UData Implemented inPythonLicenceGNU Affero General Public License, version 3.0Kindsoftware engine, free software
Ultimate++ Implemented inC++Licence2-clause BSD LicenseKindwidget toolkit, integrated development environment, free software, application framework, rapid application development
VCMI LicenceGNU General Public License, version 2.0Appeared2007Kindgame engine, free software, source port, video game
Vimwiki Implemented inVimscriptLicenceMIT LicenseKindpersonal wiki software, plug-in, file format, free software
Vuex Implemented inJavaScript, TypeScriptLicenceMIT LicenseKindJavaScript framework, free software, JavaScript library
Wakanda Implemented inJavaScriptLicenceGNU General Public License, version 3.0, GNU Affero General Public LicenseKinddocument-oriented database management system, integrated development environment, database management system, proprietary software, free software
WebKit Licence2-clause BSD License, GNU Library General Public License, version 2.0 or laterKindfree software, browser engineDeveloperChris Dumez, Eric Seidel, Apple Inc., Darin Adler
Wiki.js Implemented inJavaScriptLicenceGNU Affero General Public License, version 3.0Kindfree software, wiki software
Wikibase Implemented inJavaScript, PHPLicenceGNU General Public License, version 2.0 or laterAppeared2012
WorldForge Implemented inC++LicenceGNU General Public License, version 2.0, GNU Lesser General Public License, GNU General Public License v3.0 or laterAppeared1998
Xash3D Implemented inCLicenceGNU General Public License, version 3.0Kindsoftware library, game engine, free software
YAML (Yet Another Multicolumn Layout) LicenceCreative Commons Attribution 2.0 GenericKindfree software, CSS frameworkLatest version4.1.2 (July 28, 2013)
Yew Implemented inRustLicenceApache Software License 2.0, MIT LicenseKindweb framework, free software
ZDoom LicenceGNU General Public License, version 2.0Kindfree software, source portBased onATB Doom, Linux Doom
ZK Implemented inJavaLicenceGNU Lesser General Public LicenseKindweb framework, Java software library, free software