Git is a free and open source distributed version control system designed to handle everything from small to very large projects with speed and efficiency.
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Switching from a centralized version control system to Git changes the way your development team creates software. And, if you’re a company that relies on its software for mission-critical applications, altering your development workflow impacts your entire business.
In this article, we’ll discuss how Git benefits each aspect of your organization, from your development team to your marketing team, and everything in between. By the end of this article, it should be clear that Git isn’t just for agile software development—it’s for agile business.
Git for developers
Feature Branch Workflow
One of the biggest advantages of Git is its branching capabilities. Unlike centralized version control systems, Git branches are cheap and easy to merge. This facilitates the feature branch workflow popular with many Git users.
Feature branches provide an isolated environment for every change to your codebase. When a developer wants to start working on something—no matter how big or small—they create a new branch. This ensures that the master branch always contains production-quality code.
Using feature branches is not only more reliable than directly editing production code, but it also provides organizational benefits. They let you represent development work at the same granularity as the your agile backlog.
In SVN, each developer gets a working copy that points back to a single central repository. Git, however, is a distributed version control system. Instead of a working copy, each developer gets their own local repository, complete with a full history of commits.
Having a full local history makes Git fast, since it means you don’t need a network connection to create commits, inspect previous versions of a file, or perform diffs between commits.
Distributed development also makes it easier to scale your engineering team. If someone breaks the production branch in SVN, other developers can’t check in their changes until it’s fixed. With Git, this kind of blocking doesn’t exist. Everybody can continue going about their business in their own local repositories.
And, similar to feature branches, distributed development creates a more reliable environment. Even if a developer obliterates their own repository, they can simply clone someone else’s and start anew.
Many source code management tools such as Github, Gitlab & Bitbucket enhance core Git functionality with pull requests. A pull request is a way to ask another developer to merge one of your branches into their repository. This not only makes it easier for project leads to keep track of changes, but also lets developers initiate discussions around their work before integrating it with the rest of the codebase.
Since they’re essentially a comment thread attached to a feature branch, pull requests are extremely versatile. When a developer gets stuck with a hard problem, they can open a pull request to ask for help from the rest of the team. Alternatively, junior developers can be confident that they aren’t destroying the entire project by treating pull requests as a formal code review.
In many circles, Git has come to be the expected version control system for new projects. If your team is using Git, odds are you won’t have to train new hires on your workflow, because they’ll already be familiar with distributed development.
In addition, Git is very popular among open source projects. This means it’s easy to leverage 3rd-party libraries and encourage others to fork your own open source code.
Faster Release Cycle
The ultimate result of feature branches, distributed development, pull requests, and a stable community is a faster release cycle. These capabilities facilitate an agile workflow where developers are encouraged to share smaller changes more frequently. In turn, changes can get pushed down the deployment pipeline faster than the monolithic releases common with centralized version control systems.
As you might expect, Git works very well with continuous integration and continuous delivery environments. Git hooks allow you to run scripts when certain events occur inside of a repository, which lets you automate deployment to your heart’s content. You can even build or deploy code from specific branches to different servers.
For example, you might want to configure Git to deploy the most recent commit from the develop branch to a test server whenever anyone merges a pull request into it. Combining this kind of build automation with peer review means you have the highest possible confidence in your code as it moves from development to staging to production.
Git for marketing
To understand how switching to Git affects your company’s marketing activities, imagine your development team has three distinct changes scheduled for completion in the next few weeks:
- The entire team is finishing up a game-changing feature that they’ve been working on for the last 6 months.
- Mary is implementing a smaller, unrelated feature that only impacts existing customers.
- Rick is making some much-needed updates to the user interface.
If you’re using a traditional development workflow that relies on a centralized VCS, all of these changes would probably be rolled up into a single release. Marketing can only make one announcement that focuses primarily on the game-changing feature, and the marketing potential of the other two updates is effectively ignored.
