Microsoft and Open Source: An unofficial timeline
The profound cultural transformation towards open source did not happen overnight at Microsoft. This is an unofficial timeline of Microsoft's embrace of open source.
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The profound cultural shift towards open source did at Microsoft was the result of sustained efforts within the company by open source advocates. Microsoft's shift is a model for positively transforming organizations. It is also a testament to the power of collaboration in technology. After Build 2020 it is now clear Microsoft is a Linux and open source company.
This is a very brief timeline of Microsoft's evolution into an open source leader. It is an attempt to provide historical context of a two-decades-long process. An open source version of this post is maintained on GitHub.
This is not endorsed by Microsoft, Canonical, or any person, company, or project mentioned here.
Timeline
2002
- Microsoft begins experimenting with 'shared source', including SSCLI, the core of .NET
2004
- WiX, the first project from Microsoft under an OSS approved license, is released
- Begins cross-licensing software patents with Linux vendors
2005
- F# released under the Apache 2.0 license
2006
- CodePlex announced
- Ports PHP to Windows, upstreams code under PHP license
- Partners with Novell to improve open source interoperability
2007
- Open Source Initiative approves the Microsoft Public License (MS-PL) and Microsoft Reciprocal License (MS-RL)
- Provides access to Windows NT kernel source for research to universities
- Open sources IronRuby and IronPython under Microsoft Public License
- Open sources xunit under Microsoft Public License
- Reaches agreement with EU to reduce costs of licensing patents and specifications
- Scheduled to exit US DOJ antitrust oversight, voluntarily agrees to extended oversight
2008
- Forms Open Web Foundation with Google, Facebook, Sun, IBM, Apache, and others
- Joins Apache Software Foundation
- Releases source for Singularity, an experimental OS to CodePlex
- Begins distributing the open source jQuery JavaScript library with Visual Studio
- Acquires Powerset, it's first open source acquisition, upstreams code from HBase to Apache Hadoop
2009
- Begins contributing to Linux kernel
- Forms independent CodePlex Foundation, later known as Outercurve Foundation to promote open source
- Open sources ASP.NET MVC under the Microsoft Public License
- Apologizes after download on website is found to have GPL code, properly open sources download
- Promises not to enforce patents against open source implementations of C#, e.g. Mono
- Settles a dispute with TomTom over FAT32 software patents, avoiding further conflict with open source
- Reaches settlement with EU to provide users a choice of web browsers on Windows installation
- Platform Strategy Group begins an internal push for embracing open source
- "Burning the Ships: Transforming Your Company's Culture Through Intellectual Property Strategy" is published on Microsoft's embrace of open collaboration
- "Has Microsoft lost its war on open source?" InfoWorld
2010
- Signs Joomla! Contributor Agreement and upstreams improvements
- Relicenses IronRuby and IronPython under Apache License 2.0
- "Microsoft: 'We love open source'" Network World
2011
- Acquires Skype, maintains Linux client
- Begins contributing code to Samba
- Exits antitrust oversight by US DOJ
- Ports Node.js to Windows, upstreams code under Apache 2.0
- 📰 "Microsoft Embraces Elephant of Open Source" Wired
2012
- Azure begins hosting Linux virtual machines
- Codeplex supports git
- Begins contributing to git and collaborates with GitHub on LibGit2
- Ports Apache Hadoop to Windows, upstreams code under MIT
- Open sources ASP.NET, MCV, Razor, and Web API under Apache 2.0
- Open sources React Extensions and IL2JS under Apache 2.0
- Forms Microsoft Open Technologies, Inc.
