Distributed version control

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Distributed version control systems such as Git and Mercurial have emerged in the last few years as a viable replacement for older centralized version control systems such as Subversion and Centralized Version Control (CVS). Git in particular has swept the open source community, becoming the revision control systems of some of the most important open source projects (e.g., the Linux kernel, Qt, Ruby on Rails).

Adoption

GitHub and BitBucket

GitHub.com was launched in 2008 as a hosting service for Git repositories. Improving upon many of the perceived flaws of older hosting services, GitHub has captured the vast majority of the Git hosting market share. GitHub's popularity has been partly responsible for the rising popularity of Git itself. BitBucket.org was also launched in 2008, offering a GitHub-like interface for Mercurial repositories. GitHub, BitBucket, and similar sites have swept the open source community, with many of the largest open source projects migrating to DVC and new DVC hosts simultaneously. Many of these new DVC hosts offer free public repositories for open source projects, charging only for private repositories.

Barriers to adoption

Support

Kiln

Auditing

git-svn

Platform support

Git, the most widely used DVC, was developed specifically for Linux kernel development. A Mac OS X port was achieved at a later date, but Windows lagged behind. Today Git can be run on Windows using Cygwin for POSIX emulation, or with the native msysGit can be run on Windows using Cygwin or native port called msysgit. Both these tools have greatly improved since their early releases, but the Git experience on Windows may still be behind Linux and Mac OS X. Mercurial and Bazaar do not suffer from the same platform fragmentation problems, probably owing to their multi-platform histories and largely Python (as opposed to C) implementations.

Development tool integration

Centralized systems like Subversion and CVS are widely used through graphical user interface (GUI) tools, especially in the Windows community. TortoiseSVN offers tight integration with Windows Explorer, and AnkSVN brings Subversion to Microsoft Visual Studio through a plugin. GUIs are also widely used in the Java community, the Subclipse and Subversive Eclipse plugins, for example. GUIs and IDE integration are standard for proprietary systems like Microsoft Visual SourceSafe or Team Foundation Server.

Many DVCs however were born from the Linux community which values GUIs and Integrated Development Environments (IDEs) rather less. Those accustomed to working with IDE GUI plugins may have difficulty transitioning to a terminal-based workflow. Efforts are ongoing to bring GUI support to the popular DVCs.

TortoiseHG has succeeded in replicating many of the ToirtoiseSVN features on Windows, but its GNOME (Linux) offerings less mature. An OS X port has not yet been released. JGit is a pure Java implementation of Git used by the Eclipse EGit plugin. EGit and JGit are officially supported by the Eclipse Foundation, so JGit-based plugins may become common in Java-based IDEs like Eclipse, NetBeans, and IntelliJ Idea. To date, however, these tools have not been widely used. Early versions were blamed for corrupting Git repositories, and they are not supported by GitHub.