Today, in the world of software development, almost all of the code created by software developers is done collaboratively from various locations and with a focus on solving complex problems. However, this creates several challenges for teamwork to be efficient, such as avoiding overwriting someone else’s work, experimenting with new ideas without messing up the main product, and keeping track of who did what and why.
Version control has the answer to these problems, and the most popular version control tool among teams is Git. Over the course of time, Git has become the connective force for the continuous integration process used by the vast majority of developers (87% have Git as their primary version control system), which is essential in ensuring that teams can collaborate on software projects. Additionally, Git does much more than just save the code typed by a developer; it serves as a foundation for improving team communication, execution, and delivery of software.
This article will examine how the various features of Git provide teams with the tools necessary to improve and enhance the development of collaborative software from establishing a defined source of truth to supporting the use of sophisticated workflows that allow modern DevOps to execute at a high level.
The Foundation: A Distributed “Single Source of Truth”
Git has developed as an answer to a simple question: how do I keep track of when files have changed over time? In contrast to older centralized version control systems, Git is built on a distributed model. Every member of the development team has a complete copy of the project’s entire history on their local machine. This allows teams to have:
True parallelism – Team members can work offline, create commits on their local machine, and experiment freely without needing to constantly connect to a central server. They do not have to deal with delays in communication due to the network or outages caused by problems with the server.
A single “source of truth” for the team – GitHub, GitLab, or Bitbucket all offer a central repository; therefore, the team has one official version or representation of the code, which serves as the coordination point for all members of the team. This repository contains the “master” copy of the code that every developer will eventually use. Since there is a centralized source of truth, there is an environment that allows for lots of local flexibility combined with a central location where code is shared, reviewed, and merged. Thus, there will always be work taking place on the project, and the history of the project will remain intact regardless of what happens locally.
1. Parallel Development Through Isolated Experimentation
The idea of branching is what really propels team productivity with Git; through the use of branching, Git allows developers to have isolated copies of the codebase that can then be used to accomplish a particular task without affecting anything outside of that branch.
Let’s say you have a team developing a critical web application. One developer is going to fix a security vulnerability, another is building a new user dashboard, and the third is refactoring the way the application connects to its database; without Git, this would be a chaotic mixture of multiple folders containing the same files and manual file merging. Using Git makes all of this possible:
- The developer fixing the security bug creates a hotfix/login-bug branch based on the main branch in the source repository.
- The developer building the new user dashboard creates a feature/new-dashboard branch based on the main branch in the source repository.
- The developer refactoring the database connection layer creates a refactor/database- layer branch based on the main branch in the source repository.
By doing this, each developer has their own isolated sandbox separated from the instability being created by other developers. They are also able to make breaking changes, try things out, and even fail without putting at risk the stable application that users are currently relying on. The ability for developers to work in isolation in their own branches in parallel allows a team to exponentially increase its productivity by being able to work on multiple projects simultaneously without crossing paths. The ability to branch in Git can also help decrease coding errors through the elimination of the risks associated with committing broken files.
2. Establishing a Predictable and Scalable Workflow
A branching model’s success is determined by the quality of the workflow supporting it. Because of Git’s flexibility, teams can build and enforce a consistent process that works well given their release cycles and risk appetite. Predictability enhances team morale and helps maintain project management. There are a few different strategies that serve varying types of team needs.
GitHub Flow is the definition of simplicity. GitHub Flow primarily consists of the main branch (or “master”) and the feature branch (or “feature”). Developers create a branch, make changes, then open a pull request (or “PR”), which is reviewed before being merged back into the main branch. This type of workflow works best with developers who follow a continuous delivery (CD) model because it allows them to ship changes quickly and consistently.
GitFlow is a more sophisticated Gerrit/Git branching and merging model for projects that have scheduled releases and support needs. The model has several components, including the develop branch, where development is integrated, and an ongoing release branch that maintains a stable version of a project while allowing hot fix branches to be created if an emergency patch is needed in production directly from the main branch. Although very powerful, many small teams can find GitFlow very complicated.
Trunk-Based Development is an approach that is usually adopted by large, high-performing teams (e.g., Google, Facebook). Developers merge small, frequent changes to and from a shared main branch (aka “the trunk”) daily (usually many times). This type of flow will result in fewer merge conflicts and will eliminate the difficulty of dealing with long-term branches; however, it does require
3. Code Review: The Engine of Quality and Knowledge
A branch is just a place to put work, while the actual magic of collaboration happens when a developer wants to merge that work back into the shared code base. The way this happens is through either a Pull or Merge Request(PR or MR). The pull request itself is the primary feature of modern Git hosting platforms. The Pull/Merge Request is not merely a request to merge code, but rather a collaborative area where developers can discuss their logic, style, and how they will implement a code change (i.e., PR/MR).
The very act of opening a PR is essentially inviting your teammates to review your logic, style, and how you plan to implement your code. This creates a formalized “gate” to produce quality code. Reviewers will have the opportunity to identify possible bugs, security vulnerabilities, and/or issues with the performance of the code long before ever going to production environments.