- Releases TypeScript under Apache 2.0, first Microsoft project on GitHub
- Canonical closes Ubuntu bug #1
- 📰 "Microsoft opens up" O'Rielly
2013
- Steve Ballmer resigns
- VM Depot announced, community-driven repository of Linux and BSD virtual machines for Azure
- Microsoft challenges broad US warrant for overseas e-mails and helps create a new law improving e-mail privacy
- xunit transferred to Outercurve Foundation, relicensed under Apache 2.0
- 📰 "Microsoft's Open Source Company Is a Year Old. But What Is It?" Wired
2014
- Satya Nadella appointed CEO
- The full .NET stack, Microsoft's flagship development toolkit, is open sourced and contributed to .NET Foundation
- Implements AllJoyn support in Windows, contributes code upstream
- Creates official GitHub presence
- Releases Wireless Display Adapter, first hardware device to use embedded Linux
- Contributes to OpenJDK
- "Microsoft loves Linux." - Satya Nadella
- 📰 "More open-source at Microsoft? You'd better believe it" VentureBeat
2015
- Visual Studio Code released, releases Linux build
- Co-founds Node.js Foundation
- Joins R Foundation
- Forms Open Source Programs Office, tasked with enabling and normalizing open source across the company
- Open sources Matter Center, Microsoft's legal practice management software
- Open sources Chakra, legacy Microsoft Edge’s JavaScript engine
- 📰 "How Open Source Is Shaping Microsoft's Future" RedmondMag
2016
- Windows Subsystem for Linux announced in partnership with Canonical
- Joins Linux Foundation
- Open sources PowerShell, releases Linux build
- Begins porting Sysinternals to Linux
- Acquires Xamarin, relicenses Mono under MIT license
- Acquires LinkedIn, maintains Apache Kafka as open source
- SQL Server released for Linux
- Begins hosting Linux Foundation courses on edX
- SONiC released, based on Debian GNU/Linux
- Begins opening Reactors worldwide for use by entrepreneurs and open source communities
- "The company has become an enthusiastic supporter of Linux and of open source and a very active member of many important projects." - Jim Zemlin, Executive Director of The Linux Foundation
- 📰 "Why Microsoft is turning into an open-source company" ZDNet
2017
- Satya Nadella releases "Hit Refresh: The Quest to Rediscover Microsoft's Soul and Imagine a Better Future for Everyone" describing his vision for an open and collaborative Microsoft
- Forms Open Source Programs
- Joins Open Source Initiative
- Joins Cloud Native Computing Foundation
- Joins MariaDB Foundation
- Acquires Deis
- Open sources Git Virtual File System (GVFS), the work done moving Windows to git
- Opens Microsoft Store to open source applications
- Better privacy controls, privacy dashboard, and diagnostic data transparency introduced in Windows
- Announces Linux development with C++ in Visual Studio
- Gives keynote at Open Source Summit North America
- Moves Windows development to git
- 📺 Microsoft Loves Open Source: Becoming the Largest Contributor - GitHub Universe 2017
- 📰 "How Microsoft Is Shifting Focus to Open Source" The New Stack
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2018
- Joins Open Innovation Network, cross-licenses 60,000 patents with open source community
- Acquires GitHub
- "We are all in on open source." - Satya Nadella
- GitHub Actions is released, providing free CI/CD for open source projects
- Windows Subsystem for Linux 2 announced powered by Linux kernel
- Begins using Citus and PostgreSQL on Ubuntu to analyze telemetry from Windows test builds on employee devices
- PowerShell released as a snap
- OpenSSH included in Windows
- Shifts their mobile application strategy to Android, begins contributing to Android developer ecosystem
- Windows Calculator released as open source
- 📰 "Microsoft may be the world's largest open source contributor" TechRepublic
2019
- Visual Studio Code released as a snap
- GitHub announces GitHub Sponsors, lowers prices
- Edge browser released based on open source Chromium
- Linux surpasses Windows usage on Azure
- Begins adopting open source-style collaboration internally
- Teams released for Linux
- Acquires Citus Data, maintains open source project
- Joins OpenChain
- Admitted to Linux-distros security mailing list
- Files amicus brief at the US Supreme Court in support of open source and Linux
- Creates Open Application Model with Alibaba Cloud as a Open Web Foundation project
- Releases new Windows Terminal and PowerToys as open source
- Published exFAT as open specification, contributes patents to OIN, and upstreams driver to Linux kernel
- Stores all public GitHub repos for 1,000 years in Svalbard, Norway
- Joins Unified Patents Open Source Zone to defend open source from patent trolls
- Announces Android-based smartphone, Surface Duo, with a Linux kernel
- Announces Microsoft Defender for Linux
