How Git Rebase Works: Maintaining a Clean and Linear Project History

Git rebase is a powerful command that allows developers to maintain a clean and linear project history in their Git repositories. By incorporating the latest updates from the main branch into feature branches while keeping the branch’s history clean, rebase helps to create a more organized and manageable codebase. In this article, we will explore the inner workings of Git rebase and its various use cases.

Maintaining a Linear Project History

One of the primary reasons for using rebase is to maintain a clean and linear project history. When working on a feature branch, it is common for the main branch to progress with new commits. By rebasing the feature branch onto the latest commit of the main branch, developers can incorporate the latest changes while keeping the branch’s history linear and easy to follow. This approach allows for a seamless integration of the feature branch back into the main branch, resulting in a clean merge.

Two Options for Integrating Changes

When integrating changes from a feature branch into the main branch, developers have two options: merging directly or rebasing and then merging. Merging directly results in a 3-way merge and creates a merge commit that combines the changes from both branches. While this approach is suitable for many scenarios, it can lead to a more complex commit history with multiple merge commits.

On the other hand, rebasing facilitates a fast-forward merge, where the commits from the feature branch are applied directly on top of the latest commit in the main branch. This creates a perfectly linear history without any additional merge commits. By using rebase, developers can achieve a cleaner and more streamlined commit history.

Standard Rebase vs. Interactive Rebase

Git rebase can be used in two modes: standard mode and interactive mode. In standard mode, rebase automatically takes the commits from the current branch and applies them to the head of the specified branch. This straightforward approach is useful when you want to quickly incorporate changes from one branch into another.

In contrast, interactive rebase provides more control over the commit history. During an interactive rebase session, developers can alter individual commits, reorder them, combine multiple commits into one, or even discard commits entirely. This level of flexibility allows for a more fine-grained approach to managing the commit history.

Interactive Rebase Commands

When using interactive rebase, developers have access to various commands to manipulate commits. Here are some commonly used commands:

  • pick: Use commit as-is.
  • reword: Use commit but edit the commit message.
  • edit: Use commit but stop for amending.
  • squash: Combine the commit into the previous commit.
  • fixup: Similar to squash, but discards the commit’s log message.
  • exec: Run a command on each marked commit.
  • drop: Remove the commit.

These commands give developers granular control over the commit history, allowing them to refine and shape it according to their needs.

Handling Public History

While rebasing offers great flexibility in managing commit history, it is essential to exercise caution when dealing with public repositories. Once commits have been pushed to a public repository, it is generally advisable to avoid rebasing them. Replacing old commits with new ones can make it appear as if part of the project history abruptly vanished, causing confusion and potential issues for other collaborators.

It’s important to note that rebasing is best suited for local branches or feature branches that haven’t been shared with others yet. By rebasing before merging into the main branch, developers can ensure a clean and linear project history without disrupting the work of others.



In conclusion, Git rebase is a powerful tool for maintaining a clean and linear project history. By incorporating the latest updates from the main branch into feature branches, developers can keep their codebase organized and easily manageable. Whether using standard rebase or interactive rebase, understanding the commands and best practices associated with rebasing is crucial for effective Git workflow.

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FAQs

What is Git rebase?

Git rebase is a command in Git that allows you to integrate changes from one branch onto another. It is commonly used to maintain a clean and linear project history.

How does rebase differ from merging?

While merging combines the changes from two branches and creates a merge commit, rebase applies the commits from one branch on top of another branch, resulting in a linear history without additional merge commits.

What is the purpose of maintaining a linear project history?



Maintaining a linear project history makes it easier to follow the progression of commits and understand the development timeline. It provides a clean and organized view of the project’s evolution.

What are the two options for integrating changes using rebase?

When using rebase, you have two options: merging directly or rebasing and then merging. Merging directly creates a merge commit, while rebasing facilitates a fast-forward merge and a linear history.

What is the difference between standard rebase and interactive rebase?

In standard rebase, the commits from the current branch are automatically applied to the head of the specified branch. In interactive rebase, you have more control over the commit history, allowing you to alter individual commits, reorder them, or combine them into one.

What are some commonly used commands in interactive rebase?

During an interactive rebase session, you can use commands like pick, reword, edit, squash, fixup, exec, and drop. These commands help you modify and shape the commit history according to your requirements.

Can I rebase commits that have already been pushed to a public repository?



It is generally advised to avoid rebasing commits that have already been pushed to a public repository. Replacing old commits with new ones can cause confusion and disrupt the project history for other collaborators.

When should I use rebase in my Git workflow?

Rebase is most commonly used when working on feature branches or local branches. Before merging a feature branch into the main branch, rebasing allows you to incorporate the latest changes from the main branch and maintain a clean commit history.