But the benefits of a PR/MR extend well beyond bug prevention. Code reviews often become an important mechanism for sharing knowledge amongst team members. For example, a junior developer may learn the idiomatic syntax of a programming language from a senior developer’s feedback on a code review. Similarly, a back-end specialist learns how the front-end team will interface with the back-end APIs by reviewing the code in conjunction with the front-end team’s PR/MR. Through this type of “cross-pollination” of knowledge within the organization, they can create a more resilient development team by breaking down any silo which previously existed as the result of having all of their knowledge locked in one individual’s head, thereby also creating a living document for any developer who looks at the code in the future – explaining the “why” behind a code change.
4. The Safety Net: Fearless Experimentation and Recovery
Developing software can involve a lot of risk. There is a chance that a new feature will go in an unexpected direction, or that a fix for a bug will have unexpected results. The tools provided by Git (both psychologically and technically) are essential to help encourage teams to take risks and act boldly.
The first layer of this safety net provided by Git is the commit history. There is visibility of every change made to the codebase – Git stores the history of everything that happens to it. The use of SHA-1 checksums to ensure the integrity of the data (meaning that the history cannot be altered without Git knowing about it) allows developers to be able to answer questions such as “When was this line last changed, and why did it change?” (using git blame), and “What was changed in this release?”
The second layer of the safety net is the ability to revert. If there is a catastrophic failure with a deployment, reverting to a previously deployed commit is frequently a one-click event. This ability to immediately return to a known good state from a previously deployed commit removes a lot of stress from the process of deploying code, as well as decreases the mean-time-to-recovery (MTTR) for incidents that occur.
Additionally, because branching is so inexpensive with Git, teams are able to experiment with ideas without constraint. For example, if a team wishes to experiment with a new library, major architectural changes, or a wild idea, they would create a branch to do so, and if successful, they would merge that branch with the master branch. If they are unsuccessful, they simply delete the branch. All of this provides an environment with an extremely low level of risk, which supports teams in successfully deploying code.
5. Beyond Code: Git for the Whole Team (Docs, Ops, and Config)
Git is Useful for More than Just Developers: As a company adopts DevOps principles, it will find that the principles behind version control apply across-the-board. With the increasing adoption of Infrastructure-as-Code (IaC), Ops teams are now leveraging Git to manage their server configurations, network rules, cloud provisioning scripts, etc. This means that any changes to your infrastructure will be subject to the same review process, using the same formality and level of detail in versioning as you would for application code. In turn, this will provide you with a much more stable and auditable environment.
Additionally, people outside of engineering can find value in Git. Product Managers can use Git to manage their product requirement documents and version them as appropriate. Technical writers will be able to collaborate on documentation, and QA engineers will have access to their testing plans and scripts via the same single source of truth (the Git repository). By storing all project artifacts together in a single Git repository, there will be much less separation between departments or departments within the organization. Therefore, by working from a single source of truth, the organization becomes more cohesive and aligned.
Best Practices for Maximum Team Efficiency
For getting the most out of Git, teams will need to implement discipline and best practices. As with any other tool, Git is only as effective as the overall process that supports using it.
Write Meaningful (“descriptive”) Commit Messages: “Fix stuff” is not a descriptive commit message and will not help anyone. Teams should adopt a consistent naming convention for commits, such as using the Conventional Commit specification (e.g., feat: add user login endpoint), so that a readable and processable history is maintained.
Commit Frequently and in Small “Chunks”: Large, monolithic commits are difficult to review and even more difficult to troubleshoot later. Developers should thus be encouraged to commit multiple logical changes in the same commit frequently. Doing so will conform to trunk-based development principles and help facilitate rollbacks to specific changes if necessary.
Keep Branches Short-Lived: A branch that exists for several weeks is a high probability for a merge conflict. In addition, such a long-lived branch will have diverged from the mainline so that integrating later will be especially painful.
Protect the Main Branch: Use branch protection rules to prevent direct commits to critical branches (e.g., main, develop). Require Pull Request (PR) approvals from one or more code owners to facilitate the safe operation of the stable build.
Automate Everything: Integrate your Git repository with a CI/CD pipeline so that every time a push or pull request occurs, builds and tests will be automatically triggered. As such, there will always be a logical link between the code submitted and its testing results. Automating will also ensure that, at all times, there is a continuous integration process between development and production environments.
Conclusion
The advent of Git has changed the landscape of collaborative software development for teams. Git gives professional software development teams a solid foundation for effective collaboration, taking away the chaos of shared drives and overwriting files, and providing a structured, secure, and efficient way to work together to build great software products. Git’s powerful branching model allows multiple teams to develop in parallel and at scale by factoring out the concern of merge conflicts into a practical way of doing parallel version control. With pull requests, Git provides a foundation for code review, facilitating higher quality of code as well as sharing skills and experience among team members. With a complete history of all activities in a Git repository, development teams can confidently experiment without risk.
Thus, Git is not just a source control tool (although it is the best one); it is also a collaboration platform that, when used in conjunction with a well-defined workflow and team members who have discipline, enables the transformation of a group of people into a highly productive and well-functioning team of software developers. Git is the best-kept secret in every successful, collaborative software project; it guarantees that the finished product is greater than just the sum of the individual parts.