- Open sources SPTAG, a crucial search algorithm used by Microsoft
- Open sources SandDance, a data visualization tool
- Open sources the Microsoft C++ Standard Library
- Open sources Interpret ML
- Open sources Quantum Development Kit, a quantum computing SDK
- Satya Nadella speaks at Red Hat Summit
- Richard Stallman speaks at Microsoft, states "we should not maintain a burning grudge over actions that ended years ago"
- Linux Torvalds quoted at Linux Plumbers Conference as saying Microsoft "have changed"
- JS Foundation and Node.js Foundation merge to form OpenJS Foundation, Microsoft contributes Electron to OpenJS Foundation
- Scott Hanselman gives keynote at NDC London laying out Microsoft's open source vision
- 📰 "Microsoft: The open source company" Ars Technica
2020
- Acquires npm, the Node package manager
- Hosts WSLConf, the first conferenced dedicated to WSL
- Microsoft president Brad Smith admits being wrong about open source
- Edge browser port to Linux seen at Build
- Pushes improvements to Chromium upstream
- Releases open source Windows Package Manager
- Open sources dataset to help fight COVID-19-related cybersecurity threats
- Open sources Java extension for SQL Server
- Open sources MSQuic, a Windows NT kernel library for QUIC
- Open sources Petridish, a neural architecture search algorithm for deep learning
- Open sources Project Rocket, a software stack to perform live video analysis by AI/ML
- Open sources Project Bonsai, a machine teaching service
- Open sources Application Inspector, cross-platform source code security analyzer
- Open sources TensorWatch, a debugging tool for AI and deep learning
- Open sources Project Verona, a memory-safe research language
- Upstreams open source improvements to QNNX natural language model
- Linux-based Azure Sphere OS released
- Announces plans to open source Fluid Framework
- Announces Python for Excel
- Ad features Ubuntu on Surface Book 3
- 📰 "Microsoft’s romance with open source software is on display at Build 2020" Ars Technica
Known Open Source Collaborations
- Canonical
- Red Hat
- SuSE
- Debian
- IBM
- Oracle
- Chef
- Puppet
- Redis Labs
- Elastic
- Samsung
- Cloudera
- Docker
- Nokia
- HashiCorp
- PostgreSQL
- Kali Linux
- Whitewater Foundry
- Allianz
- React
- Flutter
- HashiCorp
- Nvidia
- BMW
- Apache Cassandra
- Apache Kafka
- Apache Hadoop
- Apache Spark
- Linux Foundation
- Cloud Native Computing Foundation
- Eclipse Foundation
- OpenDaylight
- Open Container Initiative
- R Consortium
- F# Foundatoin
- .NET Foundation
- Open API Initiative
- Confidential Computing Consortium
- OpenChain
- TODO Group
- Open Source Initiative
- Apache Software Foundation
- iZootoo
- Linux Containers on Windows
- Azure Arc
- Azure Databricks
- Azure Linux virtual machines
- Azure Linux containers
- Azure-tuned Linux kernel
- Azure Spring Cloud
- Azure DevOps
- Azure HDinsight
- GitHub Actions
- Microsoft Defender for Linux
- StorSimple
Select Open Source Projects
The list below is incomplete. opensource.microsoft.com current lists 1,155 open source projects at Microsoft and it would not be possible to curate them all here.
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Here is a list of selected projects:
Dev Tools
.NET
- .NET Project
- Roslyn - .NET Compiler
- MSBuild
Web Dev Tools
- Edge dev tools
- Playwright - Node library to automate Chromium, Firefox and WebKit with a single API
- Blazor
AI/ML/Robotics
- Project Moab
- TensorWatch - A debugging and visualization tool designed for data science, deep learning and reinforcement learning
- Light Gradient Boosting Machine
- CNTK - A unified deep learning toolkit
- AirSim - Open source simulator for autonomous vehicles built on Unreal Engine / Unity
Database
Cloud
- Azure CLI
- Open Enclave SDK - A hardware-agnostic open source library for developing applications that utilize hardware enclaves.
Games
Windows
Other
- WorldWide Telescope - A visualization environment that brings together imagery from the world's best ground- and space-based telescopes
- Project Mu - The UEFI core used in Microsoft Surface and Hyper-V
Programming Languages
- TypeScript - Programming language similar to JavaScript, among the most popular on GitHub
- Bosque - An experiment in regularized design for a machine assisted rapid and reliable software development lifecycle
- Verona - Research programming language for concurrent ownership
- SPTAG - A library for fast approximate nearest neighbor search
- P - A language for asynchronous event-driven programming
More Open Source at Microsoft
- Organization page on GitHub
- Open Source Program Group
- Open Source Partner Network
- Open Source Blog
- Command Line Blog
- Open Specification Promise
Historic Open Source Contributions
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