What is source code management?
Source code management (SCM) is the process of tracking, organizing, and managing changes to source code and other project files. It gives development teams a record of changes, making it easier to collaborate, review work, resolve conflicts, and return to an earlier version when needed.
SCM is closely associated with version control, which records different versions of files over time. Teams use source code management systems to maintain a shared source of truth while multiple developers and other contributors work on the same project.
Most SCM workflows include features such as version history, branching, merging, and conflict resolution. These tools help teams work on changes independently and combine their work without accidentally overwriting one another.
How does source code management work?
Source code management (SCM) systems track changes to a project’s source code and other files over time, allowing multiple contributors to work from a shared repository, often called a “repo.”
A typical SCM workflow includes:
- Create a branch: A developer creates a separate branch to work on a feature or fix without changing the main codebase.
- Make changes: The developer modifies files and tests the changes locally.
- Commit changes: The developer records a set of related changes in a commit, creating a point in the project’s version history.
- Review and merge: Changes can be reviewed and then merged into the main branch when they are ready.
- Resolve conflicts: When changes to the same parts of a file cannot be combined automatically, contributors resolve the conflict before merging.
- Restore earlier versions: The version history makes it possible to inspect previous changes or restore an earlier version when needed.
This workflow lets teams work on the same project simultaneously while maintaining a record of how the codebase has changed. It also makes it easier to identify when a bug was introduced and understand which changes contributed to it.
How is source code management used?
Source code management is used to help teams work on the same project while keeping track of changes and maintaining a reliable version history. Common SCM workflows include:
- Branching: Contributors create separate branches to work on features, fixes, or experiments without changing the main branch.
- Testing and review: Changes can be tested and reviewed independently before they are added to the main project.
- Merging: Once changes are ready, a branch can be merged into the main branch so the rest of the team can use the updated code.
- Conflict resolution: When changes to the same files cannot be combined automatically, contributors resolve the conflicts before completing the merge.
- Version history: SCM records previous versions and changes, making it easier to identify when an issue was introduced or restore an earlier version.
- Remote collaboration: Repositories can be hosted on remote servers, allowing distributed teams to share changes and collaborate across locations.
For game development, SCM can also manage large project files and binary assets, such as textures, models, audio, and other files that are not handled like traditional source code. File-based workflows can allow contributors to work with individual project files rather than repeatedly transferring an entire project.
Unity's source code management solutions support version control workflows for programmers and artists, including branching and collaboration on large repositories and binary files.
How do I get started with source code management tools?
The best time to introduce source code management is before a project becomes difficult to manage, rather than waiting until the team is already dealing with conflicting changes or lost work. Introducing SCM early also gives the team time to establish a consistent workflow.
When evaluating an SCM tool, consider:
- File types and sizes: Make sure the system can handle the source code and project assets your team works with, including large binary files.
- Team workflows: Choose a tool that works for everyone contributing to the project, including programmers, artists, designers, and other collaborators.
- Branching and merging: Check how easily your team can create branches, review changes, merge work, and resolve conflicts.
- Collaboration: Consider whether the tool supports the way your team works across locations and time zones.
- Security: Review access controls, permissions, and how project data is stored and shared.
- Cost: Compare pricing with the size of your team, repository requirements, and features you need.
- Flexibility: Look for a workflow that can adapt as the project and team grow.
For more guidance, see Unity's guide to choosing a version control tool.
What are the benefits of source code management?
Source code management helps teams collaborate on projects while maintaining control over changes and version history. Key benefits include:
- Better collaboration: Programmers, artists, designers, and other contributors can work on different parts of a project without accidentally overwriting one another’s changes.
- Version history: Teams can review previous changes, identify when issues were introduced, and restore earlier versions when needed.
- Safer experimentation: Branching lets contributors develop and test features independently before merging them into the main project.
- Conflict management: SCM tools help teams identify and resolve conflicting changes when multiple contributors edit the same files.
- Centralized project history: A shared repository provides a consistent record of project changes, making it easier for teams to understand what changed and why.
What are the challenges of source code management?
While source code management helps teams work more efficiently, it also introduces challenges that teams need to account for when choosing and implementing an SCM system.
- Learning curve for non-technical teammates: Artists and designers who are new to branching and merging may need onboarding before they can contribute confidently.
- Merge conflicts require human judgment: SCM tools can identify conflicting changes, but resolving them correctly still requires someone to understand what each change does.
- Large binary files can be challenging: Game projects often contain large art, audio, and other binary assets, so teams need an SCM tool designed to handle these files efficiently.