The shorter development cycle facilitated by Git makes it much easier to divide these into individual releases. This gives marketers more to talk about, more often. In the above scenario, marketing can build out three campaigns that revolve around each feature, and thus target very specific market segments.
For instance, they might prepare a big PR push for the game changing feature, a corporate blog post and newsletter blurb for Mary’s feature, and some guest posts about Rick’s underlying UX theory for sending to external design blogs. All of these activities can be synchronized with a separate release.
Git for product management
The benefits of Git for product management is much the same as for marketing. More frequent releases means more frequent customer feedback and faster updates in reaction to that feedback. Instead of waiting for the next release 8 weeks from now, you can push a solution out to customers as quickly as your developers can write the code.
The feature branch workflow also provides flexibility when priorities change. For instance, if you’re halfway through a release cycle and you want to postpone one feature in lieu of another time-critical one, it’s no problem. That initial feature can sit around in its own branch until engineering has time to come back to it.
This same functionality makes it easy to manage innovation projects, beta tests, and rapid prototypes as independent codebases.
Git for designers
Feature branches lend themselves to rapid prototyping. Whether your UX/UI designers want to implement an entirely new user flow or simply replace some icons, checking out a new branch gives them a sandboxed environment to play with. This lets designers see how their changes will look in a real working copy of the product without the threat of breaking existing functionality.
Encapsulating user interface changes like this makes it easy to present updates to other stakeholders. For example, if the director of engineering wants to see what the design team has been working on, all they have to do is tell the director to check out the corresponding branch.
Pull requests take this one step further and provide a formal place for interested parties to discuss the new interface. Designers can make any necessary changes, and the resulting commits will show up in the pull request. This invites everybody to participate in the iteration process.
Perhaps the best part of prototyping with branches is that it’s just as easy to merge the changes into production as it is to throw them away. There’s no pressure to do either one. This encourages designers and UI developers to experiment while ensuring that only the best ideas make it through to the customer.
Git for customer support
Customer support and customer success often have a different take on updates than product managers. When a customer calls them up, they’re usually experiencing some kind of problem. If that problem is caused by your company’s software, a bug fix needs to be pushed out as soon as possible.
Git’s streamlined development cycle avoids postponing bug fixes until the next monolithic release. A developer can patch the problem and push it directly to production. Faster fixes means happier customers and fewer repeat support tickets. Instead of being stuck with, “Sorry, we’ll get right on that” your customer support team can start responding with “We’ve already fixed it!
Git for human resources
To a certain extent, your software development workflow determines who you hire. It always helps to hire engineers that are familiar with your technologies and workflows, but using Git also provides other advantages.
Employees are drawn to companies that provide career growth opportunities, and understanding how to leverage Git in both large and small organizations is a boon to any programmer. By choosing Git as your version control system, you’re making the decision to attract forward-looking developers.
Git for anyone managing a budget
Git is all about efficiency. For developers, it eliminates everything from the time wasted passing commits over a network connection to the man hours required to integrate changes in a centralized version control system. It even makes better use of junior developers by giving them a safe environment to work in. All of this affects the bottom line of your engineering department.
But, don’t forget that these efficiencies also extend outside your development team. They prevent marketing from pouring energy into collateral for features that aren’t popular. They let designers test new interfaces on the actual product with little overhead. They let you react to customer complaints immediately.
Being agile is all about finding out what works as quickly as possible, magnifying efforts that are successful, and eliminating ones that aren’t. Git serves as a multiplier for all your business activities by making sure every department is doing their job more efficiently.
A Git Workflow is a recipe or recommendation for how to use Git to accomplish work in a consistent and productive manner. Git workflows encourage users to leverage Git effectively and consistently. Git offers a lot of flexibility in how users manage changes. Given Git’s focus on flexibility, there is no standardized process on how to interact with Git. When working with a team on a Git managed project, it’s important to make sure the team is all in agreement on how the flow of changes will be applied. To ensure the team is on the same page, an agreed upon Git workflow should be developed or selected. There are several publicized Git workflows that may be a good fit for your team. Here, we’ll be discussing some of these workflow options.
