Trunk-Based Development in Software Development

In earlier days of software development, programmers didn’t have the richness of modern version control systems but they developed two versions of their software concurrently as it means of monitoring small changes and backing them if possible and only in necessary conditions. As time increases it has become more costly, and inefficient.

Trunk Based Development

At present various version control systems are developed and managed. It made it more mature, and various departments have merged which enables programmers to find bugs or errors more easily. As of today most developers hold one of the two development models in order to deliver quality software which is Git flow and trunk-based development. Trunk-based development is an additional open model since all developers have easier access to the main code which also enables teams to implement CI/CD and so on.

What is Trunk Based Development?

In software development, Trunk based development is a version control management technique or practice where developers from various organizations merge small, regular updates to a base code.

• It is a common practice among DevOps teams and part of DevOps lifecycle since it streamlines merging and integration phases. Copies made from the source code is called branches.
• It is considered as an branching model. In fact, trunk-based development is a required practice of CI/CD. As codebase complexity and team size grow, trunk-based development helps us to keep production releases flowing and here errors are addressed quickly and remediated before they go live.

Importance of Trunk-Based Development

1. Faster Time to Market: By promoting simple terms, frequent contributions and continuous integration, trunk-based development speeds up delivery.
2. Reduced Integration Problems: Early problem detection and resolution are achieved by continuous integration, and working directly on the main branch reduces conflicts.
3. Enhanced Cooperation: By collaborating on the main root, solitary work on different branches is avoided and communication and information sharing are encouraged.
4. Simpler Code Reviews: Code reviews are easier to manage when changes are smaller and more frequent, which allows for quicker iterations and quicker feedback.
5. Enhanced Transparency: The main branch offers a transparent picture of the project’s status and the present state of the codebase since it acts as a single source of truth.
6. Adaptability to Change: Trunk-Based Development facilitates quick pivots, responsiveness to changing requirements, and effective feedback assimilation, all of which help to increase adaptability to change.

Git flow vs. Trunk-Based Development

Git Flow/ Feature Branch vs Trunk Based Development

Below is the side by side comparison between Git-Flow and Trunk Based Development:

Feature	Git Flow	Trunk Based Development
Branching Model	Complex branching model with multiple branches (master, develop, feature, release, hotfix).	Simple branching model with a primary focus on a single branch (master or main).
Release Cycle	Structured release cycle with dedicated branches for feature development, release preparation, and hotfixes.	Emphasizes continuous integration with releases made directly from the main branch. Features are often developed in short-lived branches.
Stability	Promotes a more stable develop branch for ongoing development; master is intended to represent the latest production-ready state.	Emphasizes continuous integration, and the main branch is expected to be in a releasable state at all times
Isolation of features	Features are developed in separate branches (feature branches), allowing for isolation and testing before merging into the main development branch.	Features are often developed in short-lived branches, providing isolation and quick integration into the main branch.
Complexity	Introduces additional complexity and overhead due to multiple branch types and the need to manage merges between them.	Simpler and minimizes the number of long-lived branches, reducing the complexity of the version control system.
Continuous Integration	Integrated into the workflow but not the primary emphasis. Feature branches are merged into develop through pull requests.	Primary focus on continuous integration, with developers frequently merging changes into the main branch to ensure a continuously releasable state.
Release Requirements	Suitable for projects with strict release schedules and the need to manage multiple versions simultaneously.	Well-suited for continuous delivery approaches with a focus on frequent, smaller releases.
Risk Tolerance	Provides more controlled integration, reducing the risk of conflicts and instability in the main branches.	Seen as riskier due to the frequent integration into the main branch. Requires robust testing and automation.

Considerations for Choosing:

• Team Size and Structure:
  • Git Flow may be suitable for larger teams with a structured development process, while Trunk Based Development might be more agile and suitable for smaller teams.
• Release Requirements:
  • Git Flow may be preferable for projects with strict release schedules and version management needs. Trunk Based Development is ideal for continuous delivery approaches.
• Risk Tolerance:
  • Teams with a lower tolerance for integration risks may find Git Flow more reassuring, while teams emphasizing continuous integration may lean towards Trunk Based Development.

