Microsoft open-sources Windows Subsystem for Linux at Build 2025

At the ongoing Build 2025 event, Microsoft announced that Windows Subsystem for Linux (WSL) is now open source. This comes as the company also showed off big changes to Microsoft Edge and unveiled a Copilot coding agent for GitHub.

Now, Microsoft is opening up another major tool for developers—WSL. For the first time, developers can contribute directly to the Windows Subsystem for Linux. It’s available on GitHub under an open-source license. You can now submit pull requests and customize WSL to fit your own workflows.

Windows Subsystem for Linux is here for nearly a decade. It lets you use Linux command-line tools like bash, awk, and sed without leaving Windows or running a virtual machine. It’s especially handy in fields like data science and web development, where Linux-only tools are common.

If you’re new to Linux, WSL also a low-risk way to get comfortable with the command line. This isn’t the only open-source news from Build. Microsoft also open-sourced GitHub Copilot in Visual Studio Code, giving developers more control over how AI integrates with their tools.

Microsoft is showing it wants developers more involved. Whether it’s improving WSL, customizing Copilot, or building AI into web apps with new Edge APIs—this year’s Build is clearly about collaboration.