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RunUO Git Repository

RunUO is no longer officially supported by a core team.

If you wish to find support in a wider UO development commuity, visit ServUO - Ultima Online Emulation

Typical Windows Build

PS C:\runuo> C:\Windows\Microsoft.NET\Framework64\v4.0.30319\csc /optimize /unsafe /t:exe /out:RunUO.exe /win32icon:Server\runuo.ico /d:NEWTIMERS /d:NEWPARENT /recurse:Server\*.cs

Typical Linux Build (MONO)

~/runuo$ mcs -optimize+ -unsafe -t:exe -out:RunUO.exe -win32icon:Server/runuo.ico -nowarn:219,414 -d:NEWTIMERS -d:NEWPARENT -d:MONO -reference:System.Drawing -recurse:Server/*.cs

zlib is required for certain functionality. Windows zlib builds are packaged with releases and can also be obtained separately here:

RunUO supports Intel's hardware random number generator (Secure Key, Bull Mountain, rdrand, etc). If rdrand32.dll/rdrand64.dll are present in the base directory and the hardware supports that functionality, it will be used automatically. You can find those libraries here:

Latest Razor builds can be found at

Latest UOSteam builds (previously AssistUO) can be found at