The Ruby License is a Free and Open Source license applied to the

Ruby programming language Ruby is an interpreted, high-level, general-purpose programming language which supports multiple programming paradigms. It was designed with an emphasis on programming productivity and simplicity. In Ruby, everything is an object, including p ...

and also available to be used in other projects. It contains an explicit

dual licensing Multi-licensing is the practice of distributing software under two or more different sets of terms and conditions. This may mean multiple different software licenses or sets of licenses. Prefixes may be used to indicate the number of licenses ...

clause, stating that software subject to its terms may be distributed under either the terms included the Ruby License itself or under those of either the

GNU General Public Licence The GNU General Public License (GNU GPL or simply GPL) is a series of widely used free software licenses that guarantee end users the four freedoms to run, study, share, and modify the software. The license was the first copyleft for general u ...

v2, or the two-clause BSD License (depending on the version of the Ruby License used). The license is typically considered to be a

free software license A free-software license is a notice that grants the recipient of a piece of software extensive rights to modify and redistribute that software. These actions are usually prohibited by copyright law, but the rights-holder (usually the author) ...

due to the presence of the dual-licensing clause.

History

For versions up to 1.9.2, the Ruby programming language was available under an explicit dual-licence scheme which allowed users to choose between a dedicated Ruby licence or the

v2 (GPLV2), which is one of the most common free software licences. Starting at version 1.9.3, the dual-licensing clause changed to offer the choice of the

FreeBSD License BSD licenses are a family of permissive free software licenses, imposing minimal restrictions on the use and distribution of covered software. This is in contrast to copyleft licenses, which have share-alike requirements. The original BSD lice ...

Compatibility

The Ruby License has unusual

copyleft Copyleft is the legal technique of granting certain freedoms over copies of copyrighted works with the requirement that the same rights be preserved in derivative works. In this sense, ''freedoms'' refers to the use of the work for any purpose ...

requirements, stating that redistributions should not necessarily be under the terms of the Ruby license, but placed "in the

Public Domain The public domain (PD) consists of all the creative work to which no exclusive intellectual property rights apply. Those rights may have expired, been forfeited, expressly waived, or may be inapplicable. Because those rights have expired, ...

or otherwise Freely Available". For example, a modified form of a program licensed under the Ruby license may be placed under the

, which is a non copyleft license. The Ruby License is approved by the

Free Software Foundation The Free Software Foundation (FSF) is a 501(c)(3) non-profit organization founded by Richard Stallman on October 4, 1985, to support the free software movement, with the organization's preference for software being distributed under copyleft (" ...

and is considered compatible with the GNU General Public License, due to its explicit

dual-licensing Multi-licensing is the practice of distributing software under two or more different sets of terms and conditions. This may mean multiple different software licenses or sets of licenses. Prefixes may be used to indicate the number of licenses ...

clause. The

Open Source Initiative The Open Source Initiative (OSI) is the steward of the Open Source Definition, the set of rules that define open source software. It is a California public-benefit nonprofit corporation,_with_501(c)(3).html" ;"title="110. - 6910./ref> is a type o ...

does not explicitly include the Ruby license as a certified an open source license; this is considered "unnecessary" due to the dual licensing clause. In discussion over the change of the dual licensing clause on the debian-legal mailing list, it was noted that while the Ruby license itself is arguably not compatible with the

Debian Free Software Guidelines The Debian Free Software Guidelines (DFSG) is a set of guidelines that the Debian Project uses to determine whether a software license is a free software license, which in turn is used to determine whether a piece of software can be included in De ...

, this is unimportant due to the dual-licensing clause. Software under Ruby license (including the older version when GPLv2 was a listed alternative Ruby 1.9.2 license) may be included in binary form within an Apache product if the inclusion is appropriately labeled.

Adoption

Software other than the

itself which uses the Ruby License includes: *

JRuby JRuby is an implementation of the Ruby programming language atop the Java Virtual Machine, written largely in Java. It is free software released under a three-way EPL/GPL/ LGPL license. JRuby is tightly integrated with Java to allow the embeddin ...

, an implementation of Ruby atop the Java Virtual Machine *

MacRuby MacRuby is a discontinued implementation of the Ruby language that ran on the Objective-C runtime and CoreFoundation framework under development by Apple Inc. which "was supposed to replace RubyCocoa". It targeted Ruby 1.9 and used the high per ...

, an implementation of Ruby 1.9 directly on top of Mac OS X core technologies such as the Objective-C runtime and garbage collector, the LLVM compiler infrastructure and the Foundation and ICU frameworks. MacRuby contains code from the Ruby project and the source code of the most MacRuby examples, unless specified, are covered by the Ruby license. *

RubyGems RubyGems is a package manager for the Ruby programming language that provides a standard format for distributing Ruby programs and libraries (in a self-contained format called a "gem"), a tool designed to easily manage the installation of gems ...

, a package manager for Ruby *

IronRuby IronRuby is an implementation of the Ruby programming language targeting Microsoft .NET Framework. It is implemented on top of the Dynamic Language Runtime (DLR), a library running on top of the Common Language Infrastructure that provides dynam ...

, an implementation of Ruby targeting the

.NET Framework The .NET Framework (pronounced as "''dot net"'') is a proprietary software framework developed by Microsoft that runs primarily on Microsoft Windows. It was the predominant implementation of the Common Language Infrastructure (CLI) until bein ...

* The JSON implementation for Ruby

References

{{refs

External links

Text
of the Ruby License Ruby (programming language) Free and open-source software licenses