The array of possible workflows can make it hard to know where to begin when implementing Git in the workplace. This page provides a starting point by surveying the most common Git workflows for software teams.
As you read through, remember that these workflows are designed to be guidelines rather than concrete rules. We want to show you what’s possible, so you can mix and match aspects from different workflows to suit your individual needs.
What is a successful Git workflow?
When evaluating a workflow for your team, it’s most important that you consider your team’s culture. You want the workflow to enhance the effectiveness of your team and not be a burden that limits productivity. Some things to consider when evaluating a Git workflow are:
- Does this workflow scale with team size?
- Is it easy to undo mistakes and errors with this workflow?
- Does this workflow impose any new unnecessary cognitive overhead to the team?
The Centralized Workflow is a great Git workflow for teams transitioning from SVN. Like Subversion, the Centralized Workflow uses a central repository to serve as the single point-of-entry for all changes to the project. Instead of
trunk, the default development branch is called
master and all changes are committed into this branch. This workflow doesn’t require any other branches besides
Transitioning to a distributed version control system may seem like a daunting task, but you don’t have to change your existing workflow to take advantage of Git. Your team can develop projects in the exact same way as they do with Subversion.
However, using Git to power your development workflow presents a few advantages over SVN. First, it gives every developer their own local copy of the entire project. This isolated environment lets each developer work independently of all other changes to a project – they can add commits to their local repository and completely forget about upstream developments until it’s convenient for them.
Second, it gives you access to Git’s robust branching and merging model. Unlike SVN, Git branches are designed to be a fail-safe mechanism for integrating code and sharing changes between repositories. The Centralized Workflow is similar to other workflows in its utilization of a remote server-side hosted repository that developers push and pull form. Compared to other workflows, the Centralized Workflow has no defined pull request or forking patterns. A Centralized Workflow is generally better suited for teams migrating from SVN to Git and smaller size teams.
How it works
Developers start by cloning the central repository. In their own local copies of the project, they edit files and commit changes as they would with SVN; however, these new commits are stored locally – they’re completely isolated from the central repository. This lets developers defer synchronizing upstream until they’re at a convenient break point.
To publish changes to the official project, developers “push” their local
master branch to the central repository. This is the equivalent of
svn commit, except that it adds all of the local commits that aren’t already in the central
Initialize the central repository
First, someone needs to create the central repository on a server. If it’s a new project, you can initialize an empty repository. Otherwise, you’ll need to import an existing Git or SVN repository.
Central repositories should always be bare repositories (they shouldn’t have a working directory), which can be created as follows:
ssh user@host git init --bare /path/to/repo.git
Be sure to use a valid SSH username for
user, the domain or IP address of your server for
host, and the location where you’d like to store your repo for
/path/to/repo.git. Note that the
.gitextension is conventionally appended to the repository name to indicate that it’s a bare repository.
Hosted central repositories
Central repositories are often created through 3rd party Git hosting services. The process of initializing a bare repository discussed above is handled for you by the hosting service. The hosting service will then provide an address for the central repository to access from your local repository.
Clone the central repository
Next, each developer creates a local copy of the entire project. This is accomplished via the
git clone command:
git clone ssh://user@host/path/to/repo.git
When you clone a repository, Git automatically adds a shortcut called
origin that points back to the “parent” repository, under the assumption that you’ll want to interact with it further on down the road.
Make changes and commit
Once the repository is cloned locally, a developer can make changes using the standard Git commit process: edit, stage, and commit. If you’re not familiar with the staging area, it’s a way to prepare a commit without having to include every change in the working directory. This lets you create highly focused commits, even if you’ve made a lot of local changes.
git status # View the state of the repo git add <some-file> # Stage a file git commit # Commit a file</some-file>
Remember that since these commands create local commits, John can repeat this process as many times as he wants without worrying about what’s going on in the central repository. This can be very useful for large features that need to be broken down into simpler, more atomic chunks.
