By now, we probably don't have to tell you that GitHub is a big deal. The site is the home to more than 4.5 million open source projects, letting software coders share and collaborate on software code, and sometimes, people share other stuff too.

But Atlassian – the Australian company behind popular developer tools like JIRA – wants in on this game too. Atlassian already owns GitHub competitor BitBucket and sells a product called Stash, which competes with GitHub Enterprise by letting companies build their own private GitHub-style code repositories on their own servers. Now the company is rolling out a tool that will compete with GitHub's Windows client: SourceTree, a visual tool for working with GitHub, BitBucket, Stash or any other code repository based on the code-management tools Git or Mercurial.

SourceTree has long been available for Macintosh OS X, but as of Tuesday, Windows developers can download the public beta.

It's another example of GitHub and Git finally getting more love on Microsoft's Windows operating system. Earlier this year, Microsoft integrated support for Git into Microsoft Visual Studio using a set of open source libraries the software company is helping to develop.

GitHub is powered by a code-version-control tool called Git, which was created by Linus Torvalds, better known as the creator of Linux. And since it was designed for Linux developers, it's only really ever been supported on Unix-style operating systems like Linux and OS X. While those platforms are enormously popular with developers, there are still legions of Microsoft Windows developers out there, and they like to play with open source too.

SourceTree doesn't actually include its own Git implementation. Instead, it will use whatever version of Git a developer already has installed. If none is found, SourceTree will install the version of Git developed for the MinGW Unix-like environment for Windows. The issue that SourceTree is really trying to address is the notorious difficulty of using Git from the command line. There are several other projects trying to solve this same problem, including TortoiseGit and Git-Cola.