Editing Microsoft Windows (section)

== Version control system ==
Up to and including every version before [[Windows 2000]], Microsoft used an in-house version control system named Source Library Manager (SLM). Shortly after Windows 2000 was released, Microsoft switched to a fork of Perforce named Source Depot.<ref>{{Cite web |last=Chen |first=Raymond |date=January 22, 2018 |title=The history of change-packing tools at Microsoft (so far) |url=https://devblogs.microsoft.com/oldnewthing/20180122-00/?p=97855 |url-status=live |archive-url=https://web.archive.org/web/20220525102009/https://devblogs.microsoft.com/oldnewthing/20180122-00/?p=97855 |archive-date=May 25, 2022 |access-date=September 2, 2023 |website=The Old New Thing |publisher=Microsoft Developer Blogs (DevBlogs)}}</ref> This system was used up until 2017 once the system could not keep up with the size of Windows.{{Citation needed|date=September 2023}} Microsoft had begun to integrate Git into [[Team Foundation Server]] in 2013,<ref>{{Cite web |last=Lewis |first=Andy |date=2013-06-26 |title=Visual Studio 2013 Preview: Git version control and Team Foundation Build |url=https://devblogs.microsoft.com/devops/visual-studio-2013-preview-git-version-control-and-team-foundation-build/ |access-date=2023-09-02 |website=Azure DevOps Blog |publisher=Microsoft Developer Blogs (DevBlogs) |language=en-US |archive-date=September 3, 2023 |archive-url=https://web.archive.org/web/20230903135727/https://devblogs.microsoft.com/devops/visual-studio-2013-preview-git-version-control-and-team-foundation-build/ |url-status=live }}</ref> but Windows (and Office) continued to rely on Source Depot.<ref>{{Cite web |last=Harry |first=Brian |date=2017-02-03 |title=Scaling Git (and some back story) |url=https://devblogs.microsoft.com/bharry/scaling-git-and-some-back-story/ |access-date=2023-09-02 |website=Brian Harry's Blog |publisher=Microsoft Developer Blogs (DevBlogs) |language=en-US |archive-date=September 3, 2023 |archive-url=https://web.archive.org/web/20230903135724/https://devblogs.microsoft.com/bharry/scaling-git-and-some-back-story/ |url-status=live }}</ref> The Windows code was divided among 65 different repositories with a kind of virtualization layer to produce unified view of all of the code.{{Citation needed|date=September 2023}}

In 2017 Microsoft announced that it would start using [[Git]], an open source version control system created by [[Linus Torvalds]], and in May 2017 they reported that the migration into a new Git repository was complete.<ref name="PBright" /><ref>{{Cite web |date=May 24, 2017 |title=The largest Git repo on the planet |url=https://devblogs.microsoft.com/bharry/the-largest-git-repo-on-the-planet/ |url-status=live |archive-url=https://web.archive.org/web/20211006233017/https://devblogs.microsoft.com/bharry/the-largest-git-repo-on-the-planet/ |archive-date=October 6, 2021 |access-date=October 8, 2021 |website=Brian Harry's Blog |language=en-US}}</ref><ref name=":0" />

=== VFSForGit ===
Each Git repository contains a complete history of all the files, which tends to be very large for Windows.<ref>{{Cite book |last1=Chacon |first1=Scott |last2=Straub |first2=Ben |date=2014 |title=Pro Git |publisher=Apress |others=The version found here has been updated with corrections and additions from hundreds of contributors. |isbn=978-1-4842-0077-3 |edition=2nd |chapter=2.1 Git Basics – Getting a Git Repository: Cloning an Existing Repository |chapter-url=https://git-scm.com/book/en/v2/Git-Basics-Getting-a-Git-Repository#_git_cloning |via=the Git Project |access-date=September 2, 2023 |archive-date=September 1, 2023 |archive-url=https://web.archive.org/web/20230901193044/https://git-scm.com/book/en/v2/Git-Basics-Getting-a-Git-Repository#_git_cloning |url-status=live }}</ref> Microsoft has been working on a new project called the [[Virtual File System for Git]] (VFSForGit) to address these challenges.<ref name=":0">{{Cite web |last=Bright |first=Peter |date=February 6, 2017 |title=Microsoft hosts the Windows source in a monstrous 300&nbsp;GB Git repository |url=https://arstechnica.com/information-technology/2017/02/microsoft-hosts-the-windows-source-in-a-monstrous-300gb-git-repository/ |url-status=live |archive-url=https://web.archive.org/web/20171226073905/https://arstechnica.com/information-technology/2017/02/microsoft-hosts-the-windows-source-in-a-monstrous-300gb-git-repository/ |archive-date=December 26, 2017 |access-date=December 26, 2017 |website=Ars Technica |df=mdy-all }}</ref>

In 2021 the VFS for Git was superseded by '''Scalar'''.<ref>{{Cite web |last=Stolee |first=Derrick |date=May 28, 2020 |title=Frequently Asked Questions: Why Are You Abandoning VFS for Git? |url=https://github.com/microsoft/VFSForGit/blob/3790eb06e14d88d71af11958414b59fd3cb2e65d/docs/faq.md#why-are-you-abandoning-vfs-for-git |website=GitHub |publisher=Microsoft |archive-date=May 1, 2023 |archive-url=https://web.archive.org/web/20230501123753/https://github.com/microsoft/VFSForGit/blob/3790eb06e14d88d71af11958414b59fd3cb2e65d/docs/faq.md#why-are-you-abandoning-vfs-for-git |url-status=live |access-date=2023-09-02 }}</ref>