplete features to exist in the trunk without affecting users.

What role does automated testing play in continuous delivery?

Automated testing provides the confidence needed to release frequently. Every code change triggers automated tests that verify functionality, performance, and security. Without comprehensive automated testing, teams cannot safely deploy code multiple times per day or maintain the quality standards continuous delivery requires.

How often should teams release with continuous delivery?

Release frequency depends on team maturity, product complexity, and business needs. Some teams deploy multiple times daily, while others release weekly. The goal is to release as frequently as possible while maintaining quality. Feature flags enable daily code deployments even when features aren’t ready for full release.