Push new commits to central repository
Once the local repository has new changes committed. These change will need to be pushed to share with other developers on the project.
git push origin master
This command will push the new committed changes to the central repository. When pushing changes to the central repository, it is possible that updates from another developer have been previously pushed that contain code which conflict with the intended push updates. Git will output a message indicating this conflict. In this situation,
git pull will first need to be executed. This conflict scenario will be expanded on in the following section.
The central repository represents the official project, so its commit history should be treated as sacred and immutable. If a developer’s local commits diverge from the central repository, Git will refuse to push their changes because this would overwrite official commits.
Before the developer can publish their feature, they need to fetch the updated central commits and rebase their changes on top of them. This is like saying, “I want to add my changes to what everyone else has already done.” The result is a perfectly linear history, just like in traditional SVN workflows.
If local changes directly conflict with upstream commits, Git will pause the rebasing process and give you a chance to manually resolve the conflicts. The nice thing about Git is that it uses the same
git status and
git add commands for both generating commits and resolving merge conflicts. This makes it easy for new developers to manage their own merges. Plus, if they get themselves into trouble, Git makes it very easy to abort the entire rebase and try again (or go find help).
Let’s take a general example at how a typical small team would collaborate using this workflow. We’ll see how two developers, John and Mary, can work on separate features and share their contributions via a centralized repository.
John works on his feature
In his local repository, John can develop features using the standard Git commit process: edit, stage, and commit.
Remember that since these commands create local commits, John can repeat this process as many times as he wants without worrying about what’s going on in the central repository.
Mary works on her feature
Meanwhile, Mary is working on her own feature in her own local repository using the same edit/stage/commit process. Like John, she doesn’t care what’s going on in the central repository, and she really doesn’t care what John is doing in his local repository, since all local repositories are private.
John publishes his feature
Once John finishes his feature, he should publish his local commits to the central repository so other team members can access it. He can do this with the
git push command, like so:
git push origin master
origin is the remote connection to the central repository that Git created when John cloned it. The
masterargument tells Git to try to make the
master branch look like his local
master branch. Since the central repository hasn’t been updated since John cloned it, this won’t result in any conflicts and the push will work as expected.
Mary tries to publish her feature
Let’s see what happens if Mary tries to push her feature after John has successfully published his changes to the central repository. She can use the exact same push command:
git push origin master
But, since her local history has diverged from the central repository, Git will refuse the request with a rather verbose error message:
error: failed to push some refs to '/path/to/repo.git' hint: Updates were rejected because the tip of your current branch is behind hint: its remote counterpart. Merge the remote changes (e.g. 'git pull') hint: before pushing again. hint: See the 'Note about fast-forwards' in 'git push --help' for details.
This prevents Mary from overwriting official commits. She needs to pull John’s updates into her repository, integrate them with her local changes, and then try again.
Mary rebases on top of John’s commit(s)
Mary can use
git pull to incorporate upstream changes into her repository. This command is sort of like
svn update—it pulls the entire upstream commit history into Mary’s local repository and tries to integrate it with her local commits:
git pull --rebase origin master
--rebase option tells Git to move all of Mary’s commits to the tip of the
master branch after synchronising it with the changes from the central repository, as shown below:
The pull would still work if you forgot this option, but you would wind up with a superfluous “merge commit” every time someone needed to synchronize with the central repository. For this workflow, it’s always better to rebase instead of generating a merge commit.
Mary resolves a merge conflict
Rebasing works by transferring each local commit to the updated
master branch one at a time. This means that you catch merge conflicts on a commit-by-commit basis rather than resolving all of them in one massive merge commit. This keeps your commits as focused as possible and makes for a clean project history. In turn, this makes it much easier to figure out where bugs were introduced and, if necessary, to roll back changes with minimal impact on the project.
