Question: What web resource includes both the X-Ray Engine source code and allows collaboration features such as bug tracking and feature requests?

Context paragraphs:
Amazon Lumberyard: Amazon Lumberyard is a free cross-platform triple-A game engine developed by Amazon and based on the architecture of CryEngine, which was licensed from Crytek in 2015.  The engine features integration with Amazon Web Services to allow developers to build or host their games on Amazon's servers, as well as support for livestreaming via Twitch.  Additionally, the engine includes Twitch ChatPlay, where viewers of the Twitch stream can influence the game through the associated chat, a method of play inspired by the "Twitch Plays Pokémon" phenomenon.  The source code is available to end users with limitations: users may not publicly release the Lumberyard engine source code or use it to release their own game engine.  Lumberyard launched on February 9, 2016 alongside GameLift, a fee-based managed service for deploying and hosting multiplayer games, intended to allow developers to easily develop games that attract "large and vibrant communities of fans."  s of February 2017 , the software is currently in beta and can be used to build games for Microsoft Windows, PlayStation 4, Xbox One, with limited support for iOS and Android, and support for Linux and Mac coming as well.  Virtual reality integration was added in Beta 1.3, allowing developers to build games supporting devices like Oculus Rift and HTC Vive.

Comparison of source code hosting facilities: A source code repository is a file archive and web hosting facility where a large amount of source code, for software or for web pages, is kept, either publicly or privately.  They are often used by open-source software projects and other multi-developer projects to handle various versions.  They help developers submit patches of code in an organized fashion.  Often these web sites support version control, bug tracking, release management, mailing lists, and wiki-based documentation.

Uniform Resource Characteristic: In computer science, a Uniform Resource Characteristic (URC) is a string of characters representing the metadata of a Uniform Resource Identifier (URI), a string identifying a Web resource).  A URC binds a URI's associated Uniform Resource Name (URN), a unique name for a Web resource) to its Uniform Resource Locator (URL), the location at which a Web resource can be found).  URCs were proposed as a specification in the mid-1990s, but were never adopted.

Backlink: A backlink for a given web resource is a link from some other website (the referrer) to that web resource (the referent).  A "web resource" may be (for example) a website, web page, or web directory.

GitHub: GitHub is a web-based Git or version control repository and Internet hosting service.  It is mostly used for code.  It offers all of the distributed version control and source code management (SCM) functionality of Git as well as adding its own features.  It provides access control and several collaboration features such as bug tracking, feature requests, task management, and wikis for every project.

X-Ray Engine: The X-Ray Engine is the name of the 3D game engine created by Kiev-based computer game developer GSC Game World.  Released on 20 March 2007, the engine is used in the first three S.T.A.L.K.E.R. games released by the company.  An upgraded engine was planned for the cancelled game "S.T.A.L.K.E.R. 2".  In August 2014 the engine's source code version 1.5.10 became available on GitHub under a non-open-source license.

Source code virus: Source code viruses are a subset of computer viruses that make modifications to source code located on an infected machine.  A source file can be overwritten such that it includes a call to some malicious code.  By targeting a generic programming language, such as C, source code viruses can be very portable.  Source code viruses are rare, partly due to the difficulty of parsing source code programmatically, but have been reported to exist.

Web annotation: A web annotation is an online annotation associated with a web resource, typically a web page.  With a Web annotation system, a user can add, modify or remove information from a Web resource without modifying the resource itself.  The annotations can be thought of as a layer on top of the existing resource, and this annotation layer is usually visible to other users who share the same annotation system.  In such cases, the web annotation tool is a type of social software tool.  For Web-based text annotation systems, see Text annotation.

JIRA Studio: JIRA Studio was an integrated, hosted software development suite developed by Atlassian Software Systems.  JIRA Studio included Subversion for revision control, JIRA for issue tracking and bug tracking, Confluence for content management, JIRA Agile (previously known as GreenHopper) for agile planning and management, Bamboo for continuous integration, Crucible for code review and FishEye for source code repository browsing.

PhpDocumentor: phpDocumentor is an open source documentation generator written in PHP.  It automatically parses PHP source code and produces readable API and source code documentation in a variety of formats.  phpDocumentor generates documentation based on PHPDoc-formatted comments and the structure of the source code itself.  It supports documentation of both object-oriented and procedural code.  phpDocumentor can create documentation in HTML, PDF, CHM or Docbook formats.  It can be used from the command line or via a web interface.  It has support for linking between documentation, incorporating user level documents like tutorials, and creation of highlighted source code with cross referencing to PHP general documentation.  phpDocumentor is able to parse all PHP syntax and supports PHP4 and PHP5, although legacy phpDocumentor 1.4.4 does not support all features of PHP 5.3.  It is an open source project and is distributed under the terms of the GNU Lesser General Public License (LGPL).

Supporting paragraphs: X-Ray Engine GitHub
Answer: GitHub