Pelican Implemented inPythonLicenceGNU Affero General Public License, version 3.0Kindfree software, static site generator
Phonon Implemented inC++LicenceGNU Lesser General Public License, version 2.1Kindmultimedia framework, free software
Plone Implemented inPythonLicenceGNU General Public License, version 2.0Kindcontent management system, web framework, free software
PrBoom LicenceGNU General Public License, version 2.0 or laterKindfree software, source portBased onBoom
ProcessWire Implemented inPHPLicenceMozilla Public LicenseKindcontent management system, web framework, free software
PsDooM LicenceGNU General Public License, version 2.0Kindfree software, source portDeveloperDennis L Chao
PukiWiki Implemented inPHPLicenceGNU General Public License, version 2.0 or later, GNU General Public LicenseKindfree software, wiki software
Pyjs Implemented inPythonLicenceApache Software License 2.0Kindwidget toolkit, web framework, free software
Pylons Implemented inPythonLicence3-clause BSD LicenseKindweb framework, Python package, free software
Pyramid Implemented inPythonLicenceRepoze Public LicenseKindweb framework, Python package, free software
Python-Ogre Implemented inPythonLicenceGNU Lesser General Public LicenseKindsoftware library, game engine, free software
Qooxdoo Implemented inJavaScriptLicenceGNU Lesser General Public LicenseKindsoftware library, JavaScript framework, free software, JavaScript library
Qt Implemented inC++LicenceGNU General Public License, version 3.0, GNU General Public License, version 2.0, GNU Lesser General Public License, version 3.0Appeared1995
Selenium Implemented inJavaLicenceApache Software License 2.0Kindsoftware library, Java software library, test environment, free software, free and open-source software, test automation framework
Semantic UI Implemented inJavaScriptLicenceExpat licenseKindfree software, CSS framework, JavaScript library
Shark Framework LicenceGNU Lesser General Public LicenseKindfree softwareLatest version2.13.1 (May 26, 2015)
Spatterlight LicenceGNU General Public License, version 3.0Kindinteractive fiction interpreter, free softwareLatest version1.5.5 (October 18, 2026)
Spring Framework Implemented inJava, Kotlin, Apache GroovyLicenceApache Software License 2.0Appeared2002
Stratagus Implemented inC++LicenceGNU General Public License, version 2.0Kindgame engine recreation, free software
Taganak SDK Implemented inRustLicenceGNU Lesser General Public License, version 2.1 or laterAppeared2024
Tailwind CSS Implemented inJavaScript, Cascading Style Sheets, Rust, TypeScriptLicenceMIT LicenseAppeared2019
Tamarin Implemented inC++LicenceGNU Lesser General Public License, Mozilla Public License, version 2.0, GNU General Public LicenseKindvirtual machine, free software, JavaScript engine
TamTam LicenceGNU General Public License, version 2.0Kindfree software, wiki softwareDeveloperMarcell Mars, Aleksandar Erkalović
TCPDF Implemented inPHPLicenceGNU Lesser General Public License, version 3.0Kindweb framework, software library, free software
TensorFlow Lite LicenceApache Software License 2.0Kindsoftware library, free softwareDeveloperGoogle Brain
Transcode Implemented inCLicenceGNU General Public License, version 2.0Kindmultimedia framework, free software