If Mary and John are working on unrelated features, it’s unlikely that the rebasing process will generate conflicts. But if it does, Git will pause the rebase at the current commit and output the following message, along with some relevant instructions:
CONFLICT (content): Merge conflict in <some-file>
The great thing about Git is that anyone can resolve their own merge conflicts. In our example, Mary would simply run a
git status to see where the problem is. Conflicted files will appear in the Unmerged paths section:
Unmerged paths: (use "git reset HEAD <some-file>..." to unstage) (use "git add/rm <some-file>..." as appropriate to mark resolution) both modified: <some-file>
Then, she’ll edit the file(s) to her liking. Once she’s happy with the result, she can stage the file(s) in the usual fashion and let
git rebase do the rest:
git add <some-file> git rebase --continue
And that’s all there is to it. Git will move on to the next commit and repeat the process for any other commits that generate conflicts.
If you get to this point and realize and you have no idea what’s going on, don’t panic. Just execute the following command and you’ll be right back to where you started:
git rebase --abort
Mary successfully publishes her feature
After she’s done synchronizing with the central repository, Mary will be able to publish her changes successfully:
git push origin master
Where to go from here
As you can see, it’s possible to replicate a traditional Subversion development environment using only a handful of Git commands. This is great for transitioning teams off of SVN, but it doesn’t leverage the distributed nature of Git.
The Centralized Workflow is great for small teams. The conflict resolution process detailed above can form a bottleneck as your team scales in size. If your team is comfortable with the Centralized Workflow but wants to streamline its collaboration efforts, it’s definitely worth exploring the benefits of the Feature Branch Workflow. By dedicating an isolated branch to each feature, it’s possible to initiate in-depth discussions around new additions before integrating them into the official project.
Other common workflows
The Centralized Workflow is essentially a building block for other Git workflows. Most popular Git workflows will have some sort of centralized repo that individual developers will push and pull from. Below we will briefly discuss some other popular Git workflows. These extended workflows offer more specialized patterns in regard to managing branches for feature development, hot fixes, and eventual release.
Feature Branching is a logical extension of Centralized Workflow. The core idea behind the Feature Branch Workflow is that all feature development should take place in a dedicated branch instead of the
master branch. This encapsulation makes it easy for multiple developers to work on a particular feature without disturbing the main codebase. It also means the
master branch should never contain broken code, which is a huge advantage for continuous integration environments.
The Gitflow Workflow was first published in a highly regarded 2010 blog post from Vincent Driessen at nvie. The Gitflow Workflow defines a strict branching model designed around the project release. This workflow doesn’t add any new concepts or commands beyond what’s required for the Feature Branch Workflow. Instead, it assigns very specific roles to different branches and defines how and when they should interact.
The Forking Workflow is fundamentally different than the other workflows discussed in this tutorial. Instead of using a single server-side repository to act as the “central” codebase, it gives every developer a server-side repository. This means that each contributor has not one, but two Git repositories: a private local one and a public server-side one.
There is no one size fits all Git workflow. As previously stated, it’s important to develop a Git workflow that is a productivity enhancement for your team. In addition to team culture, a workflow should also complement business culture. Git features like branches and tags should complement your business’s release schedule. If your team is using task tracking project management software you may want to use branches that correspond with tasks in progress. In addition, some guidelines to consider when deciding on a workflow are:
The longer a branch lives separate from the production branch, the higher the risk for merge conflicts and deployment challenges. Short-lived branches promote cleaner merges and deploys.
Minimize and simplify reverts
It’s important to have a workflow that helps proactively prevent merges that will have to be reverted. A workflow that tests a branch before allowing it to be merged into the
master branch is an example. However, accidents do happen. That being said, it’s beneficial to have a workflow that allows for easy reverts that will not disrupt the flow for other team members.
Match a release schedule
A workflow should complement your business’s software development release cycle. If you plan to release multiple times a day, you will want to keep your
master branch stable. If your release schedule is less frequent, you may want to consider using Git tags to tag a branch to a version.