Benefits of using Trunk-based development

Reduced complexity is a major emphasis of trunk-based software design. Trunk based development is a required practice for continuous integration. Here if the build and test processes are automated then developers work on isolated, lengthy feature branches that are infrequently integrated into a shared branch, continuous integration is not living up to its potential.

1. Allows continuous code integration:– In trunk based development model, there will be a repository with a steady stream of commits flowing into the main branch. By including an automated test suite and code coverage tracking or monitoring for the stream of commits that enables CI. When new code is merged into the trunk, automated integration and code coverage tests run to validate the code quality.
2. Ensures continuous code review:– The rapid, small commits of trunk-based development make code review a more efficient process. With small branches, developers can quickly see and review small changes. This is far easier compared to a long-lived feature branch where a reviewer reads pages of code or manually inspects a large surface area of code changes.
3. Foster collaboration:– Developers from companies can see all changes and can cross pollinate each others contributions.
4. Enables consecutive production code releases:– The teams should make frequent, daily merges to the main branch. Trunk-based development strives to keep the trunk branch “green”, which means its ready to deploy at any commit. Automated tests, code coverage, and code reviews provides a trunk-based development project with the assurances its ready to deploy to production at any time. This gives team agility to frequently deploy to production and set further goals of daily production releases.
5. Improve refactoring:– Decomposing an application story into a continuous small components takes less time.

Best practices of Trunk based development

The principle behind trunk-based development is to assimilate every change as soon as possible in version control. It ensures the teams to release code quickly and consistently. The following is a list of exercises and practices that will help will refine your teams cadence and develop an optimized release schedule. In Software Development best practices for trunk-based development include the following steps as mentioned here.

• Develop in small batches:– It follows a quick rhythm to deliver code to production. if trunk-based development was like music it would be a short notes in rapid succession, with the repository commits being the notes.
• Feature flags:– It is nicely complement trunk-based development by enabling developers to wrap new changes in an inactive code path and activate it at a later time. This allows developers to forgo creating a separate repository feature branch and instead commit new feature code directly to the main branch within a feature flag path.
• Build fast and execute immediately:– In order to maintain a quick release cadence, build and test execution times should be optimized. CI/CD build tools should use caching layers where appropriate to avoid expensive computations for static.
• Having reduced number of code freezes and integration phases:– Trunk based development teams should try to avoid blocking code freezes and plan accordingly to ensure the release pipeline is not stalled. It updates are constantly flowing.
• It perform asynchronous code reviews:– In trunk-based development, code review should be performed immediately and not put into an asynchronous system for later review. Automated tests provide a layer of pre-emptive code review. It gives the reviewer immediate reassurance that the new code meets specific specifications.
• It simple to conclude that Develop, Code, Commit, Plan, Test, Manage.

Future Trends in Trunk-Based Development

1. Practices for Collaborative Coding: Ongoing development of more cooperative coding techniques, maybe including functionalities like in-development real-time pair programming support.
2. Integration of Security: Direct integration of security measures with the TBD workflow guarantees smooth security scans and checks as part of the ongoing integration process.
3. International Cooperation and Support for Remote Work: Modifying TBD procedures to more effectively facilitate remote work and international collaboration, with an emphasis on lowering obstacles to communication for dispersed teams.
4. Immutable Infrastructure and Infrastructure as Code (IaC): Alignment of TBD with new paradigms such as Infrastructure as Code (IaC) and Immutable Infrastructure, with a focus on versioning and configuration management of infrastructure changes within the main branch.

Conclusion

In this article we have came across trunk based development and its benefits, practices. It is currently the standard for high performing engineering teams since it sets and maintains a software release cadence by using a simplified git branching strategy. Trunk-based development gives engineering teams more flexibility and control over how they deliver software to the end user.