Microsoft has taken a major step with its Windows Subsystem for Linux (WSL), open-sourcing it and closing the oldest issue on the project’s GitHub repo.

WSL is an important component of Windows, giving developers and users the ability to run Linux apps and services from within Windows. WSL has become an important tool for both Microsoft and the Linux community. Windows developers gain access to valuable Linux tools, making it easier to developer cross platforms apps. At the same time, the Linux community benefits from that development, as well as more users being exposed to Linux and possibly making the switch from Windows full-time.

In a blog post, Microsoft’s Pierre Boulay announced the latest development.

Today we’re very excited to announce the open-source release of the Windows Subsystem for Linux. This is the result of a multiyear effort to prepare for this, and a great closure to the first ever issue raised on the Microsoft/WSL repo: Will this be Open Source? · Issue #1 · microsoft/WSL.

That means that the code that powers WSL is now available on GitHub at Microsoft/WSL and open sourced to the community! You can download WSL and build it from source, add new fixes and features and participate in WSL’s active development.

As Boulay says, the request to make WSL open source is the oldest issue raised on the project’s GitHub, raising the question as to why Microsoft waited till now to make the move. Boulay highlights WSL’s evolution, from adopting the main Linux kernel to adding GPU support, GUI application support, and support for systemd. The more Microsoft added to WSL’s abilities, the more it realized it needed to move faster.

A key element of that strategy is tapping into the community and the contributions it can make.

Over the years we’ve been incredibly lucky to have a strong community supporting WSL from day 1. We’ve been blessed with people sharing their knowledge, and spending countless hours to help track down bugs, find the best ways to implement new features and improve WSL.

WSL could never have been what it is today without its community. Even without access to WSL’s source code, people have been able to make major contributions that lead to what WSL is now.

This is why we’re incredibly excited to open-source WSL today. We’ve seen how much the community has contributed to WSL without access to the source code, and we can’t wait to see how WSL will evolve now that the community can make direct code contributions to the project.

Microsoft is on a roll with its commitment to Linux and open source. The company announced last week that it was making its open source Linux Integration Services Automation (LISA) tool available as a service via Azure Image Testing for Linux (AITL). The service is aimed at helping developers validate Linux images for use with Microsoft Azure.

Microsoft once had a reputation for aggressively protecting its Windows operating system from any threats. Under CEO Satya Nadella, the company has taken a decidedly different stance, instead focusing on making its apps and services work on as many platforms as possible. The company has also changed its stance on Linux, something its executives once described as a cancer. The company is now a major contributor to Linux kernel development and has its own Linux distro that helps power its cloud platform. Open-source WSL is simply the latest indication of Microsoft’s commitment to Linux.