Original author(s)Microsoft Research
Developer(s)Microsoft, 343 Industries
Initial releaseJanuary 2015; 9 years ago (2015-01)
Stable release
7.0.0 / November 8, 2022; 14 months ago (2022-11-08)[1]
Written inC#
Operating systemWindows, Linux, macOS
Platform.NET Framework,
TypeSoftware framework
LicenseMIT License

Orleans is a cross-platform software framework for building scalable and robust distributed interactive applications based on the .NET Framework[2][3] or on the more recent .NET.


Orleans was originally created by the eXtreme Computing Group at Microsoft Research[2] and introduced the Virtual Actor Model as a new approach to building distributed systems for the cloud. Orleans scales from a single on-premises server to highly-available and globally distributed applications in the cloud.[4]

Starting with cloud services for the Halo franchise, the framework has been used by a number of cloud services at Microsoft[5] and other companies since 2011.[6] The core Orleans technology was transferred to 343 Industries and is available as open source since January 2015.[7] The source code is licensed under MIT License and hosted on GitHub.[8]

Orleans runs on Microsoft Windows, Linux, and macOS and is compatible with .NET Standard 2.0 and above.[9]


Some Orleans features include:[10]

Related implementations

The Electronic Arts BioWare division created Project Orbit. It is a Java implementation of virtual actors that was heavily inspired by the Orleans project.[13][14]

See also


  1. ^ "Tags · dotnet/orleans · GitHub". GitHub Orleans repository. Retrieved 2022-11-09.
  2. ^ a b Microsoft's Orleans Distributed App Framework Is Now Cross Platform - The New Stack
  3. ^ Open-Source Cloud Framework By Microsoft - HPC ASIA
  4. ^ Microsoft to release Project Orleans as open source | Computerworld
  5. ^ Orleans at Microsoft | .NET Conf 2020
  6. ^ Microsoft opens early adopter program for its 'Orleans' cloud framework | ZDNet
  7. ^ Microsoft to make Halo 4 gaming cloud engine Project Orleans open source - SiliconANGLE
  8. ^ "Dotnet/Orleans". GitHub. 17 February 2022.
  9. ^ "Orleans benefits". learn.microsoft.com.
  10. ^ "Introduction | Microsoft Orleans Documentation". Archived from the original on 2020-08-06. Retrieved 2019-11-01.
  11. ^ Resurrecting Middle-Tier Distributed Transactions | Microsoft Research
  12. ^ Distributed Transactions are dead, long live distributed transactions! | Reactive Summit 2018
  13. ^ "Home · orbit-legacy/Orbit1 Wiki". GitHub.
  14. ^ Gamasutra: Creating scalable backends for games using open source Orleans framework

Further reading